Zwischenstand, compilierbar

git-svn-id: https://joinup.ec.europa.eu/svn/moa-idspss/trunk@69 d688527b-c9ab-4aba-bd8d-4036d912da1d

1 files changed, 162 insertions, 0 deletions

diff --git a/spss.slinterface/WEB-INF/src/at/gv/egovernment/moa/spss/slinterface/XPathUtils.java b/spss.slinterface/WEB-INF/src/at/gv/egovernment/moa/spss/slinterface/XPathUtils.java
new file mode 100644
index 000000000..16e4938ed
--- /dev/null
+++ b/spss.slinterface/WEB-INF/src/at/gv/egovernment/moa/spss/slinterface/XPathUtils.java
@@ -0,0 +1,162 @@
+/*
+ * Created on 02.12.2003
+ *
+ * (c) Stabsstelle IKT-Strategie des Bundes
+ */
+package at.gv.egovernment.moa.spss.slinterface;
+
+import java.util.HashMap;
+import java.util.StringTokenizer;
+
+import org.apache.xml.utils.PrefixResolverDefault;
+import org.apache.xpath.XPath;
+import org.apache.xpath.XPathContext;
+import org.apache.xpath.objects.XObject;
+import org.w3c.dom.Node;
+import org.w3c.dom.NodeList;
+
+/**
+ * @author Gregor Karlinger (mailto:gregor.karlinger@cio.gv.at) 
+ */
+public class XPathUtils 
+{
+  /**
+   * The XPath context for the XPath engine.
+   */
+  protected XPathContext xPathContext_;
+
+  /**
+   * The prefix resolver for the XPath engine.
+   */
+  protected PrefixResolver prefixResolver_;
+
+  /**
+   * The XPath engine.
+   */
+  protected XPath xPath_;
+
+  /* ==================================================================================================== */
+
+  public void setupContext(String xPathExpr, Node namespaceNode, String additionalNSPrefixes)
+    throws Exception
+  {
+
+    try
+    {
+      // Set up a new evaluation context
+      xPathContext_ = new XPathContext();
+
+      // Set up the namespace prefix resolver for the XPath engine
+      prefixResolver_ = new PrefixResolver(namespaceNode, additionalNSPrefixes);
+
+      // Initialize XPath engine
+      xPath_ = new XPath(xPathExpr, null, prefixResolver_, XPath.SELECT, null);
+    }
+    catch (Exception e)
+    {
+      throw new Exception("Setting up XPath evaluation context failed.", e);
+    }
+  }
+
+  /* ---------------------------------------------------------------------------------------------------- */
+
+  public NodeList selectNodeSet(Node contextNode) throws Exception
+  {
+    XObject xObject;
+    try
+    {
+      xObject = xPath_.execute(xPathContext_, contextNode, prefixResolver_);
+      return xObject.nodelist();
+    }
+    catch (Exception e)
+    {
+      throw new Exception("Executing XPath expression failed.", e);
+    }
+  }
+
+  /* ---------------------------------------------------------------------------------------------------- */
+
+  public boolean selectBoolean(Node contextNode) throws Exception
+  {
+    XObject xObject;
+    try
+    {
+      xObject = xPath_.execute(xPathContext_, contextNode, prefixResolver_);
+      return xObject.bool();
+    }
+    catch (Exception e)
+    {
+      throw new Exception("Executing XPath expression failed.", e);
+    }
+  }
+
+  /* ==================================================================================================== */
+
+  /**
+   * Special extension of the {@link org.apache.xml.utils.PrefixResolverDefault} interface. Used to
+   * configure the Apache Xalan XPath engine which is employed as the backbone of this class.
+   */
+  protected class PrefixResolver extends PrefixResolverDefault
+  {
+
+    /**
+     * Contains the additionally specified namespace prefix (key) to namespace URI (value) attributions.
+     */
+    protected HashMap additionalNSPrefixesMap_;
+
+    /* ================================================================================================== */
+
+    /**
+     * Basic constructor.
+     *
+     * @param xpathExpressionContext The namespace declarations in scope for this node will be used to get
+     *                               the namespace uri for a prefix specified in the XPath expression.
+     *
+     * @param additionalNSPrefixes Allows the specification of additional prefix to uri attributions apart
+     *                             from the declarations in scope for the parameter <code>
+     *                             xpathExpressionContext</code>. May be <code>null</code>.
+     */
+    public PrefixResolver(Node xpathExpressionContext, String additionalNSPrefixes) throws Exception
+    {
+      super(xpathExpressionContext);
+      additionalNSPrefixesMap_ = new HashMap();
+
+      // Register the specified additional namespace prefix to namespace uri attributions
+      if (additionalNSPrefixes != null)
+      {
+        StringTokenizer tokenizer = new StringTokenizer(additionalNSPrefixes, " ");
+        while (tokenizer.hasMoreTokens())
+        {
+          String prefix = tokenizer.nextToken();
+          if (!tokenizer.hasMoreTokens())
+          {
+
+            // There must be an even number of tokens in the string
+            throw new Exception("Parameter \"additionalNSPrefixes\" must have an even number of tokens.");
+          }
+          String uri = tokenizer.nextToken();
+          additionalNSPrefixesMap_.put(prefix, uri);
+        }
+      }
+    }
+
+    /* -------------------------------------------------------------------------------------------------- */
+
+    /**
+     * Gets the namespace uri for the specified namespace prefix. The additionally specified prefixes
+     * overrule the prefixes found in the specified namespace node.
+     *
+     * @param prefix The namespace prefix for which a namespace uri should be found.
+     *
+     * @return the namespace uri for the specified namespace prefix.
+     */
+    public String getNamespaceForPrefix(String prefix)
+    {
+      String additionalURI = (String) additionalNSPrefixesMap_.get(prefix);
+      return (additionalURI != null)
+             ? additionalURI
+             : super.getNamespaceForPrefix(prefix);
+    }
+  }
+}
+