1 /* 2 * ProGuard -- shrinking, optimization, obfuscation, and preverification 3 * of Java bytecode. 4 * 5 * Copyright (c) 2002-2014 Eric Lafortune (eric (at) graphics.cornell.edu) 6 * 7 * This program is free software; you can redistribute it and/or modify it 8 * under the terms of the GNU General Public License as published by the Free 9 * Software Foundation; either version 2 of the License, or (at your option) 10 * any later version. 11 * 12 * This program is distributed in the hope that it will be useful, but WITHOUT 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 15 * more details. 16 * 17 * You should have received a copy of the GNU General Public License along 18 * with this program; if not, write to the Free Software Foundation, Inc., 19 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 20 */ 21 package proguard.evaluation.value; 22 23 import proguard.classfile.*; 24 25 /** 26 * This value factory creates particular values. 27 * 28 * @author Eric Lafortune 29 */ 30 public class ParticularValueFactory 31 extends ValueFactory 32 { 33 // Shared copies of Value objects, to avoid creating a lot of objects. 34 static final IntegerValue INTEGER_VALUE_M1 = new ParticularIntegerValue(-1); 35 static final IntegerValue INTEGER_VALUE_0 = new ParticularIntegerValue(0); 36 static final IntegerValue INTEGER_VALUE_1 = new ParticularIntegerValue(1); 37 static final IntegerValue INTEGER_VALUE_2 = new ParticularIntegerValue(2); 38 static final IntegerValue INTEGER_VALUE_3 = new ParticularIntegerValue(3); 39 static final IntegerValue INTEGER_VALUE_4 = new ParticularIntegerValue(4); 40 static final IntegerValue INTEGER_VALUE_5 = new ParticularIntegerValue(5); 41 static final LongValue LONG_VALUE_0 = new ParticularLongValue(0); 42 static final LongValue LONG_VALUE_1 = new ParticularLongValue(1); 43 static final FloatValue FLOAT_VALUE_0 = new ParticularFloatValue(0.0f); 44 static final FloatValue FLOAT_VALUE_1 = new ParticularFloatValue(1.0f); 45 static final FloatValue FLOAT_VALUE_2 = new ParticularFloatValue(2.0f); 46 static final DoubleValue DOUBLE_VALUE_0 = new ParticularDoubleValue(0.0); 47 static final DoubleValue DOUBLE_VALUE_1 = new ParticularDoubleValue(1.0); 48 49 50 private static int POS_ZERO_FLOAT_BITS = Float.floatToIntBits(0.0f); 51 private static long POS_ZERO_DOUBLE_BITS = Double.doubleToLongBits(0.0); 52 53 54 // Implementations for ValueFactory. 55 56 public IntegerValue createIntegerValue(int value) 57 { 58 switch (value) 59 { 60 case -1: return INTEGER_VALUE_M1; 61 case 0: return INTEGER_VALUE_0; 62 case 1: return INTEGER_VALUE_1; 63 case 2: return INTEGER_VALUE_2; 64 case 3: return INTEGER_VALUE_3; 65 case 4: return INTEGER_VALUE_4; 66 case 5: return INTEGER_VALUE_5; 67 default: return new ParticularIntegerValue(value); 68 } 69 } 70 71 72 public LongValue createLongValue(long value) 73 { 74 return value == 0L ? LONG_VALUE_0 : 75 value == 1L ? LONG_VALUE_1 : 76 new ParticularLongValue(value); 77 } 78 79 80 public FloatValue createFloatValue(float value) 81 { 82 // Make sure to distinguish between +0.0 and -0.0. 83 return value == 0.0f && Float.floatToIntBits(value) == POS_ZERO_FLOAT_BITS 84 ? FLOAT_VALUE_0 : 85 value == 1.0f ? FLOAT_VALUE_1 : 86 value == 2.0f ? FLOAT_VALUE_2 : 87 new ParticularFloatValue(value); 88 } 89 90 91 public DoubleValue createDoubleValue(double value) 92 { 93 // Make sure to distinguish between +0.0 and -0.0. 94 return value == 0.0 && Double.doubleToLongBits(value) == POS_ZERO_DOUBLE_BITS 95 ? DOUBLE_VALUE_0 : 96 value == 1.0 ? DOUBLE_VALUE_1 : 97 new ParticularDoubleValue(value); 98 } 99 100 101 public ReferenceValue createArrayReferenceValue(String type, 102 Clazz referencedClass, 103 IntegerValue arrayLength) 104 { 105 return type == null ? 106 REFERENCE_VALUE_NULL : 107 new ArrayReferenceValue(ClassConstants.TYPE_ARRAY + type, 108 referencedClass, 109 arrayLength); 110 } 111 } 112
