/* XPath.java --
   Copyright (C) 2004 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

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General Public License for more details.

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Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
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As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
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exception statement from your version. */

package javax.xml.xpath;

import javax.xml.namespace.NamespaceContext;
import javax.xml.namespace.QName;
import org.xml.sax.InputSource;

/**
 * Interface to the XPath evaluation environment.
 * @since 1.3
 */
public interface XPath
{

  /**
   * Resets the environment.
   */
  void reset();

  void setXPathVariableResolver(XPathVariableResolver resolver);

  XPathVariableResolver getXPathVariableResolver();

  void setXPathFunctionResolver(XPathFunctionResolver resolver);

  XPathFunctionResolver getXPathFunctionResolver();

  void setNamespaceContext(NamespaceContext nsContext);

  NamespaceContext getNamespaceContext();

  /**
   * Compiles an XPath expression for future evaluation.
   * @param expression the expression
   */
  XPathExpression compile(String expression)
    throws XPathExpressionException;

  /**
   * Evaluates an expression.
   * @param expression the expression
   * @param item the expression context
   * @param returnType the desired return type
   */
  Object evaluate(String expression,
                  Object item,
                  QName returnType)
    throws XPathExpressionException;

  /**
   * Evaluates an expression and returns the result as a string.
   * @param expression the expression
   * @param item the expression context
   */
  String evaluate(String expression,
                  Object item)
    throws XPathExpressionException;

  /**
   * Evaluates an expression.
   * @param expression the expression
   * @param source the source to load the expression context from
   * @param returnType the desired return type
   */
  Object evaluate(String expression,
                  InputSource source,
                  QName returnType)
    throws XPathExpressionException;

  /**
   * Evaluates an expression and returns the result as a string.
   * @param expression the expression
   * @param source the source to load the expression context from
   */
  String evaluate(String expression,
                  InputSource source)
    throws XPathExpressionException;

}