/*
* Copyright (c) 1998-2011 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.IOException;
import java.io.PrintWriter;
/**
* Represents a PHP default value.
*/
@SuppressWarnings("serial")
public class DefaultValue extends NullValue {
public static final DefaultValue DEFAULT
= new DefaultValue();
private DefaultValue()
{
}
/**
* Returns the null value singleton.
*/
public static DefaultValue create()
{
return DEFAULT;
}
/**
* Returns true for a DefaultValue
*/
@Override
public boolean isDefault()
{
return true;
}
/**
* Converts to a boolean.
*/
@Override
public boolean toBoolean()
{
return false;
}
/**
* Converts to a long.
*/
@Override
public long toLong()
{
return 0;
}
/**
* Converts to a double.
*/
@Override
public double toDouble()
{
return 0;
}
/**
* Converts to an object.
*/
public Object toObject()
{
return "";
}
/**
* Converts to a callable
*/
@Override
public Callable toCallable(Env env)
{
return null;
}
/**
* Prints the value.
* @param env
*/
@Override
public void print(Env env)
{
}
/**
* Converts to a string.
* @param env
*/
@Override
public String toString()
{
return "";
}
/**
* Generates code to recreate the expression.
*
* @param out the writer to the Java source code.
*/
@Override
public void generate(PrintWriter out)
throws IOException
{
out.print("DefaultValue.DEFAULT");
}
/**
* Generates code to recreate the expression.
*
* @param out the writer to the Java source code.
*/
public void generateLong(PrintWriter out)
throws IOException
{
out.print("0");
}
/**
* Generates code to recreate the expression.
*
* @param out the writer to the Java source code.
*/
public void generateString(PrintWriter out)
throws IOException
{
out.print("\"\"");
}
//
// Java Serialization
//
private Object readResolve()
{
return DEFAULT;
}
}