nodetest.java

java1.6众多例子参考

/*
 * Copyright 1999-2004 The Apache Software Foundation.
 *
 * 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: NodeTest.java,v 1.2.4.2 2005/09/15 00:21:14 jeffsuttor Exp $
 */
package com.sun.org.apache.xpath.internal.patterns;

import com.sun.org.apache.xml.internal.dtm.DTM;
import com.sun.org.apache.xml.internal.dtm.DTMFilter;
import com.sun.org.apache.xpath.internal.Expression;
import com.sun.org.apache.xpath.internal.ExpressionOwner;
import com.sun.org.apache.xpath.internal.XPath;
import com.sun.org.apache.xpath.internal.XPathContext;
import com.sun.org.apache.xpath.internal.XPathVisitor;
import com.sun.org.apache.xpath.internal.objects.XNumber;
import com.sun.org.apache.xpath.internal.objects.XObject;

/**
 * This is the basic node test class for both match patterns and location path
 * steps.
 * @xsl.usage advanced
 */
public class NodeTest extends Expression
{
    static final long serialVersionUID = -5736721866747906182L;

  /**
   * The namespace or local name for node tests with a wildcard.
   *  @see <a href="http://www.w3.org/TR/xpath#NT-NameTest">the XPath NameTest production.</a> 
   */
  public static final String WILD = "*";

  /**
   * The URL to pass to the Node#supports method, to see if the
   * DOM has already been stripped of whitespace nodes. 
   */
  public static final String SUPPORTS_PRE_STRIPPING =
    "http://xml.apache.org/xpath/features/whitespace-pre-stripping";

  /**
   * This attribute determines which node types are accepted.
   * @serial
   */
  protected int m_whatToShow;

  /**
   * Special bitmap for match patterns starting with a function.
   * Make sure this does not conflict with {@link org.w3c.dom.traversal.NodeFilter}.
   */
  public static final int SHOW_BYFUNCTION = 0x00010000;

  /**
   * This attribute determines which node types are accepted.
   * These constants are defined in the {@link org.w3c.dom.traversal.NodeFilter}
   * interface.
   *
   * @return bitset mainly defined in {@link org.w3c.dom.traversal.NodeFilter}.
   */
  public int getWhatToShow()
  {
    return m_whatToShow;
  }
  
  /**
   * This attribute determines which node types are accepted.
   * These constants are defined in the {@link org.w3c.dom.traversal.NodeFilter}
   * interface.
   *
   * @param what bitset mainly defined in {@link org.w3c.dom.traversal.NodeFilter}.
   */
  public void setWhatToShow(int what)
  {
    m_whatToShow = what;
  }

  /**
   * The namespace to be tested for, which may be null.
   *  @serial 
   */
  String m_namespace;

  /**
   * Return the namespace to be tested.
   *
   * @return The namespace to be tested for, or {@link #WILD}, or null.
   */
  public String getNamespace()
  {
    return m_namespace;
  }

  /**
   * Set the namespace to be tested.
   *
   * @param ns The namespace to be tested for, or {@link #WILD}, or null.
   */
  public void setNamespace(String ns)
  {
    m_namespace = ns;
  }

  /**
   * The local name to be tested for.
   *  @serial 
   */
  protected String m_name;

  /**
   * Return the local name to be tested.
   *
   * @return the local name to be tested, or {@link #WILD}, or an empty string.
   */
  public String getLocalName()
  {
    return (null == m_name) ? "" : m_name;
  }

  /**
   * Set the local name to be tested.
   *
   * @param name the local name to be tested, or {@link #WILD}, or an empty string.
   */
  public void setLocalName(String name)
  {
    m_name = name;
  }

  /**
   * Statically calculated score for this test.  One of
   *  {@link #SCORE_NODETEST},
   *  {@link #SCORE_NONE},
   *  {@link #SCORE_NSWILD},
   *  {@link #SCORE_QNAME}, or
   *  {@link #SCORE_OTHER}.
   *  @serial
   */
  XNumber m_score;

  /**
   * The match score if the pattern consists of just a NodeTest.
   *  @see <a href="http://www.w3.org/TR/xslt#conflict">XSLT Specification - 5.5 Conflict Resolution for Template Rules</a> 
   */
  public static final XNumber SCORE_NODETEST =
    new XNumber(XPath.MATCH_SCORE_NODETEST);

  /**
   * The match score if the pattern pattern has the form NCName:*.
   *  @see <a href="http://www.w3.org/TR/xslt#conflict">XSLT Specification - 5.5 Conflict Resolution for Template Rules</a> 
   */
  public static final XNumber SCORE_NSWILD =
    new XNumber(XPath.MATCH_SCORE_NSWILD);

  /**
   * The match score if the pattern has the form
   * of a QName optionally preceded by an @ character.
   *  @see <a href="http://www.w3.org/TR/xslt#conflict">XSLT Specification - 5.5 Conflict Resolution for Template Rules</a> 
   */
  public static final XNumber SCORE_QNAME =
    new XNumber(XPath.MATCH_SCORE_QNAME);

  /**
   * The match score if the pattern consists of something
   * other than just a NodeTest or just a qname.
   *  @see <a href="http://www.w3.org/TR/xslt#conflict">XSLT Specification - 5.5 Conflict Resolution for Template Rules</a> 
   */
  public static final XNumber SCORE_OTHER =
    new XNumber(XPath.MATCH_SCORE_OTHER);

  /**
   * The match score if no match is made.
   *  @see <a href="http://www.w3.org/TR/xslt#conflict">XSLT Specification - 5.5 Conflict Resolution for Template Rules</a> 
   */
  public static final XNumber SCORE_NONE =
    new XNumber(XPath.MATCH_SCORE_NONE);

  /**
   * Construct an NodeTest that tests for namespaces and node names.
   *
   *
   * @param whatToShow Bit set defined mainly by {@link org.w3c.dom.traversal.NodeFilter}.
   * @param namespace The namespace to be tested.
   * @param name The local name to be tested.
   */
  public NodeTest(int whatToShow, String namespace, String name)
  {
    initNodeTest(whatToShow, namespace, name);
  }

  /**
   * Construct an NodeTest that doesn't test for node names.
   *
   *
   * @param whatToShow Bit set defined mainly by {@link org.w3c.dom.traversal.NodeFilter}.
   */
  public NodeTest(int whatToShow)
  {
    initNodeTest(whatToShow);
  }
  
  /**
   * @see Expression#deepEquals(Expression)
   */
  public boolean deepEquals(Expression expr)
  {
  	if(!isSameClass(expr))
  		return false;
  		
  	NodeTest nt = (NodeTest)expr;

  	if(null != nt.m_name)
  	{
  		if(null == m_name)
  			return false;
  		else if(!nt.m_name.equals(m_name))
  			return false;
  	}
  	else if(null != m_name)
  		return false;

  	if(null != nt.m_namespace)
  	{
  		if(null == m_namespace)
  			return false;
  		else if(!nt.m_namespace.equals(m_namespace))
  			return false;
  	}
  	else if(null != m_namespace)
  		return false;
  		  		
  	if(m_whatToShow != nt.m_whatToShow)
  		return false;
  		
  	if(m_isTotallyWild != nt.m_isTotallyWild)
  		return false;

	return true;
  }

  /**
   * Null argument constructor.
   */
  public NodeTest(){}

  /**
   * Initialize this node test by setting the whatToShow property, and
   * calculating the score that this test will return if a test succeeds.
   *
   *
   * @param whatToShow Bit set defined mainly by {@link org.w3c.dom.traversal.NodeFilter}.
   */
  public void initNodeTest(int whatToShow)
  {

    m_whatToShow = whatToShow;

    calcScore();
  }

  /**
   * Initialize this node test by setting the whatToShow property and the
   * namespace and local name, and
   * calculating the score that this test will return if a test succeeds.
   *
   *
   * @param whatToShow Bit set defined mainly by {@link org.w3c.dom.traversal.NodeFilter}.
   * @param namespace The namespace to be tested.
   * @param name The local name to be tested.
   */
  public void initNodeTest(int whatToShow, String namespace, String name)
  {

    m_whatToShow = whatToShow;
    m_namespace = namespace;
    m_name = name;

    calcScore();
  }

  /**
   * True if this test has a null namespace and a local name of {@link #WILD}.
   *  @serial 
   */
  private boolean m_isTotallyWild;
  
  /**
   * Get the static score for this node test.
   * @return Should be one of the SCORE_XXX constants.
   */
  public XNumber getStaticScore()
  {
    return m_score;
  }
  
  /**
   * Set the static score for this node test.
   * @param score Should be one of the SCORE_XXX constants.
   */
  public void setStaticScore(XNumber score)
  {
    m_score = score;
  }

  /**
   * Static calc of match score.
   */
  protected void calcScore()
  {

    if ((m_namespace == null) && (m_name == null))
      m_score = SCORE_NODETEST;
    else if (((m_namespace == WILD) || (m_namespace == null))
             && (m_name == WILD))
      m_score = SCORE_NODETEST;
    else if ((m_namespace != WILD) && (m_name == WILD))
      m_score = SCORE_NSWILD;
    else
      m_score = SCORE_QNAME;

    m_isTotallyWild = (m_namespace == null && m_name == WILD);
  }

  /**
   * Get the score that this test will return if a test succeeds.
   *
   *
   * @return the score that this test will return if a test succeeds.
   */
  public double getDefaultScore()
  {
    return m_score.num();
  }
  
  /**