001/*
002 * Copyright 2002-2019 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.expression.spel.ast;
018
019import org.springframework.asm.MethodVisitor;
020import org.springframework.expression.TypedValue;
021import org.springframework.expression.spel.CodeFlow;
022import org.springframework.util.Assert;
023
024/**
025 * Expression language AST node that represents an integer literal.
026 *
027 * @author Andy Clement
028 * @since 3.0
029 */
030public class IntLiteral extends Literal {
031
032        private final TypedValue value;
033
034
035        public IntLiteral(String payload, int startPos, int endPos, int value) {
036                super(payload, startPos, endPos);
037                this.value = new TypedValue(value);
038                this.exitTypeDescriptor = "I";
039        }
040
041
042        @Override
043        public TypedValue getLiteralValue() {
044                return this.value;
045        }
046
047        @Override
048        public boolean isCompilable() {
049                return true;
050        }
051
052        @Override
053        public void generateCode(MethodVisitor mv, CodeFlow cf) {
054                Integer intValue = (Integer) this.value.getValue();
055                Assert.state(intValue != null, "No int value");
056                if (intValue == -1) {
057                        // Not sure we can get here because -1 is OpMinus
058                        mv.visitInsn(ICONST_M1);
059                }
060                else if (intValue >= 0 && intValue < 6) {
061                        mv.visitInsn(ICONST_0 + intValue);
062                }
063                else {
064                        mv.visitLdcInsn(intValue);
065                }
066                cf.pushDescriptor(this.exitTypeDescriptor);
067        }
068
069}