Source for gnu.xml.xpath.XPathImpl

   1: /* XPathImpl.java --
   2:    Copyright (C) 2004 Free Software Foundation, Inc.
   3: 
   4: This file is part of GNU Classpath.
   5: 
   6: GNU Classpath is free software; you can redistribute it and/or modify
   7: it under the terms of the GNU General Public License as published by
   8: the Free Software Foundation; either version 2, or (at your option)
   9: any later version.
  10: 
  11: GNU Classpath is distributed in the hope that it will be useful, but
  12: WITHOUT ANY WARRANTY; without even the implied warranty of
  13: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14: General Public License for more details.
  15: 
  16: You should have received a copy of the GNU General Public License
  17: along with GNU Classpath; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 USA.
  20: 
  21: Linking this library statically or dynamically with other modules is
  22: making a combined work based on this library.  Thus, the terms and
  23: conditions of the GNU General Public License cover the whole
  24: combination.
  25: 
  26: As a special exception, the copyright holders of this library give you
  27: permission to link this library with independent modules to produce an
  28: executable, regardless of the license terms of these independent
  29: modules, and to copy and distribute the resulting executable under
  30: terms of your choice, provided that you also meet, for each linked
  31: independent module, the terms and conditions of the license of that
  32: module.  An independent module is a module which is not derived from
  33: or based on this library.  If you modify this library, you may extend
  34: this exception to your version of the library, but you are not
  35: obligated to do so.  If you do not wish to do so, delete this
  36: exception statement from your version. */
  37: 
  38: package gnu.xml.xpath;
  39: 
  40: import java.io.IOException;
  41: import javax.xml.namespace.NamespaceContext;
  42: import javax.xml.namespace.QName;
  43: import javax.xml.xpath.XPath;
  44: import javax.xml.xpath.XPathExpression;
  45: import javax.xml.xpath.XPathExpressionException;
  46: import javax.xml.xpath.XPathFunctionResolver;
  47: import javax.xml.xpath.XPathVariableResolver;
  48: import org.xml.sax.InputSource;
  49: 
  50: /**
  51:  * JAXP XPath implementation.
  52:  *
  53:  * @author <a href='mailto:dog@gnu.org'>Chris Burdess</a>
  54:  */
  55: public class XPathImpl
  56:   implements XPath
  57: {
  58: 
  59:   XPathParser parser;
  60:   NamespaceContext namespaceContext;
  61:   XPathVariableResolver variableResolver;
  62:   XPathFunctionResolver functionResolver;
  63: 
  64:   XPathImpl(NamespaceContext namespaceContext,
  65:             XPathVariableResolver variableResolver,
  66:             XPathFunctionResolver functionResolver)
  67:   {
  68:     parser = new XPathParser();
  69:     this.namespaceContext = namespaceContext;
  70:     this.variableResolver = variableResolver;
  71:     this.functionResolver = functionResolver;
  72:     reset();
  73:   }
  74: 
  75:   public void reset()
  76:   {
  77:     parser.namespaceContext = namespaceContext;
  78:     parser.variableResolver = variableResolver;
  79:     parser.functionResolver = functionResolver;
  80:   }
  81: 
  82:   public void setXPathVariableResolver(XPathVariableResolver resolver)
  83:   {
  84:     parser.variableResolver = resolver;
  85:   }
  86: 
  87:   public XPathVariableResolver getXPathVariableResolver()
  88:   {
  89:     return parser.variableResolver;
  90:   }
  91: 
  92:   public void setXPathFunctionResolver(XPathFunctionResolver resolver)
  93:   {
  94:     parser.functionResolver = resolver;
  95:   }
  96: 
  97:   public XPathFunctionResolver getXPathFunctionResolver()
  98:   {
  99:     return parser.functionResolver;
 100:   }
 101: 
 102:   public void setNamespaceContext(NamespaceContext nsContext)
 103:   {
 104:     parser.namespaceContext = nsContext;
 105:   }
 106: 
 107:   public NamespaceContext getNamespaceContext()
 108:   {
 109:     return parser.namespaceContext;
 110:   }
 111: 
 112:   public XPathExpression compile(String expression)
 113:     throws XPathExpressionException
 114:   {
 115:     XPathTokenizer tokenizer = new XPathTokenizer(expression);
 116:     try
 117:       {
 118:         return (Expr) parser.yyparse(tokenizer);
 119:       }
 120:     catch (IOException e)
 121:       {
 122:         throw new XPathExpressionException(e);
 123:       }
 124:     catch (XPathParser.yyException e)
 125:       {
 126:         throw new XPathExpressionException(expression);
 127:       }
 128:   }
 129: 
 130:   public Object evaluate(String expression,
 131:                          Object item,
 132:                          QName returnType)
 133:     throws XPathExpressionException
 134:   {
 135:     XPathExpression expr = compile(expression);
 136:     return expr.evaluate(item, returnType);
 137:   }
 138: 
 139:   public String evaluate(String expression,
 140:                          Object item)
 141:     throws XPathExpressionException
 142:   {
 143:     XPathExpression expr = compile(expression);
 144:     return expr.evaluate(item);
 145:   }
 146: 
 147:   public Object evaluate(String expression,
 148:                          InputSource source,
 149:                          QName returnType)
 150:     throws XPathExpressionException
 151:   {
 152:     XPathExpression expr = compile(expression);
 153:     return expr.evaluate(source, returnType);
 154:   }
 155: 
 156:   public String evaluate(String expression,
 157:                          InputSource source)
 158:     throws XPathExpressionException
 159:   {
 160:     XPathExpression expr = compile(expression);
 161:     return expr.evaluate(source);
 162:   }
 163: 
 164: }