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authorChristian Wagner <c.wagner@datentechnik-innovation.com>2015-01-29 08:18:00 +0100
committerChristian Wagner <c.wagner@datentechnik-innovation.com>2015-01-29 08:18:00 +0100
commitd45b41a740a6267c78a6ea27b7617c3d317db837 (patch)
tree9f165ae789b1bb8a076dfd1b523240d31d07be5b /id/server/idserverlib/src/main/java/at/gv
parent7ae32988fcf9e4407b4bcae7831772338da55a8f (diff)
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integrate process engine from project 'dti-process-engine' - INCOMPLETE!
- commit neccessary in order to avoid blocking the development process additional small fix due to earlier package renaming
Diffstat (limited to 'id/server/idserverlib/src/main/java/at/gv')
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ExecutionContextImpl.java79
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ExpressionEvaluationContextImpl.java44
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessDefinitionParser.java224
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessDefinitionParserException.java35
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessEngine.java113
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessEngineImpl.java304
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessExecutionException.java36
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessInstance.java166
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessInstanceState.java30
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExecutionContext.java63
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExpressionEvaluationContext.java23
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExpressionEvaluator.java25
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/Task.java21
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/EndEvent.java42
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/ProcessDefinition.java158
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/ProcessNode.java69
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/StartEvent.java45
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/TaskInfo.java94
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/Transition.java136
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/spring/SpringExpressionEvaluator.java61
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/springweb/AbstractAuthSourceServlet.java116
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/springweb/AbstractSpringWebSupportedTask.java73
-rw-r--r--id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/support/SecureRandomHolder.java35
23 files changed, 1992 insertions, 0 deletions
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ExecutionContextImpl.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ExecutionContextImpl.java
new file mode 100644
index 000000000..87ee57a24
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ExecutionContextImpl.java
@@ -0,0 +1,79 @@
+package at.gv.egovernment.moa.id.process;
+
+import java.io.Serializable;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
+import com.datentechnik.process_engine.api.ExecutionContext;
+
+/**
+ * ExecutionContext implementation, related to a certain process instance.
+ *
+ * @author tknall
+ *
+ */
+public class ExecutionContextImpl implements ExecutionContext {
+
+ private static final long serialVersionUID = 1L;
+
+ private Map<String, Serializable> ctxData = Collections.synchronizedMap(new HashMap<String, Serializable>());
+
+ private String processInstanceId;
+
+ /**
+ * Creates a new instance.
+ */
+ public ExecutionContextImpl() {
+ }
+
+ /**
+ * Creates a new instance and associated it with a certain process instance.
+ */
+ public ExecutionContextImpl(String processInstanceId) {
+ this.processInstanceId = processInstanceId;
+ }
+
+ @Override
+ public void setProcessInstanceId(String processInstanceId) {
+ this.processInstanceId = processInstanceId;
+ }
+
+ @Override
+ public String getProcessInstanceId() {
+ return processInstanceId;
+ }
+
+ @Override
+ public Serializable get(String key) {
+ return ctxData.get(key);
+ }
+
+ @Override
+ public Serializable remove(String key) {
+ return ctxData.remove(key);
+ }
+
+ @Override
+ public void put(String key, Serializable object) {
+ ctxData.put(key, object);
+ }
+
+ @Override
+ public Set<String> keySet() {
+ return Collections.unmodifiableSet(ctxData.keySet());
+ }
+
+ @Override
+ public String toString() {
+ StringBuilder builder = new StringBuilder();
+ builder.append("ExecutionContextImpl [");
+ builder.append("id=").append(processInstanceId);
+ builder.append(", variables=");
+ builder.append(ctxData.keySet());
+ builder.append("]");
+ return builder.toString();
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ExpressionEvaluationContextImpl.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ExpressionEvaluationContextImpl.java
new file mode 100644
index 000000000..acc10449f
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ExpressionEvaluationContextImpl.java
@@ -0,0 +1,44 @@
+package at.gv.egovernment.moa.id.process;
+
+import java.io.Serializable;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Set;
+
+import com.datentechnik.process_engine.api.ExecutionContext;
+import com.datentechnik.process_engine.api.ExpressionEvaluationContext;
+
+/**
+ * Context implementation used for expression evaluation only.
+ *
+ * @author tknall
+ *
+ */
+public class ExpressionEvaluationContextImpl implements ExpressionEvaluationContext {
+
+ private static final long serialVersionUID = 1L;
+
+ private Map<String, Serializable> ctxData;
+
+ /**
+ * Creates a new instance and initializes it with data from a given process instance.
+ *
+ * @param processInstance
+ * The process instance.
+ */
+ ExpressionEvaluationContextImpl(ProcessInstance processInstance) {
+ ExecutionContext executionContext = processInstance.getExecutionContext();
+ Set<String> keys = executionContext.keySet();
+ ctxData = Collections.synchronizedMap(new HashMap<String, Serializable>(keys.size()));
+ for (String key : keys) {
+ ctxData.put(key, executionContext.get(key));
+ }
+ }
+
+ @Override
+ public Map<String, Serializable> getCtx() {
+ return Collections.unmodifiableMap(ctxData);
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessDefinitionParser.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessDefinitionParser.java
new file mode 100644
index 000000000..b38bb7aa0
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessDefinitionParser.java
@@ -0,0 +1,224 @@
+package at.gv.egovernment.moa.id.process;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.Iterator;
+import java.util.List;
+import java.util.Objects;
+
+import javax.xml.XMLConstants;
+import javax.xml.namespace.QName;
+import javax.xml.stream.XMLEventReader;
+import javax.xml.stream.XMLInputFactory;
+import javax.xml.stream.XMLStreamConstants;
+import javax.xml.stream.XMLStreamException;
+import javax.xml.stream.events.Attribute;
+import javax.xml.stream.events.StartElement;
+import javax.xml.stream.events.XMLEvent;
+import javax.xml.stream.util.EventReaderDelegate;
+import javax.xml.transform.stax.StAXSource;
+import javax.xml.transform.stream.StreamSource;
+import javax.xml.validation.Schema;
+import javax.xml.validation.SchemaFactory;
+import javax.xml.validation.Validator;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.xml.sax.SAXException;
+
+import com.datentechnik.process_engine.model.EndEvent;
+import com.datentechnik.process_engine.model.ProcessDefinition;
+import com.datentechnik.process_engine.model.ProcessNode;
+import com.datentechnik.process_engine.model.StartEvent;
+import com.datentechnik.process_engine.model.TaskInfo;
+import com.datentechnik.process_engine.model.Transition;
+
+/**
+ * Parses an XML representation of a process definition as defined by the respective XML schema.
+ * <p/
+ * The parser is thread-safe.
+ * @author tknall
+ *
+ */
+public class ProcessDefinitionParser {
+
+ private static final String NS = "http://www.datentechnik.com/process-engine/processdefinition/v1";
+
+ private static Logger log = LoggerFactory.getLogger(ProcessDefinitionParser.class);
+
+ private static class LazyProcessDefinitionSchemaHolder {
+ private static final Schema PD_SCHEMA_INSTANCE;
+ static {
+ try (InputStream in = ProcessDefinitionParser.class.getResourceAsStream("ProcessDefinition.xsd")) {
+ log.trace("Compiling process definition schema.");
+ SchemaFactory factory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI);
+ // schema is thread-safe
+ PD_SCHEMA_INSTANCE = factory.newSchema(new StreamSource(in));
+ } catch (Exception e) {
+ throw new RuntimeException("Unable to compile process definition schema.", e);
+ }
+ }
+ }
+
+ /**
+ * Parses an XML representation of a process definition. The representation is being validated in order to suffice
+ * the related XML schema.
+ *
+ * @param processDefinitionInputStream
+ * The process definition.
+ * @return A new process definition.
+ * @throws ProcessDefinitionParserException
+ * Thrown in case of error parsing the process definition.
+ */
+ public ProcessDefinition parse(InputStream processDefinitionInputStream) throws ProcessDefinitionParserException {
+ XMLEventReader reader = null;
+ final ProcessDefinition pd = new ProcessDefinition();
+ log.debug("Parsing and validating process definition.");
+ try {
+
+ // Standard implementation of XMLInputFactory seems not to be thread-safe
+ XMLInputFactory inputFactory = XMLInputFactory.newInstance();
+ reader = inputFactory.createXMLEventReader(processDefinitionInputStream);
+
+ final List<StartElement> transitionElements = new ArrayList<>();
+ final List<StartEvent> startEvents = new ArrayList<>();
+
+ reader = new EventReaderDelegate(reader) {
+
+ @Override
+ public XMLEvent nextEvent() throws XMLStreamException {
+ XMLEvent event = super.nextEvent();
+
+ switch (event.getEventType()) {
+ case XMLStreamConstants.START_ELEMENT:
+ StartElement element = event.asStartElement();
+ QName qname = element.getName();
+
+ if (NS.equals(qname.getNamespaceURI())) {
+ log.trace("Found process description element '{}'.", qname.getLocalPart());
+ Attribute id = element.getAttributeByName(new QName("id"));
+
+ switch (qname.getLocalPart()) {
+ case "ProcessDefinition":
+ if (id != null) {
+ pd.setId(id.getValue());
+ }
+ break;
+ case "StartEvent":
+ StartEvent startEvent = new StartEvent();
+ if (id != null) {
+ startEvent.setId(id.getValue());
+ }
+ startEvents.add(startEvent);
+ break;
+ case "EndEvent":
+ EndEvent endEvent = new EndEvent();
+ if (id != null) {
+ endEvent.setId(id.getValue());
+ pd.getEndEvents().put(id.getValue(), endEvent);
+ }
+ break;
+ case "Transition":
+ transitionElements.add(element);
+ break;
+ case "Task":
+ TaskInfo taskInfo = new TaskInfo();
+ if (id != null) {
+ taskInfo.setId(id.getValue());
+ pd.getTaskInfos().put(id.getValue(), taskInfo);
+ }
+ Attribute async = element.getAttributeByName(new QName("async"));
+ if (async != null) {
+ taskInfo.setAsync(Boolean.valueOf(async.getValue()));
+ }
+ Attribute implementingClass = element.getAttributeByName(new QName("class"));
+ if (implementingClass != null) {
+ taskInfo.setTaskImplementingClass(implementingClass.getValue());
+ }
+ break;
+ }
+
+ }
+
+ break;
+ }
+
+ return event;
+ }
+
+ };
+
+ // validator is not thread-safe
+ Validator validator = LazyProcessDefinitionSchemaHolder.PD_SCHEMA_INSTANCE.newValidator();
+ validator.validate(new StAXSource(reader));
+ log.trace("Process definition successfully schema validated.");
+
+ // perform some basic checks
+ log.trace("Building model and performing some plausibility checks.");
+ if (startEvents.size() != 1) {
+ throw new ProcessDefinitionParserException("A ProcessDefinition must contain exactly one single StartEvent.");
+ }
+ pd.setStartEvent(startEvents.get(0));
+
+ // link transitions
+ Iterator<StartElement> transitions = transitionElements.iterator();
+ while (transitions.hasNext()) {
+ StartElement element = transitions.next();
+ Transition transition = new Transition();
+ Attribute id = element.getAttributeByName(new QName("id"));
+ if (id != null) {
+ transition.setId(id.getValue());
+ }
+ Attribute conditionExpression = element.getAttributeByName(new QName("conditionExpression"));
+ if (conditionExpression != null) {
+ transition.setConditionExpression(conditionExpression.getValue());
+ }
+ Attribute from = element.getAttributeByName(new QName("from"));
+ if (from != null) {
+ ProcessNode fromNode = pd.getProcessNode(from.getValue());
+ if (fromNode == null) {
+ throw new ProcessDefinitionParserException("Transition's 'from'-attribute refers to a non-existing event or task '" + from.getValue() + '.');
+ }
+ if (fromNode instanceof EndEvent) {
+ throw new ProcessDefinitionParserException("Transition cannot start from end event.");
+ }
+ transition.setFrom(fromNode);
+ fromNode.getOutgoingTransitions().add(transition);
+ }
+ Attribute to = element.getAttributeByName(new QName("to"));
+ if (to != null) {
+ ProcessNode toNode = pd.getProcessNode(to.getValue());
+ if (toNode == null) {
+ throw new ProcessDefinitionParserException("Transition's 'to'-attribute refers to a non-existing event or task '" + to.getValue() + '.');
+ }
+ transition.setTo(toNode);
+ toNode.getIncomingTransitions().add(transition);
+ }
+ if (transition.getConditionExpression() == null && Objects.equals(transition.getFrom(), transition.getTo())) {
+ throw new ProcessDefinitionParserException("Transition's 'from' equals its 'to'. Since no 'conditionExpression' has been set this will cause a loop.");
+ }
+ }
+ log.debug("Process definition '{}' successfully parsed.", pd.getId());
+ return pd;
+
+ } catch (ProcessDefinitionParserException e) {
+ throw e;
+ } catch (XMLStreamException|IOException e) {
+ throw new ProcessDefinitionParserException("Unable to read process definition from inputstream.", e);
+ } catch (SAXException e) {
+ throw new ProcessDefinitionParserException("Schema validation of process description failed.", e);
+ } catch (Exception e) {
+ throw new ProcessDefinitionParserException("Internal error creating process definition from inputstream.", e);
+ } finally {
+ if (reader != null) {
+ try {
+ reader.close();
+ } catch (XMLStreamException e) {
+ // error freeing resources
+ }
+ }
+ }
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessDefinitionParserException.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessDefinitionParserException.java
new file mode 100644
index 000000000..0c214750d
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessDefinitionParserException.java
@@ -0,0 +1,35 @@
+package at.gv.egovernment.moa.id.process;
+
+/**
+ * Exception thrown in case of error parsing a process definition.
+ *
+ * @author tknall
+ *
+ */
+public class ProcessDefinitionParserException extends Exception {
+
+ private static final long serialVersionUID = 1L;
+
+ /**
+ * Creates a new parser exception providing a {@code message} describing the reason and the {@code cause}.
+ *
+ * @param message
+ * The message.
+ * @param cause
+ * The cause.
+ */
+ public ProcessDefinitionParserException(String message, Throwable cause) {
+ super(message, cause);
+ }
+
+ /**
+ * Creates a new parser exception providing a {@code message} describing the reason.
+ *
+ * @param message
+ * The message.
+ */
+ public ProcessDefinitionParserException(String message) {
+ super(message);
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessEngine.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessEngine.java
new file mode 100644
index 000000000..b4135ee41
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessEngine.java
@@ -0,0 +1,113 @@
+package at.gv.egovernment.moa.id.process;
+
+
+import java.io.InputStream;
+import java.io.Serializable;
+
+import com.datentechnik.process_engine.api.ExecutionContext;
+import com.datentechnik.process_engine.model.ProcessDefinition;
+
+/**
+ * Process engine providing means for starting and resuming processes.
+ *
+ * @author tknall
+ */
+public interface ProcessEngine {
+
+ /**
+ * Registers a new process definition. Note that existing definitions with the same identifier will be replaced.
+ *
+ * @param processDefinition
+ * The process definition to be registered.
+ */
+ void registerProcessDefinition(ProcessDefinition processDefinition);
+
+ /**
+ * Registers a new process definition given as {@link InputStream}. Note that existing definitions with the same identifier will be replaced.
+ *
+ * @param processDefinitionInputStream The input stream to the definition to be registered.
+ * @throws ProcessDefinitionParserException Thrown in case of an error parsing the process definition.
+ */
+ void registerProcessDefinition(InputStream processDefinitionInputStream) throws ProcessDefinitionParserException;
+
+ /**
+ * Creates a process instance according to the referenced process definition.
+ * <p/>
+ * Note that the method returns a process instance which will be needed in order to start a process or to continue
+ * process execution after asynchronous task execution (refer to {@link #start(ProcessInstance)} and
+ * {@link #signal(ProcessInstance)} for further information).
+ *
+ * @param processDefinitionId
+ * The identifier of the respective process definition.
+ * @param executionContext The execution context (may be {@code null}).
+ * @return The newly created process instance (never {@code null}).
+ * @throws ProcessExecutionException
+ * Thrown in case of error, e.g. when a {@code processDefinitionId} is referenced that does not exist.
+ */
+ ProcessInstance createProcessInstance(String processDefinitionId, ExecutionContext executionContext) throws ProcessExecutionException;
+
+ /**
+ * Creates a process instance according to the referenced process definition.
+ * <p/>
+ * Note that the method returns a process instance which will be needed in order to start a process or to continue
+ * process execution after asynchronous task execution (refer to {@link #start(ProcessInstance)} and
+ * {@link #signal(ProcessInstance)} for further information).
+ *
+ * @param processDefinitionId
+ * The identifier of the respective process definition.
+ * @return The newly created process instance (never {@code null}).
+ * @throws ProcessExecutionException
+ * Thrown in case of error, e.g. when a {@code processDefinitionId} is referenced that does not exist.
+ */
+ ProcessInstance createProcessInstance(String processDefinitionId) throws ProcessExecutionException;
+
+ /**
+ * Returns the process instance with a given {@code processInstanceId}.
+ *
+ * @param processInstanceId
+ * The process instance id.
+ * @return The process instance (never {@code null}).
+ * @throws IllegalArgumentException
+ * In case the process instance does not/no longer exist.
+ */
+ ProcessInstance getProcessInstance(String processInstanceId);
+
+ /**
+ * Starts the process using the given {@code processInstance}.
+ *
+ * @param processInstance
+ * The process instance.
+ * @throws ProcessExecutionException
+ * Thrown in case of error.
+ */
+ void start(ProcessInstance processInstance) throws ProcessExecutionException;
+
+ /**
+ * Resumes process execution after an asynchronous task has been executed.
+ *
+ * @param processInstance
+ * The process instance.
+ * @throws ProcessExecutionException
+ * Thrown in case of error.
+ */
+ void signal(ProcessInstance processInstance) throws ProcessExecutionException;
+
+ /**
+ * Performs cleanup, removing all process instances that have not been used for a certain time.
+ *
+ * @see #setProcessInstanceMaxIdleTimeSeconds(long)
+ */
+ void cleanup();
+
+ /**
+ * Returns the first process instance with a process context containing some {@code value} stored under key {@code key}.
+ *
+ * @param key
+ * The key.
+ * @param value
+ * The value that needs to match.
+ * @return The process instance or {@code null} in case no process instance was found.
+ */
+ ProcessInstance findProcessInstanceWith(String key, Serializable value);
+
+} \ No newline at end of file
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessEngineImpl.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessEngineImpl.java
new file mode 100644
index 000000000..8f9d73b3d
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessEngineImpl.java
@@ -0,0 +1,304 @@
+package at.gv.egovernment.moa.id.process;
+
+import java.io.InputStream;
+import java.io.Serializable;
+import java.util.Date;
+import java.util.Iterator;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Objects;
+import java.util.concurrent.ConcurrentHashMap;
+
+import org.apache.commons.collections4.CollectionUtils;
+import org.apache.commons.collections4.Predicate;
+import org.apache.commons.lang3.StringUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.slf4j.MDC;
+
+import com.datentechnik.process_engine.api.ExecutionContext;
+import com.datentechnik.process_engine.api.ExpressionEvaluationContext;
+import com.datentechnik.process_engine.api.ExpressionEvaluator;
+import com.datentechnik.process_engine.api.Task;
+import com.datentechnik.process_engine.model.EndEvent;
+import com.datentechnik.process_engine.model.ProcessDefinition;
+import com.datentechnik.process_engine.model.ProcessNode;
+import com.datentechnik.process_engine.model.StartEvent;
+import com.datentechnik.process_engine.model.TaskInfo;
+import com.datentechnik.process_engine.model.Transition;
+
+/**
+ * Process engine implementation allowing starting and continuing processes as well as providing means for cleanup actions.
+ * @author tknall
+ *
+ */
+public class ProcessEngineImpl implements ProcessEngine {
+
+ private Logger log = LoggerFactory.getLogger(getClass());
+
+ private ProcessDefinitionParser pdp = new ProcessDefinitionParser();
+
+ private Map<String, ProcessDefinition> processDefinitions = new ConcurrentHashMap<String, ProcessDefinition>();
+ private Map<String, ProcessInstance> processInstances = new ConcurrentHashMap<String, ProcessInstance>();
+
+ private final static String MDC_CTX_PI_NAME = "processInstanceId";
+ private final static String MDC_CTX_TASK_NAME = "taskId";
+
+ private static final long DEFAULT_PROCESS_INSTANCE_MAX_AGE_SECONDS = 3600;
+ private long processInstanceIdleTimeSeconds = DEFAULT_PROCESS_INSTANCE_MAX_AGE_SECONDS;
+ private ExpressionEvaluator transitionConditionExpressionEvaluator;
+
+ @Override
+ public void registerProcessDefinition(ProcessDefinition processDefinition) {
+ log.info("Registering process definition '{}'.", processDefinition.getId());
+ processDefinitions.put(processDefinition.getId(), processDefinition);
+ }
+
+ @Override
+ public void registerProcessDefinition(InputStream processDefinitionInputStream) throws ProcessDefinitionParserException{
+ registerProcessDefinition(pdp.parse(processDefinitionInputStream));
+ }
+
+ /**
+ * Sets the process definitions.
+ *
+ * @param processDefinitions
+ * The process definitions.
+ * @throws IllegalArgumentException
+ * In case the process definitions contain definitions with the same identifier.
+ */
+ public void setProcessDefinitions(Iterable<ProcessDefinition> processDefinitions) {
+ this.processDefinitions.clear();
+ for (ProcessDefinition pd : processDefinitions) {
+ if (this.processDefinitions.containsKey(pd.getId())) {
+ throw new IllegalArgumentException("Duplicate process definition identifier '" + pd.getId() + "'.");
+ }
+ registerProcessDefinition(pd);
+ }
+ }
+
+ /**
+ * Defines the time frame in seconds an idle process instance will be managed by the process engine. A process
+ * instance with an idle time larger than the given time will be removed.
+ * <p/>
+ * Note that {@link #cleanup()} needs to be called in order to remove expired process instances.
+ *
+ * @param processInstanceMaxIdleTimeSeconds
+ * The maximum idle time in seconds.
+ */
+ public void setProcessInstanceMaxIdleTimeSeconds(long processInstanceMaxIdleTimeSeconds) {
+ this.processInstanceIdleTimeSeconds = processInstanceMaxIdleTimeSeconds;
+ }
+
+ /**
+ * Sets an expression evaluator that should be used to process transition condition expressions.
+ * @param transitionConditionExpressionEvaluator The expression evaluator.
+ */
+ public void setTransitionConditionExpressionEvaluator(
+ ExpressionEvaluator transitionConditionExpressionEvaluator) {
+ this.transitionConditionExpressionEvaluator = transitionConditionExpressionEvaluator;
+ }
+
+
+ @Override
+ public ProcessInstance createProcessInstance(String processDefinitionId, ExecutionContext executionContext) throws ProcessExecutionException {
+ // look for respective process definition
+ ProcessDefinition pd = processDefinitions.get(processDefinitionId);
+ if (pd == null) {
+ throw new ProcessExecutionException("Unable to find process definition for process '" + processDefinitionId + "'.");
+ }
+ // create and keep process instance
+ ProcessInstance pi = new ProcessInstance(pd, executionContext);
+ log.info("Creating process instance from process definition '{}': {}", processDefinitionId, pi.getId());
+ processInstances.put(pi.getId(), pi);
+ return pi;
+ }
+
+ @Override
+ public ProcessInstance createProcessInstance(String processDefinitionId) throws ProcessExecutionException {
+ return createProcessInstance(processDefinitionId, null);
+ }
+
+ @Override
+ public void start(ProcessInstance pi) throws ProcessExecutionException {
+ MDC.put(MDC_CTX_PI_NAME, pi.getId());
+ try {
+ if (!ProcessInstanceState.NOT_STARTED.equals(pi.getState())) {
+ throw new ProcessExecutionException("Process instance '" + pi.getId() + "' has already been started (current state is " + pi.getState() + ").");
+ }
+ log.info("Starting process instance '{}'.", pi.getId());
+ // execute process
+ pi.setState(ProcessInstanceState.STARTED);
+ execute(pi);
+ } finally {
+ MDC.remove(MDC_CTX_PI_NAME);
+ }
+ }
+
+ @Override
+ public void signal(ProcessInstance pi) throws ProcessExecutionException {
+ MDC.put(MDC_CTX_PI_NAME, pi.getId());
+ try {
+ if (!ProcessInstanceState.SUSPENDED.equals(pi.getState())) {
+ throw new ProcessExecutionException("Process instance '" + pi.getId() + "' has not been suspended (current state is " + pi.getState() + ").");
+ }
+ log.info("Waking up process instance '{}'.", pi.getId());
+ pi.setState(ProcessInstanceState.STARTED);
+ execute(pi);
+ } finally {
+ MDC.remove(MDC_CTX_PI_NAME);
+ }
+ }
+
+ @Override
+ public synchronized void cleanup() {
+ log.trace("Cleanup job started.");
+ Iterator<Entry<String, ProcessInstance>> it = processInstances.entrySet().iterator();
+ while (it.hasNext()) {
+ Entry<String, ProcessInstance> entry = it.next();
+ ProcessInstance pi = entry.getValue();
+ log.trace("Checking process instance {}.", pi);
+ long ageMillis = new Date().getTime() - pi.getLru().getTime();
+ if (ageMillis > processInstanceIdleTimeSeconds * 1000) {
+ log.info("Removing process instance '{}'.", pi.getId());
+ processInstances.remove(entry.getKey());
+ }
+ }
+ log.trace("Cleanup job completed.");
+ }
+
+ /**
+ * Instantates a task implementation given by a {@link TaskInfo}.
+ * @param ti The task info.
+ * @return A Task implementation or {@code null} if the task info does not reference any task implementing classes.
+ * @throws ProcessExecutionException Thrown in case of error (when the referenced class does not implement {@link Task} for instance).
+ */
+ private Task createTaskInstance(TaskInfo ti) throws ProcessExecutionException {
+ String clazz = StringUtils.trimToNull(ti.getTaskImplementingClass());
+ Task task = null;
+
+ if (clazz != null) {
+ log.debug("Instantiating task implementing class '{}'.", clazz);
+ Class<?> instanceClass = null;
+ try {
+ instanceClass = Class.forName(clazz, true, Thread.currentThread().getContextClassLoader());
+ } catch (Exception e) {
+ throw new ProcessExecutionException("Unable to get class '" + clazz + "' associated with task '" + ti.getId() + "' .", e);
+ }
+ if (!Task.class.isAssignableFrom(instanceClass)) {
+ throw new ProcessExecutionException("Class '" + clazz + "' associated with task '" + ti.getId() + "' is not assignable to " + Task.class.getName() + ".");
+ }
+ try {
+ task = (Task) instanceClass.newInstance();
+ } catch (Exception e) {
+ throw new ProcessExecutionException("Unable to instantiate class '" + clazz + "' associated with task '" + ti.getId() + "' .", e);
+ }
+ }
+
+ return task;
+ }
+
+ /**
+ * Starts/executes a given process instance.
+ * @param pi The process instance.
+ * @throws ProcessExecutionException Thrown in case of error.
+ */
+ private void execute(final ProcessInstance pi) throws ProcessExecutionException {
+ if (ProcessInstanceState.ENDED.equals(pi.getState())) {
+ throw new ProcessExecutionException("Process for instance '" + pi.getId() + "' has already been ended.");
+ }
+ ProcessDefinition pd = pi.getProcessDefinition();
+ ProcessNode processNode = pd.getProcessNode(pi.getNextId());
+ log.debug("Processing node '{}'.", processNode.getId());
+
+ // distinguish process node types StartEvent, TaskInfo and EndEvent
+
+ if (processNode instanceof TaskInfo) {
+ // TaskInfo types need to be executed
+ TaskInfo ti = (TaskInfo) processNode;
+ MDC.put(MDC_CTX_TASK_NAME, ti.getId());
+ try {
+ log.info("Processing task '{}'.", ti.getId());
+ Task task = createTaskInstance(ti);
+ if (task != null) {
+ try {
+ log.info("Executing task implementation for task '{}'.", ti.getId());
+ log.debug("Execution context before task execution: {}", pi.getExecutionContext().keySet());
+ task.execute(pi.getExecutionContext());
+ log.info("Returned from execution of task '{}'.", ti.getId());
+ log.debug("Execution context after task execution: {}", pi.getExecutionContext().keySet());
+ } catch (Throwable t) {
+ throw new ProcessExecutionException("Error executing task '" + ti.getId() + "'.", t);
+ }
+ } else {
+ log.debug("No task implementing class set.");
+ }
+ } finally {
+ MDC.remove(MDC_CTX_TASK_NAME);
+ }
+
+ } else if (processNode instanceof EndEvent) {
+ log.info("Finishing process instance '{}'.", pi.getId());
+ processInstances.remove(pi.getId());
+ pi.setState(ProcessInstanceState.ENDED);
+ log.debug("Final process context: {}", pi.getExecutionContext().keySet());
+ return;
+ }
+
+ final ExpressionEvaluationContext expressionContext = new ExpressionEvaluationContextImpl(pi);
+
+ // traverse pointer
+ Transition t = CollectionUtils.find(processNode.getOutgoingTransitions(), new Predicate<Transition>() {
+ @Override
+ public boolean evaluate(Transition transition) {
+ if (transitionConditionExpressionEvaluator != null && transition.getConditionExpression() != null) {
+ log.trace("Evaluating transition expression '{}'.", transition.getConditionExpression());
+ return transitionConditionExpressionEvaluator.evaluate(expressionContext, transition.getConditionExpression());
+ }
+ return true;
+ }
+ });
+ if (t == null) {
+ throw new ProcessExecutionException("No valid transition starting from process node '" + processNode.getId()+ "'.");
+ }
+ log.trace("Found suitable transition: {}", t);
+ // update pointer
+ log.trace("Shifting process token from '{}' to '{}'.", pi.getNextId(), t.getTo().getId());
+ pi.setNextId(t.getTo().getId());
+
+ // inspect current task
+ if (t.getTo() instanceof TaskInfo && (((TaskInfo) t.getTo()).isAsync())) {
+ // immediately return in case of asynchonous task
+ log.info("Suspending process instance '{}' for asynchronous task '{}'.", pi.getId(), t.getTo().getId());
+ pi.setState(ProcessInstanceState.SUSPENDED);
+ return;
+ }
+
+ // continue execution in case of StartEvent or Task
+ if (processNode instanceof StartEvent || processNode instanceof TaskInfo) {
+ execute(pi);
+ }
+ }
+
+ @Override
+ public ProcessInstance getProcessInstance(String processInstanceId) {
+ ProcessInstance processInstance = processInstances.get(processInstanceId);
+ if (processInstance == null) {
+ throw new IllegalArgumentException("The process instance '" + processInstanceId + "' does not/no longer exist.");
+ }
+ return processInstance;
+ }
+
+ @Override
+ public ProcessInstance findProcessInstanceWith(String key, Serializable value) {
+ Iterator<ProcessInstance> it = processInstances.values().iterator();
+ while (it.hasNext()) {
+ ProcessInstance pi = it.next();
+ if (Objects.equals(pi.getExecutionContext().get(key), value)) {
+ return pi;
+ }
+ }
+ return null;
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessExecutionException.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessExecutionException.java
new file mode 100644
index 000000000..821bbe6dc
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessExecutionException.java
@@ -0,0 +1,36 @@
+package at.gv.egovernment.moa.id.process;
+
+/**
+ * Indicates a problem when executing a process.
+ *
+ * @author tknall
+ *
+ */
+public class ProcessExecutionException extends Exception {
+
+ private static final long serialVersionUID = 1L;
+
+ /**
+ * Creates a new process execution exception providing a {@code message} describing the reason and the respective
+ * {@code cause}.
+ *
+ * @param message
+ * The message.
+ * @param cause
+ * The cause.
+ */
+ public ProcessExecutionException(String message, Throwable cause) {
+ super(message, cause);
+ }
+
+ /**
+ * Creates a new process execution exception providing a {@code message} describing the reason.
+ *
+ * @param message
+ * The message.
+ */
+ public ProcessExecutionException(String message) {
+ super(message);
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessInstance.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessInstance.java
new file mode 100644
index 000000000..0899426ca
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessInstance.java
@@ -0,0 +1,166 @@
+package at.gv.egovernment.moa.id.process;
+
+import java.io.Serializable;
+import java.util.Date;
+
+import org.apache.commons.lang3.RandomStringUtils;
+import org.apache.commons.lang3.time.DurationFormatUtils;
+
+import com.datentechnik.process_engine.api.ExecutionContext;
+import com.datentechnik.process_engine.model.ProcessDefinition;
+import com.datentechnik.process_engine.support.SecureRandomHolder;
+
+/**
+ * Represents a process being executed. The process instance provides information about the process and its state.
+ *
+ * @author tknall
+ *
+ */
+public class ProcessInstance implements Serializable {
+
+ private static final long serialVersionUID = 1L;
+ private static final int RND_ID_LENGTH = 22;
+
+ private ProcessDefinition processDefinition;
+ private String nextId;
+ private Date lru;
+ private ExecutionContext executionContext;
+ private ProcessInstanceState state = ProcessInstanceState.NOT_STARTED;
+
+ /**
+ * Creates a new process instance, based on a given process definition.<p/>
+ * An execution context will be created internally.
+ *
+ * @param processDefinition
+ * The process definition.
+ */
+ ProcessInstance(ProcessDefinition processDefinition) {
+ this(processDefinition, null);
+ }
+
+ /**
+ * Creates a new process instance, based on a given process definition and a
+ * given execution context. If the given execution context is {@code null} a new execution context will be created.<p/>
+ * The process instance id of the execution context will automatically be set (and overwritten if already set).
+ *
+ * @param processDefinition
+ * The process definition.
+ * @param executionContext
+ * The execution context (may be {@code null}). If {@code null} a new execution context will be created internally.
+ */
+ ProcessInstance(ProcessDefinition processDefinition, ExecutionContext executionContext) {
+ this.processDefinition = processDefinition;
+ nextId = processDefinition.getStartEvent().getId();
+ String pdIdLocalPart = RandomStringUtils.random(RND_ID_LENGTH, 0, 0, true, true, null,
+ SecureRandomHolder.getInstance());
+ if (executionContext == null) {
+ executionContext = new ExecutionContextImpl();
+ }
+ executionContext.setProcessInstanceId(this.processDefinition.getId() + "-" + pdIdLocalPart);
+ this.executionContext = executionContext;
+ touch();
+ }
+
+ /**
+ * Returns the underlying process definition.
+ *
+ * @return The underlying process definition.
+ */
+ ProcessDefinition getProcessDefinition() {
+ touch();
+ return processDefinition;
+ }
+
+ /**
+ * Returns the id of the process node to be executed next.
+ *
+ * @return The process node pointer indicating the process node to be executed next.
+ */
+ public String getNextId() {
+ touch();
+ return nextId;
+ }
+
+ /**
+ * Sets the internal pointer to the process node to be executed next.
+ *
+ * @param nextId
+ * The process node id to be executed next.
+ */
+ void setNextId(String nextId) {
+ touch();
+ this.nextId = nextId;
+ }
+
+ /**
+ * Returns the current state of the process instance.
+ *
+ * @return The current state.
+ */
+ public ProcessInstanceState getState() {
+ touch();
+ return state;
+ }
+
+ /**
+ * Sets the current state of the process instance.
+ *
+ * @param state
+ * The current state.
+ */
+ void setState(ProcessInstanceState state) {
+ touch();
+ this.state = state;
+ }
+
+ public String getId() {
+ touch();
+ return executionContext.getProcessInstanceId();
+ }
+
+ /**
+ * Updates the last recently used date of the process instance.
+ */
+ private void touch() {
+ lru = new Date();
+ }
+
+ /**
+ * Returns the date the process instance has been accessed last.
+ *
+ * @return The last recently used date.
+ */
+ Date getLru() {
+ return lru;
+ }
+
+ /**
+ * Returns the associated execution context.
+ * @return The execution context (never {@code null}).
+ */
+ public ExecutionContext getExecutionContext() {
+ touch();
+ return executionContext;
+ }
+
+ @Override
+ public String toString() {
+ StringBuilder builder = new StringBuilder();
+ builder.append("ProcessInstance [");
+ builder.append("id=").append(executionContext.getProcessInstanceId());
+ builder.append(", idle since=").append(
+ DurationFormatUtils.formatDurationWords(new Date().getTime() - this.lru.getTime(), true, true));
+ if (processDefinition != null) {
+ builder.append(", processDefinition.id=");
+ builder.append(processDefinition.getId());
+ }
+ if (nextId != null) {
+ builder.append(", nextId=");
+ builder.append(nextId);
+ }
+ builder.append(", executionContext=").append(executionContext);
+ builder.append("]");
+ return builder.toString();
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessInstanceState.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessInstanceState.java
new file mode 100644
index 000000000..2765283a0
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/ProcessInstanceState.java
@@ -0,0 +1,30 @@
+package at.gv.egovernment.moa.id.process;
+
+/**
+ * Represents a certain process instance state.
+ * @author tknall
+ *
+ */
+public enum ProcessInstanceState {
+
+ /**
+ * Indicates that the process with this process instance has not yet been started.
+ */
+ NOT_STARTED,
+
+ /**
+ * Indicates that the process is currently running.
+ */
+ STARTED,
+
+ /**
+ * Indicates that the process has been suspended until being waken up by someonce calling {@code signal}.
+ */
+ SUSPENDED,
+
+ /**
+ * Indicates that the process has been completed.
+ */
+ ENDED
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExecutionContext.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExecutionContext.java
new file mode 100644
index 000000000..4a9dfc336
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExecutionContext.java
@@ -0,0 +1,63 @@
+package at.gv.egovernment.moa.id.process.api;
+
+import java.io.Serializable;
+import java.util.Set;
+
+/**
+ * Encapsulates data needed for or provided by task execution.
+ *
+ * @author tknall
+ *
+ */
+public interface ExecutionContext extends Serializable {
+
+ /**
+ * Returns the identifier of underlying process instance.
+ *
+ * @return The identifier of the process instance.
+ */
+ String getProcessInstanceId();
+
+ /**
+ * Sets the identifier of underlying process instance.
+ *
+ * @param processInstanceId
+ * The identifier of the process instance.
+ */
+ void setProcessInstanceId(String processInstanceId);
+
+ /**
+ * Stores a serializable object using {@code key}.
+ *
+ * @param key
+ * The key under that the {@code object} should be stored.
+ * @param object The object to be stored.
+ */
+ void put(String key, Serializable object);
+
+ /**
+ * Returns an serializable object stored within this process context using {@code key}.
+ *
+ * @param key
+ * The key that has been used to store the serializable object (may be {@code null}).
+ * @return The object or {@code null} in case the key does not relate to a stored object or the stored object itself
+ * was {@code null}.
+ */
+ Serializable get(String key);
+
+ /**
+ * Removes the object stored using {@code key}.
+ * @param key
+ * The key that has been used to store the serializable object (may be {@code null}).
+ * @return The object that has been removed or {@code null} there was no object stored using {@code key}.
+ */
+ Serializable remove(String key);
+
+ /**
+ * Returns an unmodifiable set containing the stored keys.
+ *
+ * @return The keyset (never {@code null}).
+ */
+ Set<String> keySet();
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExpressionEvaluationContext.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExpressionEvaluationContext.java
new file mode 100644
index 000000000..bb3b267cf
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExpressionEvaluationContext.java
@@ -0,0 +1,23 @@
+package at.gv.egovernment.moa.id.process.api;
+
+import java.io.Serializable;
+import java.util.Map;
+
+import com.datentechnik.process_engine.model.Transition;
+
+/**
+ * Context used for evaluation of condition expressions set for {@linkplain Transition Transitions}.
+ *
+ * @author tknall
+ *
+ */
+public interface ExpressionEvaluationContext extends Serializable {
+
+ /**
+ * Returns the context data map used for expression evaluation.
+ *
+ * @return An unmodifiable map (never {@code null}).
+ */
+ Map<String, Serializable> getCtx();
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExpressionEvaluator.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExpressionEvaluator.java
new file mode 100644
index 000000000..fe0743201
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/ExpressionEvaluator.java
@@ -0,0 +1,25 @@
+package at.gv.egovernment.moa.id.process.api;
+
+/**
+ * Evaluates a given {@code expression} returning a boolean value.
+ *
+ * @author tknall
+ */
+public interface ExpressionEvaluator {
+
+ /**
+ * Evaluates a given {@code expression} returning a boolean value.
+ *
+ * @param expressionContext
+ * The context which can be used for evaluation of the expression.
+ * @param expression
+ * The expression resulting in a boolean (must not be {@code null}).
+ * @return A boolean value.
+ * @throws IllegalArgumentException
+ * In case of an invalid {@code expression}.
+ * @throws NullPointerException
+ * In case of a {@code null} expression.
+ */
+ boolean evaluate(ExpressionEvaluationContext expressionContext, String expression);
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/Task.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/Task.java
new file mode 100644
index 000000000..6401b1d5d
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/api/Task.java
@@ -0,0 +1,21 @@
+package at.gv.egovernment.moa.id.process.api;
+
+
+/**
+ * Represents a single task to be performed upon process execution.
+ *
+ * @author tknall
+ *
+ */
+public interface Task {
+
+ /**
+ * Executes this task.
+ *
+ * @param executionContext
+ * Provides execution related information.
+ * @throws Exception An exception upon task execution.
+ */
+ void execute(ExecutionContext executionContext) throws Exception;
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/EndEvent.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/EndEvent.java
new file mode 100644
index 000000000..49fb082ea
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/EndEvent.java
@@ -0,0 +1,42 @@
+package at.gv.egovernment.moa.id.process.model;
+
+import java.io.Serializable;
+
+import org.apache.commons.collections4.CollectionUtils;
+
+/**
+ * Represents an end event. Process execution terminates when an end event is reached.
+ *
+ * @author tknall
+ */
+public class EndEvent extends ProcessNode implements Serializable {
+
+ private static final long serialVersionUID = 1L;
+
+ @Override
+ public String toString() {
+ StringBuilder builder = new StringBuilder();
+ builder.append("EndEvent [");
+ if (getId() != null) {
+ builder.append("id=");
+ builder.append(getId());
+ }
+ if (CollectionUtils.isNotEmpty(getIncomingTransitions())) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("incomingTransitions=");
+ builder.append(getIncomingTransitions());
+ }
+ if (CollectionUtils.isNotEmpty(getOutgoingTransitions())) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("outgoingTransitions=");
+ builder.append(getOutgoingTransitions());
+ }
+ builder.append("]");
+ return builder.toString();
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/ProcessDefinition.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/ProcessDefinition.java
new file mode 100644
index 000000000..19e78b0e6
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/ProcessDefinition.java
@@ -0,0 +1,158 @@
+package at.gv.egovernment.moa.id.process.model;
+
+import java.util.LinkedHashMap;
+import java.util.Map;
+import java.util.Objects;
+
+import com.datentechnik.process_engine.ProcessDefinitionParser;
+
+/**
+ * Represents a single process definition containing
+ * <ul>
+ * <li>a {@link StartEvent},</li>
+ * <li>one or more {@linkplain TaskInfo Tasks},</li>
+ * <li>one or more {@linkplain EndEvent EndEvents} and</li>
+ * <li>some {@linkplain Transition Transitions} linking StartEvents, Tasks and EndEvents.
+ * </ul>
+ *
+ * @author tknall
+ *
+ */
+public class ProcessDefinition {
+
+ private String id;
+ private StartEvent startEvent;
+ private Map<String, TaskInfo> taskInfos = new LinkedHashMap<>();
+ private Map<String, EndEvent> endEvents = new LinkedHashMap<>();
+
+ /**
+ * Returns the unique identifier of the process definition.
+ *
+ * @return The unique identifier (never {@code null} if process definition comes from
+ * {@link ProcessDefinitionParser}).
+ */
+ public String getId() {
+ return id;
+ }
+
+ /**
+ * Sets the unique identifier of the process definition.
+ *
+ * @param id
+ * The unique identifier.
+ */
+ public void setId(String id) {
+ this.id = id;
+ }
+
+ /**
+ * Returns the start event of the process definition.
+ *
+ * @return The start event (never {@code null} if process definition comes from {@link ProcessDefinitionParser}).
+ */
+ public StartEvent getStartEvent() {
+ return startEvent;
+ }
+
+ /**
+ * Sets the start event of the process definition.
+ *
+ * @param startEvent
+ * The start event.
+ */
+ public void setStartEvent(StartEvent startEvent) {
+ this.startEvent = startEvent;
+ }
+
+ /**
+ * Returns a map containing the tasks of the process definition.
+ *
+ * @return The tasks (map is never {@code null} if process definition comes from {@link ProcessDefinitionParser}).
+ */
+ public Map<String, TaskInfo> getTaskInfos() {
+ return taskInfos;
+ }
+
+ /**
+ * Sets the map containing the tasks.
+ *
+ * @param taskInfos
+ * The map containing the tasks.
+ */
+ public void setTaskInfos(Map<String, TaskInfo> taskInfos) {
+ this.taskInfos = taskInfos;
+ }
+
+ /**
+ * Returns a map containing the end events of the process description.
+ *
+ * @return The map containing the end events (map is never {@code null} if process definition comes from
+ * {@link ProcessDefinitionParser}).
+ */
+ public Map<String, EndEvent> getEndEvents() {
+ return endEvents;
+ }
+
+ /**
+ * Sets a map containing the end events of the process description.
+ *
+ * @param endEvents
+ * The map containing the end events.
+ */
+ public void setEndEvents(Map<String, EndEvent> endEvents) {
+ this.endEvents = endEvents;
+ }
+
+ /**
+ * Returns the process node associated with the given {@code id}.
+ *
+ * @param id
+ * The identifier of the process node.
+ * @return The process node (may be {code null} when no process node with the given {@code id} exists).
+ */
+ public ProcessNode getProcessNode(String id) {
+ Objects.requireNonNull(id, "Identifier must not be null.");
+ if (startEvent != null && id.equals(startEvent.getId())) {
+ return startEvent;
+ }
+ TaskInfo task = taskInfos.get(id);
+ if (task != null) {
+ return task;
+ }
+ return endEvents.get(id);
+ }
+
+ @Override
+ public String toString() {
+ StringBuilder builder = new StringBuilder();
+ if (id != null) {
+ builder.append("id=");
+ builder.append(id);
+ }
+ if (startEvent != null) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("startEvent=");
+ builder.append(startEvent);
+ }
+ if (taskInfos != null && !taskInfos.isEmpty()) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("tasksInfos=");
+ builder.append(taskInfos.values());
+ }
+ if (endEvents != null && !endEvents.isEmpty()) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("endEvents=");
+ builder.append(endEvents.values());
+ }
+ builder.insert(0, "ProcessDefinition [");
+ builder.append("]");
+ return builder.toString();
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/ProcessNode.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/ProcessNode.java
new file mode 100644
index 000000000..a94d33943
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/ProcessNode.java
@@ -0,0 +1,69 @@
+package at.gv.egovernment.moa.id.process.model;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import com.datentechnik.process_engine.ProcessDefinitionParser;
+
+/**
+ * Represents a {@link StartEvent}, an {@link EndEvent} or a {@linkplain TaskInfo Task}.
+ * @author tknall
+ *
+ */
+public abstract class ProcessNode {
+
+ private String id;
+ private List<Transition> outgoingTransitions = new ArrayList<>();
+ private List<Transition> incomingTransitions = new ArrayList<>();
+
+ /**
+ * Returns the unique identifier of the process node.
+ *
+ * @return The unique identifier (never {@code null} if process node comes from a process definition from
+ * {@link ProcessDefinitionParser}).
+ */
+ public String getId() {
+ return id;
+ }
+
+ /**
+ * Sets the unique identifier of the process node.
+ * @param id The unique identifier.
+ */
+ public void setId(String id) {
+ this.id = id;
+ }
+
+ /**
+ * Returns a list of transitions pointing from this process node to another one.
+ * @return A list of transitions (never {@code null} if process node comes from a process definition from {@link ProcessDefinitionParser}).
+ */
+ public List<Transition> getOutgoingTransitions() {
+ return outgoingTransitions;
+ }
+
+ /**
+ * Sets the list of transitions pointing from this process node to another one.
+ * @param outgoingTransitions The list of transitions originating from this process node.
+ */
+ public void setOutgoingTransitions(List<Transition> outgoingTransitions) {
+ this.outgoingTransitions = outgoingTransitions;
+ }
+
+ /**
+ * Returns a list of transitions pointing from another process node to this one.
+ * @return A list of transitions (never {@code null} if process node comes from a process definition from {@link ProcessDefinitionParser}).
+ */
+ public List<Transition> getIncomingTransitions() {
+ return incomingTransitions;
+ }
+
+ /**
+ * Sets the list of transitions pointing from another process node to this one.
+ * @param incomingTransitions A list of transitions pointing to this process node.
+ */
+ public void setIncomingTransitions(List<Transition> incomingTransitions) {
+ this.incomingTransitions = incomingTransitions;
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/StartEvent.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/StartEvent.java
new file mode 100644
index 000000000..60175e09c
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/StartEvent.java
@@ -0,0 +1,45 @@
+package at.gv.egovernment.moa.id.process.model;
+
+import java.io.Serializable;
+
+import org.apache.commons.collections4.CollectionUtils;
+
+/**
+ * Represents a start event. Each process description contains a single start event. Process execution starts with a
+ * start event.
+ *
+ * @author tknall
+ *
+ */
+public class StartEvent extends ProcessNode implements Serializable {
+
+ private static final long serialVersionUID = 1L;
+
+ @Override
+ public String toString() {
+ StringBuilder builder = new StringBuilder();
+ builder.append("StartEvent [");
+ if (getId() != null) {
+ builder.append("id=");
+ builder.append(getId());
+ }
+ if (CollectionUtils.isNotEmpty(getIncomingTransitions())) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("incomingTransitions=");
+ builder.append(getIncomingTransitions());
+ }
+ if (CollectionUtils.isNotEmpty(getOutgoingTransitions())) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("outgoingTransitions=");
+
+ builder.append(getOutgoingTransitions());
+ }
+ builder.append("]");
+ return builder.toString();
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/TaskInfo.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/TaskInfo.java
new file mode 100644
index 000000000..b7f13a880
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/TaskInfo.java
@@ -0,0 +1,94 @@
+package at.gv.egovernment.moa.id.process.model;
+
+import java.io.Serializable;
+
+import org.apache.commons.collections4.CollectionUtils;
+
+import com.datentechnik.process_engine.api.Task;
+
+/**
+ * Represents information about a single task to be performed upon process execution.
+ * @author tknall
+ *
+ */
+public class TaskInfo extends ProcessNode implements Serializable {
+
+ private static final long serialVersionUID = 1L;
+ private static final boolean DEFAULT_ASYNC = false;
+
+ private String taskImplementingClass;
+ private boolean async = DEFAULT_ASYNC;
+
+ /**
+ * Determines if the task is marked asynchronous ({@code true}) or synchronous ({@code false}).
+ * @return A flag indicating if the task should be executed asynchronously or synchronously. (Default: {@code false})
+ */
+ public boolean isAsync() {
+ return async;
+ }
+
+ /**
+ * Marks a task to executed asynchronously ({@code true}) or synchronously ({@code false}).
+ * @param async The flag.
+ */
+ public void setAsync(boolean async) {
+ this.async = async;
+ }
+
+ /**
+ * Returns the class that implements the actual task (must implement {@link Task}).
+ * @return The task implementing class.
+ */
+ public String getTaskImplementingClass() {
+ return taskImplementingClass;
+ }
+
+ /**
+ * Sets the class that implements the actual task (must implement {@link Task}).
+ * @param taskImplementingClass The task implementing class.
+ */
+ public void setTaskImplementingClass(String taskImplementingClass) {
+ this.taskImplementingClass = taskImplementingClass;
+ }
+
+ @Override
+ public String toString() {
+ StringBuilder builder = new StringBuilder();
+ if (getId() != null) {
+ builder.append("id=");
+ builder.append(getId());
+ }
+ if (async != DEFAULT_ASYNC) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("async=");
+ builder.append(async);
+ }
+ if (taskImplementingClass != null) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("taskImplementingClass=");
+ builder.append(taskImplementingClass);
+ }
+ if (CollectionUtils.isNotEmpty(getIncomingTransitions())) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("incomingTransitions=");
+ builder.append(getIncomingTransitions());
+ }
+ if (CollectionUtils.isNotEmpty(getOutgoingTransitions())) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("outgoingTransitions=");
+ builder.append(getOutgoingTransitions());
+ }
+ builder.insert(0, "TaskInfo [");
+ builder.append("]");
+ return builder.toString();
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/Transition.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/Transition.java
new file mode 100644
index 000000000..9d9c44c8c
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/model/Transition.java
@@ -0,0 +1,136 @@
+package at.gv.egovernment.moa.id.process.model;
+
+import java.io.Serializable;
+
+import com.datentechnik.process_engine.ProcessDefinitionParser;
+
+/**
+ * Represents a single transition from a {@link StartEvent} or {@linkplain TaskInfo Task} to another
+ * {@linkplain TaskInfo Task} or {@link EndEvent}.
+ *
+ * @author tknall
+ *
+ */
+public class Transition implements Serializable {
+
+ private static final long serialVersionUID = 1L;
+
+ private String id;
+ private String conditionExpression;
+ private ProcessNode from;
+ private ProcessNode to;
+
+ /**
+ * Returns the process node (effectively a {@link StartEvent} or {@linkplain TaskInfo Task}) the transition is
+ * pointing from.
+ *
+ * @return The transition's source process node (never {@code null} if transition comes from a process definition
+ * from {@link ProcessDefinitionParser}).
+ */
+ public ProcessNode getFrom() {
+ return from;
+ }
+
+ /**
+ * Sets the process node the transition is pointing from.
+ *
+ * @param from
+ * The transition's source process node.
+ */
+ public void setFrom(ProcessNode from) {
+ this.from = from;
+ }
+
+ /**
+ * Returns the process node (effectively a {@linkplain TaskInfo Task} or {@link EndEvent}) the transition is
+ * pointing to.
+ *
+ * @return The transition's destination process node (never {@code null} if transition comes from a process
+ * definition from {@link ProcessDefinitionParser}).
+ */
+ public ProcessNode getTo() {
+ return to;
+ }
+
+ /**
+ * Sets the process node the transition is pointing to.
+ *
+ * @param to
+ * The transition's destination process node.
+ */
+ public void setTo(ProcessNode to) {
+ this.to = to;
+ }
+
+ /**
+ * Returns the unique identifier of the transition.
+ *
+ * @return The unique identifier (may be {@code null}).
+ */
+ public String getId() {
+ return id;
+ }
+
+ /**
+ * Sets the unique identifier of the transition.
+ *
+ * @param id
+ * The unique identifier.
+ */
+ public void setId(String id) {
+ this.id = id;
+ }
+
+ /**
+ * Returns the condition expression for this transition.
+ *
+ * @return The condition expression (may be {@code null}).
+ */
+ public String getConditionExpression() {
+ return conditionExpression;
+ }
+
+ /**
+ * Sets the condition expression for this transition.
+ *
+ * @param conditionExpression
+ * The condition expression.
+ */
+ public void setConditionExpression(String conditionExpression) {
+ this.conditionExpression = conditionExpression;
+ }
+
+ @Override
+ public String toString() {
+ StringBuilder builder = new StringBuilder();
+ if (id != null) {
+ builder.append("id=");
+ builder.append(id);
+ }
+ if (from != null) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("from.id=");
+ builder.append(from.getId());
+ }
+ if (to != null) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("to.id=");
+ builder.append(to.getId());
+ }
+ if (conditionExpression != null) {
+ if (builder.length() > 0) {
+ builder.append(", ");
+ }
+ builder.append("conditionExpression=");
+ builder.append(conditionExpression);
+ }
+ builder.insert(0, "Transition [");
+ builder.append("]");
+ return builder.toString();
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/spring/SpringExpressionEvaluator.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/spring/SpringExpressionEvaluator.java
new file mode 100644
index 000000000..1c91cf780
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/spring/SpringExpressionEvaluator.java
@@ -0,0 +1,61 @@
+package at.gv.egovernment.moa.id.process.spring;
+
+import java.util.Objects;
+
+import javax.annotation.PostConstruct;
+
+import org.apache.commons.lang3.BooleanUtils;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.expression.BeanFactoryResolver;
+import org.springframework.expression.Expression;
+import org.springframework.expression.ExpressionParser;
+import org.springframework.expression.spel.standard.SpelExpressionParser;
+import org.springframework.expression.spel.support.StandardEvaluationContext;
+
+import com.datentechnik.process_engine.api.ExpressionEvaluationContext;
+import com.datentechnik.process_engine.api.ExpressionEvaluator;
+import com.datentechnik.process_engine.model.Transition;
+
+/**
+ * Expression evaluator for processing {@link Transition} conditions allowing to reference Spring beans from the
+ * application context.
+ *
+ * @author tknall
+ *
+ */
+public class SpringExpressionEvaluator implements ExpressionEvaluator {
+
+ private Logger log = LoggerFactory.getLogger(getClass());
+ private ExpressionParser parser = new SpelExpressionParser();
+ private StandardEvaluationContext evaluationContext = new StandardEvaluationContext();
+
+ @Autowired(required = false)
+ private ApplicationContext ctx;
+
+ @PostConstruct
+ private void init() {
+ if (ctx != null) {
+ evaluationContext.setBeanResolver(new BeanFactoryResolver(ctx));
+ }
+ }
+
+ @Override
+ public boolean evaluate(ExpressionEvaluationContext expressionContext, String expression) {
+ Objects.requireNonNull(expression, "Expression must not be null.");
+ log.trace("Evaluating '{}'.", expression);
+
+ Expression expr = parser.parseExpression(expression);
+ Boolean result = expr.getValue(evaluationContext, expressionContext, Boolean.class);
+ if (result == null) {
+ log.warn("Evaluation of '{}' results in null-value.", expression);
+ } else {
+ log.debug("Expression '{}' -> {}", expression, result);
+ }
+
+ return BooleanUtils.isTrue(result);
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/springweb/AbstractAuthSourceServlet.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/springweb/AbstractAuthSourceServlet.java
new file mode 100644
index 000000000..4b5af854e
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/springweb/AbstractAuthSourceServlet.java
@@ -0,0 +1,116 @@
+package at.gv.egovernment.moa.id.process.springweb;
+
+import javax.servlet.http.HttpServlet;
+import javax.servlet.http.HttpServletRequest;
+
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.beans.BeansException;
+import org.springframework.beans.factory.NoSuchBeanDefinitionException;
+import org.springframework.beans.factory.NoUniqueBeanDefinitionException;
+import org.springframework.web.context.WebApplicationContext;
+import org.springframework.web.context.support.WebApplicationContextUtils;
+
+import com.datentechnik.process_engine.ProcessEngine;
+import com.datentechnik.process_engine.ProcessInstance;
+import com.datentechnik.process_engine.api.ExecutionContext;
+
+/**
+ * Abstract HttpServlet that provides means for retrieving the process engine (Spring Web required) as well as
+ * retrieving the underlying process instance and execution context evaluating a certain request parameter.
+ *
+ * @author tknall
+ *
+ */
+public abstract class AbstractAuthSourceServlet extends HttpServlet {
+
+ private static final long serialVersionUID = 1L;
+
+ private ProcessEngine processEngine;
+
+ /**
+ * Returns the name of the request parameter representing the respective instance id.
+ * <p/>Default is {@code processInstanceId}.
+ * @return The request parameter name.
+ */
+ public String getProcessInstanceIdParameterName() {
+ return "processInstanceId";
+ }
+
+ /**
+ * Returns the underlying process engine instance.
+ *
+ * @return The process engine (never {@code null}).
+ * @throws NoSuchBeanDefinitionException
+ * if no {@link ProcessEngine} bean was found.
+ * @throws NoUniqueBeanDefinitionException
+ * if more than one {@link ProcessEngine} bean was found.
+ * @throws BeansException
+ * if a problem getting the {@link ProcessEngine} bean occurred.
+ * @throws IllegalStateException
+ * if the Spring WebApplicationContext was not found, which means that the servlet is used outside a
+ * Spring web environment.
+ */
+ public synchronized ProcessEngine getProcessEngine() {
+ if (processEngine == null) {
+ WebApplicationContext ctx = WebApplicationContextUtils.getWebApplicationContext(getServletContext());
+ if (ctx == null) {
+ throw new IllegalStateException(
+ "Unable to find Spring WebApplicationContext. Servlet needs to be executed within a Spring web environment.");
+ }
+ processEngine = ctx.getBean(ProcessEngine.class);
+ }
+ return processEngine;
+ }
+
+ /**
+ * Retrieves the process instance referenced by the request parameter {@link #getProcessInstanceIdParameterName()}.
+ *
+ * @param request
+ * The HttpServletRequest.
+ * @return The process instance (never {@code null}).
+ * @throws NoSuchBeanDefinitionException
+ * if no {@link ProcessEngine} bean was found.
+ * @throws NoUniqueBeanDefinitionException
+ * if more than one {@link ProcessEngine} bean was found.
+ * @throws BeansException
+ * if a problem getting the {@link ProcessEngine} bean occurred.
+ * @throws IllegalStateException
+ * if the Spring WebApplicationContext was not found, which means that the servlet is used outside a
+ * Spring web environment.
+ * @throws IllegalArgumentException
+ * in case the process instance id referenced by the request parameter
+ * {@link #getProcessInstanceIdParameterName()} does not exist.
+ */
+ public ProcessInstance getProcessInstance(HttpServletRequest request) {
+ String processInstanceId = StringUtils.trimToNull(request.getParameter(getProcessInstanceIdParameterName()));
+ if (processInstanceId == null) {
+ throw new IllegalArgumentException("Missing request parameter '" + getProcessInstanceIdParameterName() + "'.");
+ }
+ return getProcessEngine().getProcessInstance(processInstanceId);
+ }
+
+ /**
+ * Retrieves the execution context for the respective process instance referenced by the request parameter
+ * {@link #getProcessInstanceIdParameterName()}.
+ *
+ * @param request
+ * The HttpServletRequest.
+ * @return The execution context (never {@code null}).
+ * @throws NoSuchBeanDefinitionException
+ * if no {@link ProcessEngine} bean was found.
+ * @throws NoUniqueBeanDefinitionException
+ * if more than one {@link ProcessEngine} bean was found.
+ * @throws BeansException
+ * if a problem getting the {@link ProcessEngine} bean occurred.
+ * @throws IllegalStateException
+ * if the Spring WebApplicationContext was not found, which means that the servlet is used outside a
+ * Spring web environment.
+ * @throws IllegalArgumentException
+ * in case the process instance id referenced by the request parameter
+ * {@link #getProcessInstanceIdParameterName()} does not exist.
+ */
+ public ExecutionContext getExecutionContext(HttpServletRequest request) {
+ return getProcessInstance(request).getExecutionContext();
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/springweb/AbstractSpringWebSupportedTask.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/springweb/AbstractSpringWebSupportedTask.java
new file mode 100644
index 000000000..1f7fb7690
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/springweb/AbstractSpringWebSupportedTask.java
@@ -0,0 +1,73 @@
+package at.gv.egovernment.moa.id.process.springweb;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+
+import org.springframework.web.context.request.RequestAttributes;
+import org.springframework.web.context.request.RequestContextHolder;
+import org.springframework.web.context.request.ServletRequestAttributes;
+import org.springframework.web.filter.RequestContextFilter;
+
+import com.datentechnik.process_engine.api.ExecutionContext;
+import com.datentechnik.process_engine.api.Task;
+
+/**
+ * Abstract task implementation providing {@link HttpServletRequest} and {@link HttpServletResponse}.
+ * <p/>
+ * Note that this abstract task requires the Spring (web) framework including a {@link RequestContextFilter} to be set
+ * within {@code web.xml}.
+ *
+ * <pre>
+ * ...
+ * &lt;filter&gt;
+ * &lt;filter-name&gt;requestContextFilter&lt;/filter-name&gt;
+ * &lt;filter-class&gt;org.springframework.web.filter.RequestContextFilter&lt;/filter-class&gt;
+ * &lt;/filter&gt;
+ * &lt;filter-mapping&gt;
+ * &lt;filter-name&gt;requestContextFilter&lt;/filter-name&gt;
+ * &lt;url-pattern&gt;/*&lt;/url-pattern&gt;
+ * &lt;/filter-mapping&gt;
+ * ...
+ * </pre>
+ *
+ * @author tknall
+ *
+ */
+public abstract class AbstractSpringWebSupportedTask implements Task {
+
+ /**
+ * Executes the task providing the underlying {@link ExecutionContext} {@code executionContext} as well as the
+ * respective {@link HttpServletRequest} and {@link HttpServletResponse}.
+ *
+ * @param executionContext
+ * The execution context (never {@code null}).
+ * @param request
+ * The HttpServletRequest (never {@code null}).
+ * @param response
+ * The HttpServletResponse (never {@code null}).
+ * @throws IllegalStateException
+ * Thrown in case the task is nur being run within the required environment. Refer to javadoc for
+ * further information.
+ * @throws Exception
+ * Thrown in case of error executing the task.
+ */
+ public abstract void execute(ExecutionContext executionContext, HttpServletRequest request,
+ HttpServletResponse response) throws Exception;
+
+ @Override
+ public void execute(ExecutionContext executionContext) throws Exception {
+ RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
+ if (requestAttributes != null && requestAttributes instanceof ServletRequestAttributes) {
+ HttpServletRequest request = ((ServletRequestAttributes) requestAttributes).getRequest();
+ HttpServletResponse response = ((ServletRequestAttributes) requestAttributes).getResponse();
+ if (request == null || response == null) {
+ throw new IllegalStateException(
+ "Spring's RequestContextHolder did not provide HttpServletResponse. Did you forget to set the required org.springframework.web.filter.RequestContextFilter in your web.xml.");
+ }
+ execute(executionContext, request, response);
+ } else {
+ throw new IllegalStateException("Task needs to be executed within a Spring web environment.");
+ }
+ }
+
+}
diff --git a/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/support/SecureRandomHolder.java b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/support/SecureRandomHolder.java
new file mode 100644
index 000000000..72677739a
--- /dev/null
+++ b/id/server/idserverlib/src/main/java/at/gv/egovernment/moa/id/process/support/SecureRandomHolder.java
@@ -0,0 +1,35 @@
+package at.gv.egovernment.moa.id.process.support;
+
+import java.security.NoSuchAlgorithmException;
+import java.security.SecureRandom;
+
+/**
+ * Holder for a secure random instance following the initialization on demand holder design pattern. The secure random
+ * instance is a singleton that is initialized on first usage.
+ *
+ * @author tknall
+ *
+ */
+public class SecureRandomHolder {
+
+ private SecureRandomHolder() {
+ }
+
+ private static final SecureRandom SRND_INSTANCE;
+ static {
+ try {
+ SRND_INSTANCE = SecureRandom.getInstance("SHA1PRNG");
+ } catch (NoSuchAlgorithmException e) {
+ throw new RuntimeException("Unable to instantiate SHA1PRNG.", e);
+ }
+ }
+
+ /**
+ * Returns a secure random generator instance.
+ * @return The secure random instance.
+ */
+ public static SecureRandom getInstance() {
+ return SecureRandomHolder.SRND_INSTANCE;
+ }
+
+} \ No newline at end of file