/*
    * Copyright 2002-2014 the original author or authors.
    *
    * 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.springframework.expression.spel.ast;
  
  import org.springframework.asm.MethodVisitor;
  import org.springframework.expression.spel.CodeFlow;
  import org.springframework.expression.spel.support.BooleanTypedValue;
  
  /**
   * Represents the literal values TRUE and FALSE.
   *
   * @author Andy Clement
   * @since 3.0
   */
  public class BooleanLiteral extends Literal {
  
  	private final BooleanTypedValue value;
  
  
  	public BooleanLiteral(String payload, int pos, boolean value) {
  		super(payload, pos);
  		this.value = BooleanTypedValue.forValue(value);
  		this.exitTypeDescriptor = "Z";
  	}
  
  
  	@Override
  	public BooleanTypedValue getLiteralValue() {
  		return this.value;
  	}
  	
  	@Override
  	public boolean isCompilable() {
  		return true;
  	}
  	
  	@Override
  	public void generateCode(MethodVisitor mv, CodeFlow cf) {
  		if (this.value == BooleanTypedValue.TRUE) {
  			mv.visitLdcInsn(1);		
  		}
  		else {
  			mv.visitLdcInsn(0);
  		}
  		cf.pushDescriptor(this.exitTypeDescriptor);
  	}
  
  }