value.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 com.caucho.quercus.QuercusException;
import com.caucho.quercus.QuercusRuntimeException;
import com.caucho.quercus.expr.Expr;
import com.caucho.quercus.program.AbstractFunction;
import com.caucho.util.L10N;
import com.caucho.vfs.WriteStream;

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.*;

/**
 * Represents a PHP expression value.
 */
abstract public class Value implements java.io.Serializable
{
  protected static final L10N L = new L10N(Value.class);

  public static final StringValue SCALAR_V = new StringBuilderValue("scalar");

  public static final Value []NULL_VALUE_ARRAY = new Value[0];
  public static final Value []NULL_ARGS = new Value[0];

  //
  // Properties
  //
  
  /**
   * Returns the value's class name.
   */
  public String getClassName()
  {
    return getType();
  }

  //
  // Predicates and Relations
  //
  
  /**
   * Returns true for an implementation of a class
   */
  public boolean isA(String name)
  {
    return false;
  }
  
  /**
   * Checks if 'this' is a valid protected call for 'className'
   */
  public void checkProtected(Env env, String className)
  {
  }
  
  /**
   * Checks if 'this' is a valid private call for 'className'
   */
  public void checkPrivate(Env env, String className)
  {
  }

  /**
   * Returns the ValueType.
   */
  public ValueType getValueType()
  {
    return ValueType.VALUE;
  }

  /**
   * Returns true for an array.
   */
  public boolean isArray()
  {
    return false;
  }

  /**
   * Returns true for a double-value.
   */
  public boolean isDoubleConvertible()
  {
    return false;
  }

  /**
   * Returns true for a long-value.
   */
  public boolean isLongConvertible()
  {
    return false;
  }

  /**
   * Returns true for a null.
   */
  public boolean isNull()
  {
    return false;
  }

  /**
   * Returns true for a number.
   */
  public boolean isNumberConvertible()
  {
    return isLongConvertible() || isDoubleConvertible();
  }

  /**
   * Matches is_numeric
   */
  public boolean isNumeric()
  {
    return false;
  }

  /**
   * Returns true for an object.
   */
  public boolean isObject()
  {
    return false;
  }
  
  /*
   * Returns true for a resource.
   */
  public boolean isResource()
  {
    return false;
  }
  
  /**
   * Returns true for a StringValue.
   */
  public boolean isString()
  {
    return false;
  }

  /**
   * Returns true for a BinaryValue.
   */
  public boolean isBinary()
  {
    return false;
  }

  /**
   * Returns true for a UnicodeValue.
   */
  public boolean isUnicode()
  {
    return false;
  }

  /**
   * Returns true for a BooleanValue
   */
  public boolean isBoolean()
  {
    return false;
  }
  
  /**
   * Returns true for a DefaultValue
   */
  public boolean isDefault()
  {
    return false;
  }

  /**
   * Returns true if the value is set.
   */
  public boolean isset()
  {
    return true;
  }

  /**
   * Returns true if the value is empty
   */
  public boolean isEmpty()
  {
    return false;
  }
  
  /**
   * Returns true if there are more elements.
   */
  public boolean hasCurrent()
  {
    return false;
  }

  /**
   * Returns true for equality
   */
  public Value eqValue(Value rValue)
  {
    return eq(rValue) ? BooleanValue.TRUE : BooleanValue.FALSE;
  }

  /**
   * Returns true for equality
   */
  public boolean eq(Value rValue)
  {
    if (rValue instanceof BooleanValue)
      return toBoolean() == rValue.toBoolean();
    else if (isLongConvertible() && rValue.isLongConvertible())
      return toLong() == rValue.toLong();
    else if (isNumberConvertible() || rValue.isNumberConvertible())
      return toDouble() == rValue.toDouble();
    else
      return toString().equals(rValue.toString());
  }

  /**
   * Returns true for equality
   */
  public boolean eql(Value rValue)
  {
    return this == rValue.toValue();
  }

  /**
   * Returns a negative/positive integer if this Value is
   * lessthan/greaterthan rValue.
   */
  public int cmp(Value rValue)
  {
    // This is tricky: implemented according to Table 15-5 of
    // http://us2.php.net/manual/en/language.operators.comparison.php
    
    Value lVal = toValue();
    Value rVal = rValue.toValue();

    if (lVal instanceof StringValue && rVal instanceof NullValue)
      return ((StringValue) lVal).cmpString(StringValue.EMPTY);

    if (lVal instanceof NullValue && rVal instanceof StringValue)
      return StringValue.EMPTY.cmpString((StringValue) rVal);

    if (lVal instanceof StringValue && rVal instanceof StringValue)
      return ((StringValue) lVal).cmpString((StringValue) rVal);

    if (lVal instanceof NullValue
        || lVal instanceof BooleanValue
        || rVal instanceof NullValue
        || rVal instanceof BooleanValue)
    {
      boolean lBool = toBoolean();
      boolean rBool    = rValue.toBoolean();

      if (!lBool && rBool) return -1;
      if (lBool && !rBool) return 1;
      return 0;
    }

    if (lVal.isObject() && rVal.isObject())
      return ((ObjectValue) lVal).cmpObject((ObjectValue) rVal);

    if ((lVal instanceof StringValue
         || lVal instanceof NumberValue
         || lVal instanceof ResourceValue)
        && (rVal instanceof StringValue
            || rVal instanceof NumberValue
            || rVal instanceof ResourceValue))
      return NumberValue.compareNum(lVal, rVal);

    if (lVal instanceof ArrayValue) return 1;
    if (rVal instanceof ArrayValue) return -1;
    if (lVal instanceof ObjectValue) return 1;
    if (rVal instanceof ObjectValue) return -1;

    // XXX: proper default case?
    throw new RuntimeException("values are incomparable: " +
			       lVal + " <=> " + rVal);
  }

  /**
   * Returns true for less than
   */
  public boolean lt(Value rValue)
  {
    return cmp(rValue) < 0;
  }

  /**
   * Returns true for less than or equal to
   */
  public boolean leq(Value rValue)
  {
    return cmp(rValue) <= 0;
  }

  /**
   * Returns true for greater than
   */
  public boolean gt(Value rValue)
  {
    return cmp(rValue) > 0;
  }

  /**
   * Returns true for greater than or equal to
   */
  public boolean geq(Value rValue)
  {
    return cmp(rValue) >= 0;
  }

  //
  // Conversions
  //

  /**
   * Converts to a boolean.
   */
  public boolean toBoolean()
  {
    return true;
  }

  /**
   * Converts to a long.
   */
  public long toLong()
  {
    return toBoolean() ? 1 : 0;
  }

  /**
   * Converts to an int
   */
  public int toInt()
  {
    return (int) toLong();
  }

  /**
   * Converts to a double.
   */
  public double toDouble()
  {
    return 0;
  }

  /**
   * Converts to a char
   */
  public char toChar()
  {
    String s = toString();

    if (s == null || s.length() < 1)
      return 0;
    else
      return s.charAt(0);
  }

  /**
   * Converts to a string.
   *
   * @param env
   */
  public StringValue toString(Env env)
  {
    return toStringValue();
  }

  /**
   * Converts to an array.
   */
  public Value toArray()
  {
    return new ArrayValueImpl().append(this);
  }

  /**
   * Converts to an array if null.
   */
  public Value toAutoArray()
  {
    return this;
  }

  /**
   * Casts to an array.
   */
  public ArrayValue toArrayValue(Env env)
  {
    env.warning(L.l("'{0}' ({1}) is not assignable to ArrayValue",
		  this, getType()));

    return null;
  }

  /**
   * Converts to an object if null.
   */
  public Value toAutoObject(Env env)
  {
    return this;
  }

  /**
   * Converts to an object.
   */
  public Value toObject(Env env)
  {
    ObjectValue obj = env.createObject();
    
    obj.putField(env, env.createString("scalar"), this);
    
    return obj;
  }

  /**
   * Converts to a java object.
   */
  public Object toJavaObject()
  {
    return null;
  }

  /**
   * Converts to a java object.
   */
  public Object toJavaObject(Env env, Class type)
  {
    env.warning(L.l("Can't convert {0} to Java {1}",
		    getClass().getName(), type.getName()));
    
    return null;
  }

  /**
   * Converts to a java object.
   */
  public Object toJavaObjectNotNull(Env env, Class type)
  {
    env.warning(L.l("Can't convert {0} to Java {1}",
		    getClass().getName(), type.getName()));
    
    return null;
  }

  /**
   * Converts to a java boolean object.
   */
  public Boolean toJavaBoolean()
  {
    return toBoolean() ? Boolean.TRUE : Boolean.FALSE;
  }

  /**
   * Converts to a java byte object.
   */
  public Byte toJavaByte()
  {
    return new Byte((byte) toLong());
  }

  /**
   * Converts to a java short object.
   */
  public Short toJavaShort()
  {
    return new Short((short) toLong());
  }

  /**
   * Converts to a java Integer object.
   */
  public Integer toJavaInteger()
  {
    return new Integer((int) toLong());
  }

  /**
   * Converts to a java Long object.
   */
  public Long toJavaLong()
  {
    return new Long((int) toLong());
  }

  /**
   * Converts to a java Float object.
   */
  public Float toJavaFloat()
  {
    return new Float((float) toDouble());
  }

  /**
   * Converts to a java Double object.
   */
  public Double toJavaDouble()
  {
    return new Double(toDouble());
  }

  /**
   * Converts to a java Character object.
   */
  public Character toJavaCharacter()
  {
    return new Character(toChar());
  }

  /**
   * Converts to a java String object.
   */
  public String toJavaString()
  {
    return toString();
  }

  /**
   * Converts to a java Collection object.
   */
  public Collection toJavaCollection(Env env, Class type)
  {
    env.warning(L.l("Can't convert {0} to Java {1}",
            getClass().getName(), type.getName()));
    
    return null;
  }
  
  /**
   * Converts to a java List object.
   */
  public List toJavaList(Env env, Class type)
  {
    env.warning(L.l("Can't convert {0} to Java {1}",
            getClass().getName(), type.getName()));
    
    return null;
  }
  
  /**
   * Converts to a java Map object.
   */
  public Map toJavaMap(Env env, Class type)
  {
    env.warning(L.l("Can't convert {0} to Java {1}",
            getClass().getName(), type.getName()));
    
    return null;
  }