propertynode.java

抽取pdf和word文本内容的源代码

/* ====================================================================
   Copyright 2002-2004   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.
==================================================================== */
        
package org.apache.poi.hwpf.model;

import java.io.ByteArrayOutputStream;
import java.util.Arrays;

import org.apache.poi.hwpf.sprm.SprmBuffer;

/**
 * Represents a lightweight node in the Trees used to store content
 * properties.
 *
 * @author Ryan Ackley
 */
public abstract class PropertyNode implements Comparable, Cloneable
{
  protected Object _buf;
  private int _cpStart;
  private int _cpEnd;


  /**
   * @param fcStart The start of the text for this property.
   * @param fcEnd The end of the text for this property.
   * @param grpprl The property description in compressed form.
   */
  protected PropertyNode(int fcStart, int fcEnd, Object buf)
  {
      _cpStart = fcStart;
      _cpEnd = fcEnd;
      _buf = buf;

  }

  /**
   * @return The offset of this property's text.
   */
  public int getStart()
  {
      return _cpStart;
  }

  public void setStart(int start)
  {
    _cpStart = start;
  }

  /**
   * @return The offset of the end of this property's text.
   */
  public int getEnd()
  {
    return _cpEnd;
  }

  public void setEnd(int end)
  {
    _cpEnd = end;
  }

  /**
   * Adjust for a deletion that can span multiple PropertyNodes.
   * @param start
   * @param length
   */
  public void adjustForDelete(int start, int length)
  {
    int end = start + length;

    if (_cpEnd > start)
    {
      if (_cpStart < end)
      {
        _cpEnd = end >= _cpEnd ? start : _cpEnd - length;
        _cpStart = Math.min(start, _cpStart);
      }
      else
      {
        _cpEnd -= length;
        _cpStart -= length;
      }
    }
  }

  protected boolean limitsAreEqual(Object o)
  {
    return ((PropertyNode)o).getStart() == _cpStart &&
           ((PropertyNode)o).getEnd() == _cpEnd;

  }

  public boolean equals(Object o)
  {
    if (limitsAreEqual(o))
    {
      Object testBuf = ((PropertyNode)o)._buf;
      if (testBuf instanceof byte[] && _buf instanceof byte[])
      {
        return Arrays.equals((byte[])testBuf, (byte[])_buf);
      }
      return _buf.equals(testBuf);
    }
    return false;
  }

  public Object clone()
    throws CloneNotSupportedException
  {
    return super.clone();
  }

  /**
   * Used for sorting in collections.
   */
  public int compareTo(Object o)
  {
      int cpEnd = ((PropertyNode)o).getEnd();
      if(_cpEnd == cpEnd)
      {
        return 0;
      }
      else if(_cpEnd < cpEnd)
      {
        return -1;
      }
      else
      {
        return 1;
      }
  }





}