001/*
002 * Copyright 2002-2015 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 java.math.BigDecimal;
020import java.math.BigInteger;
021import java.math.RoundingMode;
022
023import org.springframework.asm.MethodVisitor;
024import org.springframework.expression.EvaluationException;
025import org.springframework.expression.Operation;
026import org.springframework.expression.TypedValue;
027import org.springframework.expression.spel.CodeFlow;
028import org.springframework.expression.spel.ExpressionState;
029import org.springframework.util.NumberUtils;
030
031/**
032 * Implements division operator.
033 *
034 * @author Andy Clement
035 * @author Juergen Hoeller
036 * @author Giovanni Dall'Oglio Risso
037 * @since 3.0
038 */
039public class OpDivide extends Operator {
040
041        public OpDivide(int pos, SpelNodeImpl... operands) {
042                super("/", pos, operands);
043        }
044
045
046        @Override
047        public TypedValue getValueInternal(ExpressionState state) throws EvaluationException {
048                Object leftOperand = getLeftOperand().getValueInternal(state).getValue();
049                Object rightOperand = getRightOperand().getValueInternal(state).getValue();
050
051                if (leftOperand instanceof Number && rightOperand instanceof Number) {
052                        Number leftNumber = (Number) leftOperand;
053                        Number rightNumber = (Number) rightOperand;
054
055                        if (leftNumber instanceof BigDecimal || rightNumber instanceof BigDecimal) {
056                                BigDecimal leftBigDecimal = NumberUtils.convertNumberToTargetClass(leftNumber, BigDecimal.class);
057                                BigDecimal rightBigDecimal = NumberUtils.convertNumberToTargetClass(rightNumber, BigDecimal.class);
058                                int scale = Math.max(leftBigDecimal.scale(), rightBigDecimal.scale());
059                                return new TypedValue(leftBigDecimal.divide(rightBigDecimal, scale, RoundingMode.HALF_EVEN));
060                        }
061                        else if (leftNumber instanceof Double || rightNumber instanceof Double) {
062                                this.exitTypeDescriptor = "D";
063                                return new TypedValue(leftNumber.doubleValue() / rightNumber.doubleValue());
064                        }
065                        else if (leftNumber instanceof Float || rightNumber instanceof Float) {
066                                this.exitTypeDescriptor = "F";
067                                return new TypedValue(leftNumber.floatValue() / rightNumber.floatValue());
068                        }
069                        else if (leftNumber instanceof BigInteger || rightNumber instanceof BigInteger) {
070                                BigInteger leftBigInteger = NumberUtils.convertNumberToTargetClass(leftNumber, BigInteger.class);
071                                BigInteger rightBigInteger = NumberUtils.convertNumberToTargetClass(rightNumber, BigInteger.class);
072                                return new TypedValue(leftBigInteger.divide(rightBigInteger));
073                        }
074                        else if (leftNumber instanceof Long || rightNumber instanceof Long) {
075                                this.exitTypeDescriptor = "J";
076                                return new TypedValue(leftNumber.longValue() / rightNumber.longValue());
077                        }
078                        else if (CodeFlow.isIntegerForNumericOp(leftNumber) || CodeFlow.isIntegerForNumericOp(rightNumber)) {
079                                this.exitTypeDescriptor = "I";
080                                return new TypedValue(leftNumber.intValue() / rightNumber.intValue());
081                        }
082                        else {
083                                // Unknown Number subtypes -> best guess is double division
084                                return new TypedValue(leftNumber.doubleValue() / rightNumber.doubleValue());
085                        }
086                }
087
088                return state.operate(Operation.DIVIDE, leftOperand, rightOperand);
089        }
090
091        @Override
092        public boolean isCompilable() {
093                if (!getLeftOperand().isCompilable()) {
094                        return false;
095                }
096                if (this.children.length > 1) {
097                         if (!getRightOperand().isCompilable()) {
098                                 return false;
099                         }
100                }
101                return (this.exitTypeDescriptor != null);
102        }
103        
104        @Override
105        public void generateCode(MethodVisitor mv, CodeFlow cf) {
106                getLeftOperand().generateCode(mv, cf);
107                String leftDesc = getLeftOperand().exitTypeDescriptor;
108                CodeFlow.insertNumericUnboxOrPrimitiveTypeCoercion(mv, leftDesc, this.exitTypeDescriptor.charAt(0));
109                if (this.children.length > 1) {
110                        cf.enterCompilationScope();
111                        getRightOperand().generateCode(mv, cf);
112                        String rightDesc = getRightOperand().exitTypeDescriptor;
113                        cf.exitCompilationScope();
114                        CodeFlow.insertNumericUnboxOrPrimitiveTypeCoercion(mv, rightDesc, this.exitTypeDescriptor.charAt(0));
115                        switch (this.exitTypeDescriptor.charAt(0)) {
116                                case 'I':
117                                        mv.visitInsn(IDIV);
118                                        break;
119                                case 'J':
120                                        mv.visitInsn(LDIV);
121                                        break;
122                                case 'F': 
123                                        mv.visitInsn(FDIV);
124                                        break;
125                                case 'D':
126                                        mv.visitInsn(DDIV);
127                                        break;                          
128                                default:
129                                        throw new IllegalStateException(
130                                                        "Unrecognized exit type descriptor: '" + this.exitTypeDescriptor + "'");
131                        }
132                }
133                cf.pushDescriptor(this.exitTypeDescriptor);
134        }
135
136}