src/java.xml/share/classes/javax/xml/xpath/XPathExpression.java

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*** 1,7 **** /* ! * Copyright (c) 2003, 2005, 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 --- 1,7 ---- /* ! * 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
*** 23,37 **** * questions. */ package javax.xml.xpath; - import org.xml.sax.InputSource; import javax.xml.namespace.QName; /** ! * <p><code>XPathExpression</code> provides access to compiled XPath expressions.</p> * * <a name="XPathExpression-evaluation"/> * <table border="1" cellpadding="2"> * <thead> * <tr> --- 23,37 ---- * questions. */ package javax.xml.xpath; import javax.xml.namespace.QName; + import org.xml.sax.InputSource; /** ! * <p>{@code XPathExpression} provides access to compiled XPath expressions.</p> * * <a name="XPathExpression-evaluation"/> * <table border="1" cellpadding="2"> * <thead> * <tr>
*** 51,70 **** * <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 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> * </td> * </tr> * <tr> * <td>QNames</td> * <td> --- 51,70 ---- * <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} 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} for the function.</p> * </td> * </tr> * <tr> * <td>QNames</td> * <td>
*** 82,200 **** * </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> * method is invoked, applications may not recursively call ! * the <code>evaluate</code> 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> * @since 1.5 */ public interface XPathExpression { /** * <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>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 (a node, 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>. */ 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>This method calls {@link #evaluate(Object item, QName returnType)} with a <code>returnType</code> 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. * ! * @param item The starting context (a node, 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. */ 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 * 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>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>. */ 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>This method calls {@link #evaluate(InputSource source, QName returnType)} with a <code>returnType</code> 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> * ! * @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>. */ public String evaluate(InputSource source) throws XPathExpressionException; } --- 82,386 ---- * </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} * method is invoked, applications may not recursively call ! * 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> * @since 1.5 */ public interface XPathExpression { + /** * <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> ! * 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}. * ! * @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} 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} 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}.</p> * ! * <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> ! * 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}. * ! * @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} 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} is not one of the types defined in {@link XPathConstants}, ! * then an {@code IllegalArgumentException} 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} of the document to evaluate over. * @param returnType The desired return type. * ! * @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} 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} and return the result as a ! * {@code String}.</p> * ! * <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} is {@code null}, then a {@code NullPointerException} is thrown.</p> * ! * @param source The {@code InputSource} of the document to evaluate over. * ! * @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} 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 type.cast(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 type.cast(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); + } }