diff options
author | Thomas Lenz <thomas.lenz@egiz.gv.at> | 2019-04-23 15:00:40 +0200 |
---|---|---|
committer | Thomas Lenz <thomas.lenz@egiz.gv.at> | 2019-04-23 15:00:40 +0200 |
commit | 02851082661a924adc68230615f61a308705ce2b (patch) | |
tree | bd09998365191ddb065c3c61a0af60d0ec684bda /eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGUIFormBuilderImpl.java | |
parent | 5c1b5b863fe8d6c08cfe0749fed7ce9594827f8a (diff) | |
download | EAAF-Components-02851082661a924adc68230615f61a308705ce2b.tar.gz EAAF-Components-02851082661a924adc68230615f61a308705ce2b.tar.bz2 EAAF-Components-02851082661a924adc68230615f61a308705ce2b.zip |
integrate Spring ModelAndView into EAAF GUI framework
Diffstat (limited to 'eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGUIFormBuilderImpl.java')
-rw-r--r-- | eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGUIFormBuilderImpl.java | 242 |
1 files changed, 242 insertions, 0 deletions
diff --git a/eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGUIFormBuilderImpl.java b/eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGUIFormBuilderImpl.java new file mode 100644 index 00000000..65e13b5a --- /dev/null +++ b/eaaf_core/src/main/java/at/gv/egiz/eaaf/core/impl/gui/AbstractVelocityGUIFormBuilderImpl.java @@ -0,0 +1,242 @@ +/******************************************************************************* + * Copyright 2017 Graz University of Technology + * EAAF-Core Components has been developed in a cooperation between EGIZ, + * A-SIT Plus, A-SIT, and Graz University of Technology. + * + * Licensed under the EUPL, Version 1.2 or - as soon they will be approved by + * the European Commission - subsequent versions of the EUPL (the "Licence"); + * You may not use this work except in compliance with the Licence. + * You may obtain a copy of the Licence at: + * https://joinup.ec.europa.eu/news/understanding-eupl-v12 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the Licence is distributed on an "AS IS" basis, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the Licence for the specific language governing permissions and + * limitations under the Licence. + * + * This product combines work with different licenses. See the "NOTICE" text + * file for details on the various modules and licenses. + * The "NOTICE" text file is part of the distribution. Any derivative works + * that you distribute must include a readable copy of the "NOTICE" text file. + *******************************************************************************/ +/******************************************************************************* + *******************************************************************************/ +/******************************************************************************* + *******************************************************************************/ +package at.gv.egiz.eaaf.core.impl.gui; + +import java.io.BufferedReader; +import java.io.IOException; +import java.io.InputStream; +import java.io.InputStreamReader; +import java.io.StringWriter; +import java.util.Iterator; +import java.util.Map; +import java.util.Map.Entry; + +import javax.servlet.http.HttpServletRequest; +import javax.servlet.http.HttpServletResponse; + +import org.apache.commons.lang3.StringUtils; +import org.apache.velocity.VelocityContext; +import org.apache.velocity.app.VelocityEngine; +import org.slf4j.Logger; +import org.slf4j.LoggerFactory; + +import at.gv.egiz.eaaf.core.api.data.EAAFConstants; +import at.gv.egiz.eaaf.core.api.gui.IGUIBuilderConfiguration; +import at.gv.egiz.eaaf.core.api.gui.IVelocityGUIBuilderConfiguration; +import at.gv.egiz.eaaf.core.api.gui.IVelocityGuiFormBuilder; +import at.gv.egiz.eaaf.core.exceptions.GUIBuildException; +import at.gv.egiz.eaaf.core.impl.gui.velocity.VelocityProvider; + +/** + * @author tlenz + * + */ +public abstract class AbstractVelocityGUIFormBuilderImpl implements IVelocityGuiFormBuilder { + private static final Logger log = LoggerFactory.getLogger(AbstractVelocityGUIFormBuilderImpl.class); + private static final String DEFAULT_CONTENT_TYPE = EAAFConstants.CONTENTTYPE_HTML_UTF8; + + private VelocityEngine engine; + + public AbstractVelocityGUIFormBuilderImpl() throws GUIBuildException { + try { + engine = VelocityProvider.getClassPathVelocityEngine(); + + } catch (final Exception e) { + log.error("Initialization of Velocity-Engine to render GUI components FAILED.", e); + throw new GUIBuildException("Initialization of Velocity-Engine to render GUI components FAILED.", e); + + } + + } + + @Override + public final void build(HttpServletRequest httpReq, HttpServletResponse httpResp, IGUIBuilderConfiguration config, + String loggerName) throws GUIBuildException { + if (config instanceof IVelocityGUIBuilderConfiguration) + build(httpReq, httpResp, config, loggerName); + else + throw new IllegalStateException(this.getClass().getName() + " needs a " + IVelocityGUIBuilderConfiguration.class.getName()); + + + } + + @Override + public final void build(HttpServletRequest httpReq, HttpServletResponse httpResp, IGUIBuilderConfiguration config, + String contentType, String loggerName) throws GUIBuildException { + if (config instanceof IVelocityGUIBuilderConfiguration) + build(httpReq, httpResp, config, loggerName); + else + throw new IllegalStateException(this.getClass().getName() + " needs a " + IVelocityGUIBuilderConfiguration.class.getName()); + + } + + @Override + public void build(HttpServletRequest httpReq, HttpServletResponse httpResp, IVelocityGUIBuilderConfiguration config, String loggerName) throws GUIBuildException { + build(httpReq, httpResp, config, getInternalContentType(config), loggerName); + + } + + @Override + public void build(HttpServletRequest httpReq, HttpServletResponse httpResp, IVelocityGUIBuilderConfiguration config, + String contentType, String loggerName) throws GUIBuildException { + + InputStream is = null; + try { + final String viewName = config.getViewName(); + is = getTemplateInputStream(config); + + //build Velocity Context from input paramters + final VelocityContext context = buildContextFromViewParams(config.getViewParameters()); + + //evaluate template + final StringWriter writer = new StringWriter(); + engine.evaluate(context, writer, loggerName, new BufferedReader(new InputStreamReader(is))); + + //write template to response + final byte[] content = writer.toString().getBytes("UTF-8"); + httpResp.setStatus(HttpServletResponse.SC_OK); + httpResp.setContentLength(content.length); + httpResp.setContentType(contentType); + httpResp.getOutputStream().write(content); + + if (log.isTraceEnabled()) { + log.trace("Write Content for viewName:" + viewName + + ". Contentsize:" + String.valueOf(content.length) + + " BufferSize:" + httpResp.getBufferSize() + + " ContentType:" + contentType); + for (final String el : httpResp.getHeaderNames()) + log.trace(" * Headername:" + el + " Value:" + httpResp.getHeader(el)); + + } + + } catch (final IOException e) { + log.error("GUI form-builder has an internal error.", e); + throw new GUIBuildException("GUI form-builder has an internal error.", e); + + } finally { + if (is != null) + try { + is.close(); + + } catch (final IOException e) { + log.error("Can NOT close GUI-Template InputStream.", e); + + } + } + + } + + /** + * Generate a new {@link VelocityContext} and populate it with MOA-ID GUI parameters + * + * @param config + * @return + */ + @Override + public VelocityContext generateVelocityContextFromConfiguration(IVelocityGUIBuilderConfiguration config) { + return buildContextFromViewParams(config.getViewParameters()); + + } + + /** + * Load the template from different resources + * + * @param config + * @return An {@link InputStream} but never null. The {@link InputStream} had to be closed be the invoking method + * @throws GUIBuildException + */ + @Override + public InputStream getTemplateInputStream(IVelocityGUIBuilderConfiguration config) throws GUIBuildException { + InputStream is = config.getTemplate(config.getViewName()); + if (is == null) { + log.trace("Loading GUI template:" + config.getViewName() + " from default resources ... "); + is = getInternalTemplate(config); + + if (is == null) { + log.warn("No GUI with viewName:" + config.getViewName() + " FOUND."); + throw new GUIBuildException("No GUI with viewName:" + config.getViewName() + " FOUND."); + + } + } + return is; + + } + + /** + * Load an internal template from default resources + * + * @param config + * @return + * @throws GUIBuildException + */ + abstract protected InputStream getInternalTemplate(IVelocityGUIBuilderConfiguration config) throws GUIBuildException; + + + /** + * @return + */ + protected String getInternalClasspathTemplateDir(IVelocityGUIBuilderConfiguration config, String defaultClassPathDir) { + String dir = config.getClasspathTemplateDir(); + if (dir != null) { + if (!dir.endsWith("/")) + dir += "/"; + + return dir; + + } else + return defaultClassPathDir; + } + + /** + * @param viewParams + * @return + */ + private VelocityContext buildContextFromViewParams(Map<String, Object> viewParams) { + final VelocityContext context = new VelocityContext(); + + if (viewParams != null) { + final Iterator<Entry<String, Object>> interator = viewParams.entrySet().iterator(); + while (interator.hasNext()) { + final Entry<String, Object> el = interator.next(); + context.put(el.getKey(), el.getValue()); + } + + } + + return context; + } + + private String getInternalContentType(IGUIBuilderConfiguration config) { + if (StringUtils.isEmpty(config.getDefaultContentType())) + return DEFAULT_CONTENT_TYPE; + + else + return config.getDefaultContentType(); + + } + +} |