src/java.xml/share/classes/javax/xml/xpath/XPathExpression.java
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@@ -1,7 +1,7 @@
/*
- * Copyright (c) 2003, 2005, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2003, 2015, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
@@ -23,15 +23,15 @@
* questions.
*/
package javax.xml.xpath;
-import org.xml.sax.InputSource;
import javax.xml.namespace.QName;
+import org.xml.sax.InputSource;
/**
- * <p><code>XPathExpression</code> provides access to compiled XPath expressions.</p>
+ * <p>{@code XPathExpression} provides access to compiled XPath expressions.</p>
*
* <a name="XPathExpression-evaluation"/>
* <table border="1" cellpadding="2">
* <thead>
* <tr>
@@ -51,20 +51,20 @@
* <tr>
* <td>variables</td>
* <td>
* If the expression contains a variable reference, its value will be found through the {@link XPathVariableResolver}.
* An {@link XPathExpressionException} is raised if the variable resolver is undefined or
- * the resolver returns <code>null</code> for the variable.
+ * the resolver returns {@code null} for the variable.
* The value of a variable must be immutable through the course of any single evaluation.</p>
* </td>
* </tr>
* <tr>
* <td>functions</td>
* <td>
* If the expression contains a function reference, the function will be found through the {@link XPathFunctionResolver}.
* An {@link XPathExpressionException} is raised if the function resolver is undefined or
- * the function resolver returns <code>null</code> for the function.</p>
+ * the function resolver returns {@code null} for the function.</p>
* </td>
* </tr>
* <tr>
* <td>QNames</td>
* <td>
@@ -82,13 +82,13 @@
* </table>
*
* <p>An XPath expression is not thread-safe and not reentrant.
* In other words, it is the application's responsibility to make
* sure that one {@link XPathExpression} object is not used from
- * more than one thread at any given time, and while the <code>evaluate</code>
+ * more than one thread at any given time, and while the {@code evaluate}
* method is invoked, applications may not recursively call
- * the <code>evaluate</code> method.
+ * the {@code evaluate} method.
* <p>
*
* @author <a href="mailto:Norman.Walsh@Sun.com">Norman Walsh</a>
* @author <a href="mailto:Jeff.Suttor@Sun.com">Jeff Suttor</a>
* @see <a href="http://www.w3.org/TR/xpath#section-Expressions">XML Path Language (XPath) Version 1.0, Expressions</a>
@@ -100,101 +100,286 @@
* <p>Evaluate the compiled XPath expression in the specified context and return the result as the specified type.</p>
*
* <p>See <a href="#XPathExpression-evaluation">Evaluation of XPath Expressions</a> 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>
+ * The parameter {@code item} represents the context the XPath expression
+ * will be operated on. The type of the context is implementation-dependent.
+ * If the value is {@code null}, the operation must have no dependency on
+ * the context, otherwise an XPathExpressionException will be thrown.
*
- * <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>
+ * @implNote
+ * The type of the context is usually {@link org.w3c.dom.Node}.
*
- * @param item The starting context (a node, for example).
- * @param returnType The desired return type.
+ * @param item The context the XPath expression will be evaluated in.
+ * @param returnType The result type expected to be returned by the XPath expression.
*
- * @return The <code>Object</code> that is the result of evaluating the expression and converting the result to
- * <code>returnType</code>.
+ * @return The {@code Object} that is the result of evaluating the expression and converting the result to
+ * {@code returnType}.
*
* @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>.
+ * @throws IllegalArgumentException If {@code returnType} is not one of the types defined in {@link XPathConstants}.
+ * @throws NullPointerException If {@code returnType} is {@code null}.
*/
public Object evaluate(Object item, QName returnType)
throws XPathExpressionException;
/**
- * <p>Evaluate the compiled XPath expression in the specified context and return the result as a <code>String</code>.</p>
+ * <p>Evaluate the compiled XPath expression in the specified context and return the result as a {@code String}.</p>
*
- * <p>This method calls {@link #evaluate(Object item, QName returnType)} with a <code>returnType</code> of
+ * <p>This method calls {@link #evaluate(Object item, QName returnType)} with a {@code returnType} of
* {@link XPathConstants#STRING}.</p>
*
* <p>See <a href="#XPathExpression-evaluation">Evaluation of XPath Expressions</a> 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.
+ * <p>
+ * The parameter {@code item} represents the context the XPath expression
+ * will be operated on. The type of the context is implementation-dependent.
+ * If the value is {@code null}, the operation must have no dependency on
+ * the context, otherwise an XPathExpressionException will be thrown.
*
- * @param item The starting context (a node, for example).
+ * @implNote
+ * The type of the context is usually {@link org.w3c.dom.Node}.
*
- * @return The <code>String</code> that is the result of evaluating the expression and converting the result to a
- * <code>String</code>.
+ * @param item The context the XPath expression will be evaluated in.
*
+ * @return The result of evaluating an XPath expression as a {@code String}.
+ *
* @throws XPathExpressionException If the expression cannot be evaluated.
*/
public String evaluate(Object item)
throws XPathExpressionException;
/**
- * <p>Evaluate the compiled XPath expression in the context of the specified <code>InputSource</code> and return the result as the
+ * <p>Evaluate the compiled XPath expression in the context of the specified {@code InputSource} 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 <a href="#XPathExpression-evaluation">Evaluation of XPath Expressions</a> 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 returnType} is not one of the types defined in {@link XPathConstants},
+ * then an {@code IllegalArgumentException} is thrown.</p>
*
- * <p>If <code>source</code> or <code>returnType</code> is <code>null</code>,
- * then a <code>NullPointerException</code> is thrown.</p>
+ * <p>If {@code source} or {@code returnType} is {@code null},
+ * then a {@code NullPointerException} is thrown.</p>
*
- * @param source The <code>InputSource</code> of the document to evaluate over.
+ * @param source The {@code InputSource} 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>.
+ * @return The {@code Object} that is the result of evaluating the expression and converting the result to
+ * {@code returnType}.
*
* @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>.
+ * @throws IllegalArgumentException If {@code returnType} is not one of the types defined in {@link XPathConstants}.
+ * @throws NullPointerException If {@code source or returnType} is {@code null}.
*/
public Object evaluate(InputSource source, QName returnType)
throws XPathExpressionException;
/**
- * <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>Evaluate the compiled XPath expression in the context of the specified {@code InputSource} and return the result as a
+ * {@code String}.</p>
*
- * <p>This method calls {@link #evaluate(InputSource source, QName returnType)} with a <code>returnType</code> of
+ * <p>This method calls {@link #evaluate(InputSource source, QName returnType)} with a {@code returnType} of
* {@link XPathConstants#STRING}.</p>
*
* <p>See <a href="#XPathExpression-evaluation">Evaluation of XPath Expressions</a> 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>
+ * <p>If {@code source} is {@code null}, then a {@code NullPointerException} is thrown.</p>
*
- * @param source The <code>InputSource</code> of the document to evaluate over.
+ * @param source The {@code InputSource} 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>.
+ * @return The {@code String} that is the result of evaluating the expression and converting the result to a
+ * {@code String}.
*
* @throws XPathExpressionException If the expression cannot be evaluated.
- * @throws NullPointerException If <code>source</code> is <code>null</code>.
+ * @throws NullPointerException If {@code source} is {@code null}.
*/
public String evaluate(InputSource source)
throws XPathExpressionException;
+
+ /**
+ * Evaluate the compiled XPath expression in the specified context, and return
+ * the result with the type specified through the {@code class type}.
+ *
+ * <p>
+ * The parameter {@code item} represents the context the XPath expression
+ * will be operated on. The type of the context is implementation-dependent.
+ * If the value is {@code null}, the operation must have no dependency on
+ * the context, otherwise an XPathExpressionException will be thrown.
+ *
+ * @implNote
+ * The type of the context is usually {@link org.w3c.dom.Node}.
+ *
+ * @implSpec
+ * The default implementation in the XPath API is equivalent to:
+ * <pre> {@code
+ * (T)evaluate(item, XPathEvaluationResult.XPathResultType.getQNameType(type));
+ * }</pre>
+ *
+ * Since the {@code evaluate} method does not support the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type, specifying
+ * XPathEvaluationResult as the type will result in IllegalArgumentException.
+ * Any implementation supporting the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type must override
+ * this method.
+ *
+ * @param <T> The class type that will be returned by the XPath expression.
+ * @param item The context the XPath expression will be evaluated in.
+ * @param type The class type expected to be returned by the XPath expression.
+ *
+ * @return The result of evaluating the expression.
+ *
+ * @throws XPathExpressionException If the expression cannot be evaluated.
+ * @throws IllegalArgumentException If {@code type} is not of the types
+ * corresponding to the types defined in the {@link XPathEvaluationResult.XPathResultType
+ * XPathResultType}, or XPathEvaluationResult is specified as the type but an
+ * implementation supporting the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type is not available.
+ * @throws NullPointerException If {@code type} is {@code null}.
+ *
+ * @since 1.9
+ */
+ default <T>T evaluateExpression(Object item, Class<T> type)
+ throws XPathExpressionException
+ {
+ return (T)evaluate(item, XPathEvaluationResult.XPathResultType.getQNameType(type));
+ }
+
+ /**
+ * Evaluate the compiled XPath expression in the specified context. This is
+ * equivalent to calling {@link #evaluateExpression(Object item, Class type)}
+ * with type {@link XPathEvaluationResult}:
+ * <pre> {@code
+ * evaluateExpression(item, XPathEvaluationResult.class);
+ * }</pre>
+ * <p>
+ * The parameter {@code item} represents the context the XPath expression
+ * will be operated on. The type of the context is implementation-dependent.
+ * If the value is {@code null}, the operation must have no dependency on
+ * the context, otherwise an XPathExpressionException will be thrown.
+ *
+ * @implNote
+ * The type of the context is usually {@link org.w3c.dom.Node}.
+ *
+ * @implSpec
+ * The default implementation in the XPath API is equivalent to:
+ * <pre> {@code
+ * evaluateExpression(item, XPathEvaluationResult.class);
+ * }</pre>
+ *
+ * Since the {@code evaluate} method does not support the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY}
+ * type, the default implementation of this method will always throw an
+ * IllegalArgumentException. Any implementation supporting the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type must therefore
+ * override this method.
+ *
+ * @param item The context the XPath expression will be evaluated in.
+ *
+ * @return The result of evaluating the expression.
+ *
+ * @throws XPathExpressionException If the expression cannot be evaluated.
+ * @throws IllegalArgumentException If the implementation of this method
+ * does not support the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type.
+ *
+ * @since 1.9
+ */
+ default XPathEvaluationResult<?> evaluateExpression(Object item)
+ throws XPathExpressionException
+ {
+ return evaluateExpression(item, XPathEvaluationResult.class);
+ }
+
+ /**
+ * Evaluate the compiled XPath expression in the specified context,
+ * and return the result with the type specified through the {@code class type}
+ * <p>
+ * This method builds a data model for the {@link InputSource} and calls
+ * {@link #evaluateExpression(Object item, Class type)} on the resulting
+ * document object.
+ * <P>
+ * By default, the JDK's data model is {@link org.w3c.dom.Document}.
+ *
+ * @implSpec
+ * The default implementation in the XPath API is equivalent to:
+ * <pre> {@code
+ (T)evaluate(source, XPathEvaluationResult.XPathResultType.getQNameType(type));
+ * }</pre>
+ *
+ * Since the {@code evaluate} method does not support the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type, specifying
+ * XPathEvaluationResult as the type will result in IllegalArgumentException.
+ * Any implementation supporting the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type must override
+ * this method.
+ *
+ * @param <T> The class type that will be returned by the XPath expression.
+ * @param source The {@code InputSource} of the document to evaluate over.
+ * @param type The class type expected to be returned by the XPath expression.
+ *
+ * @return The result of evaluating the expression.
+ *
+ * @throws XPathExpressionException If the expression cannot be evaluated.
+ * @throws IllegalArgumentException If {@code type} is not of the types
+ * corresponding to the types defined in the {@link XPathEvaluationResult.XPathResultType
+ * XPathResultType}, or XPathEvaluationResult is specified as the type but an
+ * implementation supporting the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type
+ * is not available.
+ * @throws NullPointerException If {@code source or type} is {@code null}.
+ *
+ * @since 1.9
+ */
+ default <T>T evaluateExpression(InputSource source, Class<T> type)
+ throws XPathExpressionException
+ {
+ return (T)evaluate(source, XPathEvaluationResult.XPathResultType.getQNameType(type));
+ }
+
+ /**
+ * Evaluate the compiled XPath expression in the specified context. This is
+ * equivalent to calling {@link #evaluateExpression(InputSource source, Class type)}
+ * with type {@link XPathEvaluationResult}:
+ * <pre> {@code
+ * evaluateExpression(source, XPathEvaluationResult.class);
+ * }</pre>
+ * <p>
+ *
+ * @implSpec
+ * The default implementation in the XPath API is equivalent to:
+ * <pre> {@code
+ * (XPathEvaluationResult)evaluateExpression(source, XPathEvaluationResult.class);
+ * }</pre>
+ *
+ * Since the {@code evaluate} method does not support the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY}
+ * type, the default implementation of this method will always throw an
+ * IllegalArgumentException. Any implementation supporting the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type must therefore
+ * override this method.
+ *
+ * @param source The {@code InputSource} of the document to evaluate over.
+ *
+ * @return The result of evaluating the expression.
+ *
+ * @throws XPathExpressionException If the expression cannot be evaluated.
+ * @throws IllegalArgumentException If the implementation of this method
+ * does not support the
+ * {@link XPathEvaluationResult.XPathResultType#ANY ANY} type.
+ * @throws NullPointerException If {@code source} is {@code null}.
+ *
+ * @since 1.9
+ */
+ default XPathEvaluationResult<?> evaluateExpression(InputSource source)
+ throws XPathExpressionException
+ {
+ return evaluateExpression(source, XPathEvaluationResult.class);
+ }
}