largestringbuildervalue.java

RESIN 3.2 最新源码

/*
 * Copyright (c) 1998-2008 Caucho Technology -- all rights reserved
 *
 * This file is part of Resin(R) Open Source
 *
 * Each copy or derived work must preserve the copyright notice and this
 * notice unmodified.
 *
 * Resin Open Source 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 of the License, or
 * (at your option) any later version.
 *
 * Resin Open Source is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, or any warranty
 * of NON-INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Resin Open Source; if not, write to the
 *
 *   Free Software Foundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.quercus.env;

import java.io.*;
import java.util.*;

import com.caucho.vfs.*;
import com.caucho.quercus.QuercusRuntimeException;
import com.caucho.util.*;

/**
 * Represents a 8-bit PHP 5 style binary builder (unicode.semantics = off),
 * used for large data like file reads.
 */
public class LargeStringBuilderValue
  extends StringValue
{
  public static final int SIZE = 4 * 1024;
  
  protected byte [][]_bufferList;
  protected int _length;

  private int _hashCode;
  private String _value;

  public LargeStringBuilderValue()
  {
    _bufferList = new byte[32][];
    _bufferList[0] = new byte[SIZE];
  }

  public LargeStringBuilderValue(byte [][]bufferList, int length)
  {
    _bufferList = bufferList;
    _length = length;
  }
  
  /*
   * Creates an empty string builder of the same type.
   */
  public StringValue createEmptyStringBuilder()
  {
    return new StringBuilderValue();
  }
  
  /*
   * Returns the empty string of same type.
   */
  public StringValue getEmptyString()
  {
    return StringBuilderValue.EMPTY;
  }

  /**
   * Returns the value.
   */
  public String getValue()
  {
    return toString();
  }

  /**
   * Returns the type.
   */
  @Override
  public String getType()
  {
    return "string";
  }

  /**
   * Returns the ValueType.
   */
  @Override
  public ValueType getValueType()
  {
    return BinaryBuilderValue.getValueType(_bufferList[0], 0, _length);
  }

  /**
   * Returns true for a long
   */
  @Override
  public boolean isLongConvertible()
  {
    return false;
  }

  /**
   * Returns true for a double
   */
  public boolean isDouble()
  {
    return false;
  }

  /**
   * Returns true for a number
   */
  @Override
  public boolean isNumber()
  {
    return false;
  }

  /**
   * Returns true for a scalar
   */
  @Override
  public boolean isScalar()
  {
    return true;
  }

  /**
   * Converts to a boolean.
   */
  @Override
  public boolean toBoolean()
  {
    if (_length == 0)
      return false;
    else if (_length == 1 && _bufferList[0][0] == '0')
      return false;
    else
      return true;
  }

  /**
   * Converts to a long.
   */
  @Override
  public long toLong()
  {
    return parseLong(_bufferList[0], 0, _length);
  }

  /**
   * Converts to a double.
   */
  @Override
  public double toDouble()
  {
    return BinaryBuilderValue.toDouble(_bufferList[0], 0, _length);
  }

  /**
   * Convert to an input stream.
   */
  @Override
  public InputStream toInputStream()
  {
    return new BuilderInputStream();
  }

  /**
   * Converts to a string.
   */
  @Override
  public String toString()
  {
    char []buffer = new char[_length];

    byte [][]bufferList = _bufferList;
    for (int i = _length - 1; i >= 0; i--) {
      buffer[i] = (char) bufferList[i / SIZE][i % SIZE];
    }

    return new String(buffer, 0, _length);
  }

  /**
   * Converts to an object.
   */
  @Override
  public Object toJavaObject()
  {
    return toString();
  }

  /**
   * Converts to a string builder
   */
  @Override
  public StringValue toStringBuilder()
  {
    // XXX: can this just return this, or does it need to return a copy?
    
    return new LargeStringBuilderValue(_bufferList, _length);
  }

  /**
   * Converts to a BinaryValue.
   */
  @Override
  public StringValue toBinaryValue(Env env)
  {
    return this;
  }

  /**
   * Converts to a BinaryValue in desired charset.
   */
  @Override
  public StringValue toBinaryValue(Env env, String charset)
  {
    return this;
  }
  
  /**
   * Append to a string builder.
   */
  public void appendTo(StringValue bb)
  {
    int tail = _length % SIZE;
    int fixedLength = (_length - tail) / SIZE;

    int i = 0;
    for (; i < fixedLength; i++) {
      bb.append(_bufferList[i], 0, SIZE);
    }

    bb.append(_bufferList[i], 0, tail);
  }

  /**
   * Converts to a key.
   */
  @Override
  public Value toKey()
  {
    if (getValueType().isLongAdd())
      return LongValue.create(toLong());
    else
      return this;
  }

  /**
   * Converts to a byte array, with no consideration of character encoding.
   * Each character becomes one byte, characters with values above 255 are
   * not correctly preserved.
   */
  public byte[] toBytes()
  {
    byte[] bytes = new byte[_length];

    byte [][]bufferList = _bufferList;
    for (int i = _length - 1; i >= 0; i--) {
      bytes[i] = bufferList[i / SIZE][i % SIZE];
    }

    return bytes;
  }

  //
  // Operations
  //

  /**
   * Returns the character at an index
   */
  public Value get(Value key)
  {
    return charValueAt(key.toLong());
  }

  /**
   * Returns the character at an index
   */
  public Value getRef(Value key)
  {
    return charValueAt(key.toLong());
  }

  /**
   * Returns the character at an index
   */
  @Override
  public Value charValueAt(long index)
  {
    int len = _length;

    if (index < 0 || len <= index)
      return UnsetStringValue.UNSET;
    else {
      int data = _bufferList[(int) (index / SIZE)][(int) (index % SIZE)];
      
      return StringBuilderValue.create((char) (data & 0xff));
    }
  }

  //
  // CharSequence
  //

  /**
   * Returns the length of the string.
   */
  @Override
  public int length()
  {
    return _length;
  }

  /**
   * Returns the character at a particular location
   */
  @Override
  public char charAt(int index)
  {
    int data = _bufferList[index / SIZE][index % SIZE] & 0xff;
    
    return (char) data;
  }

  /**
   * Returns a subsequence
   */
  @Override
  public CharSequence subSequence(int start, int end)
  {
    if (end <= start)
      return StringBuilderValue.EMPTY;

    StringValue stringValue;
    
    if (end - start < 1024)
      stringValue = new StringBuilderValue(end - start);
    else
      stringValue = new LargeStringBuilderValue();

    int endChunk = end / SIZE;
      
    while (start < end) {
      int startChunk = start / SIZE;
      int startOffset = start % SIZE;

      if (startChunk == endChunk) {
	stringValue.append(_bufferList[startChunk],
			   startOffset,
			   (end - start));
	  
	return stringValue;
      }
      else {
	int len = SIZE - startOffset;

	stringValue.append(_bufferList[startChunk], startOffset, len);

	start += len;
      }
    }

    return stringValue;
  }

  /**
   * Convert to lower case.
   */
  @Override
  public StringValue toLowerCase()
  {
    int length = _length;
    
    StringValue string = new LargeStringBuilderValue();

    byte [][]bufferList = _bufferList;

    for (int i = 0; i < length; i++) {
      int ch = bufferList[i / SIZE][i % SIZE] & 0xff;

      if ('A' <= ch && ch <= 'Z')
	ch = (ch + 'a' - 'A');

      string.append((char) ch);
    }

    return string;
  }
  
  /**
   * Convert to lower case.
   */
  @Override
  public StringValue toUpperCase()
  {
    int length = _length;
    
    StringValue string = new LargeStringBuilderValue();

    byte [][]bufferList = _bufferList;

    for (int i = 0; i < length; i++) {
      int ch = bufferList[i / SIZE][i % SIZE] & 0xff;

      if ('a' <= ch && ch <= 'z')
	ch = (ch + 'A' - 'a');

      string.append((char) ch);
    }

    return string;
  }

  //
  // append code
  //

  /**
   * Creates a string builder of the same type.
   */
  @Override
  public StringValue createStringBuilder()
  {
    return new StringBuilderValue();
  }

  /**
   * Creates a string builder of the same type.
   */
  @Override
  public StringValue createStringBuilder(int length)
  {
    return new StringBuilderValue(length);
  }

  /**
   * Converts to a string builder
   */
  @Override
  public StringValue toStringBuilder(Env env)
  {
    return new LargeStringBuilderValue(_bufferList, _length);
  }

  /**
   * Append a Java buffer to the value.
   */
  @Override