/*
* Copyright (c) 1998-2010 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.expr;
import com.caucho.quercus.env.BooleanValue;
import com.caucho.quercus.env.Env;
import com.caucho.quercus.env.LongValue;
import com.caucho.quercus.env.Value;
/**
* Represents a literal expression.
*/
public class LiteralExpr extends Expr {
private final Value _value;
public LiteralExpr(Value value) {
_value = value;
}
protected Value getValue() {
return _value;
}
/**
* Returns true for a literal expression.
*/
@Override
public boolean isLiteral() {
return true;
}
/**
* Returns true if a static true value.
*/
@Override
public boolean isTrue() {
if (_value == BooleanValue.TRUE) {
return true;
} else if (_value instanceof LongValue) {
return _value.toLong() != 0;
} else {
return false;
}
}
/**
* Returns true if a static true value.
*/
@Override
public boolean isFalse() {
if (_value == BooleanValue.FALSE) {
return true;
} else if (_value instanceof LongValue) {
return _value.toLong() == 0;
} else {
return false;
}
}
/**
* Returns true for a long value.
*/
@Override
public boolean isLong() {
return _value.isLongConvertible();
}
/**
* Returns true for a double value.
*/
@Override
public boolean isDouble() {
return _value.isDoubleConvertible();
}
/*
*
*/
@Override
public boolean isBoolean() {
return _value.isBoolean();
}
/**
* Evaluates the expression as a constant.
*
* @return the expression value.
*/
@Override
public Value evalConstant() {
return _value;
}
/**
* Evaluates the expression.
*
* @param env the calling environment.
*
* @return the expression value.
*/
@Override
public Value eval(Env env) {
return _value;
}
@Override
public String toString() {
return _value.toString();
}
}