src/java.xml/share/classes/com/sun/org/apache/xpath/internal/jaxp/XPathExpressionImpl.java

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@@ -1,77 +1,50 @@
 /*
- * reserved comment block
- * DO NOT REMOVE OR ALTER!
+ * Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
  */
 /*
- * Copyright 1999-2004 The Apache Software Foundation.
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
  *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
  *     http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-// $Id: XPathExpressionImpl.java,v 1.3 2005/09/27 09:40:43 sunithareddy Exp $
 
 package com.sun.org.apache.xpath.internal.jaxp;
 
-import com.sun.org.apache.xpath.internal.*;
-import javax.xml.transform.TransformerException;
-
-import com.sun.org.apache.xpath.internal.objects.XObject;
-import com.sun.org.apache.xml.internal.dtm.DTM;
-import com.sun.org.apache.xml.internal.utils.PrefixResolver;
-import com.sun.org.apache.xpath.internal.res.XPATHErrorResources;
-import com.sun.org.apache.xalan.internal.res.XSLMessages;
-import com.sun.org.apache.xalan.internal.utils.FactoryImpl;
 import com.sun.org.apache.xalan.internal.utils.FeatureManager;
-
-import javax.xml.namespace.NamespaceContext;
+import com.sun.org.apache.xpath.internal.objects.XObject;
 import javax.xml.namespace.QName;
-import javax.xml.xpath.XPathExpressionException;
+import javax.xml.transform.TransformerException;
 import javax.xml.xpath.XPathConstants;
+import javax.xml.xpath.XPathEvaluationResult;
+import javax.xml.xpath.XPathExpression;
+import javax.xml.xpath.XPathExpressionException;
 import javax.xml.xpath.XPathFunctionResolver;
 import javax.xml.xpath.XPathVariableResolver;
-import javax.xml.xpath.XPathConstants;
-
-import org.w3c.dom.Node;
 import org.w3c.dom.Document;
-import org.w3c.dom.DOMImplementation;
-import org.w3c.dom.traversal.NodeIterator;
-import javax.xml.parsers.DocumentBuilderFactory;
-import javax.xml.parsers.DocumentBuilder;
-
+import org.w3c.dom.Node;
 import org.xml.sax.InputSource;
 
 /**
  * The XPathExpression interface encapsulates a (compiled) XPath expression.
  *
  * @author  Ramesh Mandava
  */
-public class XPathExpressionImpl  implements javax.xml.xpath.XPathExpression{
+public class XPathExpressionImpl extends XPathImplUtil implements XPathExpression {
 
-    private XPathFunctionResolver functionResolver;
-    private XPathVariableResolver variableResolver;
-    private JAXPPrefixResolver prefixResolver;
     private com.sun.org.apache.xpath.internal.XPath xpath;
 
-    // By default Extension Functions are allowed in XPath Expressions. If
-    // Secure Processing Feature is set on XPathFactory then the invocation of
-    // extensions function need to throw XPathFunctionException
-    private boolean featureSecureProcessing = false;
-
-    private boolean useServicesMechanism = true;
-
-    private final FeatureManager featureManager;
-
     /** Protected constructor to prevent direct instantiation; use compile()
      * from the context.
      */
     protected XPathExpressionImpl() {
         this(null, null, null, null,

@@ -79,301 +52,118 @@
     };
 
     protected XPathExpressionImpl(com.sun.org.apache.xpath.internal.XPath xpath,
             JAXPPrefixResolver prefixResolver,
             XPathFunctionResolver functionResolver,
-            XPathVariableResolver variableResolver ) {
+            XPathVariableResolver variableResolver) {
         this(xpath, prefixResolver, functionResolver, variableResolver,
              false, true, new FeatureManager());
     };
 
     protected XPathExpressionImpl(com.sun.org.apache.xpath.internal.XPath xpath,
             JAXPPrefixResolver prefixResolver,XPathFunctionResolver functionResolver,
             XPathVariableResolver variableResolver, boolean featureSecureProcessing,
-            boolean useServicesMechanism, FeatureManager featureManager ) {
+            boolean useServiceMechanism, FeatureManager featureManager) {
         this.xpath = xpath;
         this.prefixResolver = prefixResolver;
         this.functionResolver = functionResolver;
         this.variableResolver = variableResolver;
         this.featureSecureProcessing = featureSecureProcessing;
-        this.useServicesMechanism = useServicesMechanism;
+        this.useServiceMechanism = useServiceMechanism;
         this.featureManager = featureManager;
     };
 
-    public void setXPath (com.sun.org.apache.xpath.internal.XPath xpath ) {
+    public void setXPath (com.sun.org.apache.xpath.internal.XPath xpath) {
         this.xpath = xpath;
     }
 
     public Object eval(Object item, QName returnType)
             throws javax.xml.transform.TransformerException {
-        XObject resultObject = eval ( item );
-        return getResultAsType( resultObject, returnType );
+        XObject resultObject = eval(item, xpath);
+        return getResultAsType(resultObject, returnType);
     }
 
-    private XObject eval ( Object contextItem )
-            throws javax.xml.transform.TransformerException {
-        com.sun.org.apache.xpath.internal.XPathContext xpathSupport = null;
-        if ( functionResolver != null ) {
-            JAXPExtensionsProvider jep = new JAXPExtensionsProvider(
-                    functionResolver, featureSecureProcessing, featureManager );
-            xpathSupport = new com.sun.org.apache.xpath.internal.XPathContext( jep );
-        } else {
-            xpathSupport = new com.sun.org.apache.xpath.internal.XPathContext();
-        }
-
-        xpathSupport.setVarStack(new JAXPVariableStack(variableResolver));
-        XObject xobj = null;
-
-        Node contextNode = (Node)contextItem;
-        // We always need to have a ContextNode with Xalan XPath implementation
-        // To allow simple expression evaluation like 1+1 we are setting
-        // dummy Document as Context Node
-
-        if ( contextNode == null )
-            xobj = xpath.execute(xpathSupport, DTM.NULL, prefixResolver);
-        else
-            xobj = xpath.execute(xpathSupport, contextNode, prefixResolver);
-
-        return xobj;
-    }
-
-
-    /**
-     * <p>Evaluate the compiled XPath expression in the specified context and
-     *  return the result as the specified type.</p>
-     *
-     * <p>See "Evaluation of XPath Expressions" section of JAXP 1.3 spec
-     * for context item evaluation,
-     * variable, function and QName resolution and return type conversion.</p>
-     *
-     * <p>If <code>returnType</code> is not one of the types defined
-     * in {@link XPathConstants},
-     * then an <code>IllegalArgumentException</code> is thrown.</p>
-     *
-     * <p>If a <code>null</code> value is provided for
-     * <code>item</code>, an empty document will be used for the
-     * context.
-     * If <code>returnType</code> is <code>null</code>, then a
-     * <code>NullPointerException</code> is thrown.</p>
-     *
-     * @param item The starting context (node or node list, for example).
-     * @param returnType The desired return type.
-     *
-     * @return The <code>Object</code> that is the result of evaluating the
-     * expression and converting the result to
-     *   <code>returnType</code>.
-     *
-     * @throws XPathExpressionException If the expression cannot be evaluated.
-     * @throws IllegalArgumentException If <code>returnType</code> is not one
-     * of the types defined in {@link XPathConstants}.
-     * @throws NullPointerException If  <code>returnType</code> is
-     * <code>null</code>.
-     */
+    @Override
     public Object evaluate(Object item, QName returnType)
         throws XPathExpressionException {
-        //Validating parameters to enforce constraints defined by JAXP spec
-        if ( returnType == null ) {
-           //Throwing NullPointerException as defined in spec
-            String fmsg = XSLMessages.createXPATHMessage(
-                    XPATHErrorResources.ER_ARG_CANNOT_BE_NULL,
-                    new Object[] {"returnType"} );
-            throw new NullPointerException( fmsg );
-        }
-        // Checking if requested returnType is supported. returnType need to be
-        // defined in XPathConstants
-        if ( !isSupported ( returnType ) ) {
-            String fmsg = XSLMessages.createXPATHMessage(
-                    XPATHErrorResources.ER_UNSUPPORTED_RETURN_TYPE,
-                    new Object[] { returnType.toString() } );
-            throw new IllegalArgumentException ( fmsg );
-        }
+        isSupported(returnType);
         try {
-            return eval( item, returnType);
-        } catch ( java.lang.NullPointerException npe ) {
+            return eval(item, returnType);
+        } catch (java.lang.NullPointerException npe) {
             // If VariableResolver returns null Or if we get
             // NullPointerException at this stage for some other reason
             // then we have to reurn XPathException
-            throw new XPathExpressionException ( npe );
-        } catch ( javax.xml.transform.TransformerException te ) {
+            throw new XPathExpressionException (npe);
+        } catch (javax.xml.transform.TransformerException te) {
             Throwable nestedException = te.getException();
-            if ( nestedException instanceof javax.xml.xpath.XPathFunctionException ) {
+            if (nestedException instanceof javax.xml.xpath.XPathFunctionException) {
                 throw (javax.xml.xpath.XPathFunctionException)nestedException;
             } else {
                 // For any other exceptions we need to throw
-                // XPathExpressionException ( as per spec )
-                throw new XPathExpressionException( te);
+                // XPathExpressionException (as per spec)
+                throw new XPathExpressionException(te);
             }
         }
-
     }
 
-    /**
-     * <p>Evaluate the compiled XPath expression in the specified context and
-     * return the result as a <code>String</code>.</p>
-     *
-     * <p>This method calls {@link #evaluate(Object item, QName returnType)}
-     * with a <code>returnType</code> of
-     * {@link XPathConstants#STRING}.</p>
-     *
-     * <p>See "Evaluation of XPath Expressions" section of JAXP 1.3 spec
-     *  for context item evaluation,
-     * variable, function and QName resolution and return type conversion.</p>
-     *
-     * <p>If a <code>null</code> value is provided for
-     * <code>item</code>, an empty document will be used for the
-     * context.
-     *
-     * @param item The starting context (node or node list, for example).
-     *
-     * @return The <code>String</code> that is the result of evaluating the
-     * expression and converting the result to a
-     *   <code>String</code>.
-     *
-     * @throws XPathExpressionException If the expression cannot be evaluated.
-     */
+
+    @Override
     public String evaluate(Object item)
         throws XPathExpressionException {
-        return (String)this.evaluate( item, XPathConstants.STRING );
+        return (String)this.evaluate(item, XPathConstants.STRING);
     }
 
-
-
-    static DocumentBuilderFactory dbf = null;
-    static DocumentBuilder db = null;
-    static Document d = null;
-
-    /**
-     * <p>Evaluate the compiled XPath expression in the context of the
-     * specified <code>InputSource</code> and return the result as the
-     *  specified type.</p>
-     *
-     * <p>This method builds a data model for the {@link InputSource} and calls
-     * {@link #evaluate(Object item, QName returnType)} on the resulting
-     * document object.</p>
-     *
-     * <p>See "Evaluation of XPath Expressions" section of JAXP 1.3 spec
-     *  for context item evaluation,
-     * variable, function and QName resolution and return type conversion.</p>
-     *
-     * <p>If <code>returnType</code> is not one of the types defined in
-     * {@link XPathConstants},
-     * then an <code>IllegalArgumentException</code> is thrown.</p>
-     *
-     *<p>If <code>source</code> or <code>returnType</code> is <code>null</code>,
-     * then a <code>NullPointerException</code> is thrown.</p>
-     *
-     * @param source The <code>InputSource</code> of the document to evaluate
-     * over.
-     * @param returnType The desired return type.
-     *
-     * @return The <code>Object</code> that is the result of evaluating the
-     * expression and converting the result to
-     *   <code>returnType</code>.
-     *
-     * @throws XPathExpressionException If the expression cannot be evaluated.
-     * @throws IllegalArgumentException If <code>returnType</code> is not one
-     * of the types defined in {@link XPathConstants}.
-     * @throws NullPointerException If  <code>source</code> or
-     * <code>returnType</code> is <code>null</code>.
-     */
+    @Override
     public Object evaluate(InputSource source, QName returnType)
         throws XPathExpressionException {
-        if ( ( source == null ) || ( returnType == null ) ) {
-            String fmsg = XSLMessages.createXPATHMessage(
-                    XPATHErrorResources.ER_SOURCE_RETURN_TYPE_CANNOT_BE_NULL,
-                    null );
-            throw new NullPointerException ( fmsg );
-        }
-        // Checking if requested returnType is supported. returnType need to be
-        // defined in XPathConstants
-        if ( !isSupported ( returnType ) ) {
-            String fmsg = XSLMessages.createXPATHMessage(
-                    XPATHErrorResources.ER_UNSUPPORTED_RETURN_TYPE,
-                    new Object[] { returnType.toString() } );
-            throw new IllegalArgumentException ( fmsg );
-        }
+        isSupported (returnType);
         try {
-            if ( dbf == null ) {
-                dbf = FactoryImpl.getDOMFactory(useServicesMechanism);
-                dbf.setNamespaceAware( true );
-                dbf.setValidating( false );
+            Document document = getDocument(source);
+            return eval(document, returnType);
+        } catch (TransformerException e) {
+            throw new XPathExpressionException(e);
             }
-            db = dbf.newDocumentBuilder();
-            Document document = db.parse( source );
-            return eval(  document, returnType );
-        } catch ( Exception e ) {
-            throw new XPathExpressionException ( e );
         }
-    }
 
-    /**
-     * <p>Evaluate the compiled XPath expression in the context of the specified <code>InputSource</code> and return the result as a
-     * <code>String</code>.</p>
-     *
-     * <p>This method calls {@link #evaluate(InputSource source, QName returnType)} with a <code>returnType</code> of
-     * {@link XPathConstants#STRING}.</p>
-     *
-     * <p>See "Evaluation of XPath Expressions" section of JAXP 1.3 spec
-     * for context item evaluation,
-     * variable, function and QName resolution and return type conversion.</p>
-     *
-     * <p>If <code>source</code> is <code>null</code>, then a <code>NullPointerException</code> is thrown.</p>
-     *
-     * @param source The <code>InputSource</code> of the document to evaluate over.
-     *
-     * @return The <code>String</code> that is the result of evaluating the expression and converting the result to a
-     *   <code>String</code>.
-     *
-     * @throws XPathExpressionException If the expression cannot be evaluated.
-     * @throws NullPointerException If  <code>source</code> is <code>null</code>.
-     */
+    @Override
     public String evaluate(InputSource source)
         throws XPathExpressionException {
-        return (String)this.evaluate( source, XPathConstants.STRING );
+        return (String)this.evaluate(source, XPathConstants.STRING);
     }
 
-    private boolean isSupported( QName returnType ) {
-        // XPathConstants.STRING
-        if ( ( returnType.equals( XPathConstants.STRING ) ) ||
-             ( returnType.equals( XPathConstants.NUMBER ) ) ||
-             ( returnType.equals( XPathConstants.BOOLEAN ) ) ||
-             ( returnType.equals( XPathConstants.NODE ) ) ||
-             ( returnType.equals( XPathConstants.NODESET ) )  ) {
+    @Override
+    public <T>T evaluateExpression(Object item, Class<T> type)
+        throws XPathExpressionException {
+        isSupportedClassType(type);
 
-            return true;
+        try {
+            XObject resultObject = eval(item, xpath);
+            if (type.isAssignableFrom(XPathEvaluationResult.class)) {
+                return getXPathResult(resultObject, type);
+            } else {
+                return XPathResultImpl.getValue(resultObject, type);
         }
-        return false;
-     }
 
-     private Object getResultAsType( XObject resultObject, QName returnType )
-        throws javax.xml.transform.TransformerException {
-        // XPathConstants.STRING
-        if ( returnType.equals( XPathConstants.STRING ) ) {
-            return resultObject.str();
+        } catch (javax.xml.transform.TransformerException te) {
+            throw new XPathExpressionException(te);
         }
-        // XPathConstants.NUMBER
-        if ( returnType.equals( XPathConstants.NUMBER ) ) {
-            return new Double ( resultObject.num());
         }
-        // XPathConstants.BOOLEAN
-        if ( returnType.equals( XPathConstants.BOOLEAN ) ) {
-            return new Boolean( resultObject.bool());
+
+    @Override
+    public XPathEvaluationResult<?> evaluateExpression(Object item)
+        throws XPathExpressionException {
+        return evaluateExpression(item, XPathEvaluationResult.class);
         }
-        // XPathConstants.NODESET ---ORdered, UNOrdered???
-        if ( returnType.equals( XPathConstants.NODESET ) ) {
-            return resultObject.nodelist();
+
+    @Override
+    public <T>T  evaluateExpression(InputSource source, Class<T> type)
+            throws XPathExpressionException {
+        Document document = getDocument(source);
+        return evaluateExpression(document, type);
         }
-        // XPathConstants.NODE
-        if ( returnType.equals( XPathConstants.NODE ) ) {
-            NodeIterator ni = resultObject.nodeset();
-            //Return the first node, or null
-            return ni.nextNode();
-        }
-        // If isSupported check is already done then the execution path
-        // shouldn't come here. Being defensive
-        String fmsg = XSLMessages.createXPATHMessage(
-                XPATHErrorResources.ER_UNSUPPORTED_RETURN_TYPE,
-                new Object[] { returnType.toString()});
-        throw new IllegalArgumentException ( fmsg );
-    }
 
+    @Override
+    public XPathEvaluationResult<?> evaluateExpression(InputSource source)
+        throws XPathExpressionException {
+        return evaluateExpression(source, XPathEvaluationResult.class);
+    }
  }