attributes.java

大名鼎鼎的java动态脚本语言。已经通过了sun的认证

/*
 * Copyright 2005 John G. Wilson
 *
 * 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.
 *
 */

package groovy.util.slurpersupport;

import groovy.lang.Closure;
import groovy.lang.GroovyObject;
import groovy.lang.GroovyRuntimeException;

import java.io.IOException;
import java.io.Writer;
import java.util.Iterator;
import java.util.Map;

/**
 * @author John Wilson
 *
 */

class Attributes extends NodeChildren {
  final String attributeName;
  
  public Attributes(final GPathResult parent, final String name, final String namespacePrefix, final Map namespaceTagHints) {
    super(parent, name, namespacePrefix, namespaceTagHints);
    
    this.attributeName = this.name.substring(1);
  }
  
  public Attributes(final GPathResult parent, final String name, final Map namespaceTagHints) {
    this(parent, name, "*", namespaceTagHints);
  }
  
  /* (non-Javadoc)
   * @see org.codehaus.groovy.sandbox.util.slurpersupport.NodeChildren#childNodes()
   */
  public Iterator childNodes() {
    throw new GroovyRuntimeException("Can't get the child nodes on a a GPath expression selecting attributes: ...." + this.parent.name() + "." + name() + ".childNodes()");
  }
  
  /* (non-Javadoc)
   * @see org.codehaus.groovy.sandbox.util.slurpersupport.NodeChildren#iterator()
   */
  public Iterator iterator() {
    return new NodeIterator(this.parent.nodeIterator()) {
                  /* (non-Javadoc)
                   * @see org.codehaus.groovy.sandbox.util.slurpersupport.NodeIterator#getNextNode(java.util.Iterator)
                   */
                  protected Object getNextNode(final Iterator iter) {
                    while (iter.hasNext()) {
                      final Object value = ((Node)iter.next()).attributes().get(Attributes.this.attributeName);
                      
                        if (value != null) {
                          return value;
                        }
                    }
                    
                    return null;
                  }
                };
  }
  
  /* (non-Javadoc)
   * @see org.codehaus.groovy.sandbox.util.slurpersupport.NodeChildren#parents()
   */
  public GPathResult parents() {
    return super.parents();
  }
  
  /* (non-Javadoc)
   * @see org.codehaus.groovy.sandbox.util.slurpersupport.NodeChildren#text()
   */
  public String text() {
  final StringBuffer buf = new StringBuffer();
  final Iterator iter = iterator();

    while (iter.hasNext()) {
      buf.append(iter.next());
    }
    
    return buf.toString();
  }
  
  /* (non-Javadoc)
   * @see org.codehaus.groovy.sandbox.util.slurpersupport.NodeChildren#find(groovy.lang.Closure)
   */
  public GPathResult find(final Closure closure) {
    return new FilteredAttributes(this, closure, this.namespaceTagHints);
  }

  /* (non-Javadoc)
   * @see org.codehaus.groovy.sandbox.util.slurpersupport.NodeChildren#writeTo(java.io.Writer)
   */
  public Writer writeTo(final Writer out) throws IOException {
    out.write(text());
    
    return out;
  }
  
  /* (non-Javadoc)
   * @see org.codehaus.groovy.sandbox.util.slurpersupport.NodeChildren#build(groovy.lang.GroovyObject)
   */
  public void build(final GroovyObject builder) {
    builder.getProperty("mkp");
    builder.invokeMethod("yield", new Object[]{text()});
  }
}