1 /* 2 * Copyright (c) 2014, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 package jdk.vm.ci.hotspot; 24 25 import jdk.vm.ci.meta.Constant; 26 import jdk.vm.ci.meta.JavaConstant; 27 import jdk.vm.ci.meta.JavaKind; 28 29 /** 30 * The compressed representation of the {@link JavaConstant#NULL_POINTER null constant}. 31 */ 32 public final class HotSpotCompressedNullConstant implements JavaConstant, HotSpotConstant { 33 34 public static final JavaConstant COMPRESSED_NULL = new HotSpotCompressedNullConstant(); 35 36 private HotSpotCompressedNullConstant() { 37 } 38 39 public JavaKind getJavaKind() { 40 return JavaKind.Object; 41 } 42 43 @Override 44 public boolean isNull() { 45 return true; 46 } 47 48 @Override 49 public boolean isCompressed() { 50 return true; 51 } 52 53 public Constant compress() { 54 throw new IllegalArgumentException(); 55 } 56 57 public Constant uncompress() { 58 return NULL_POINTER; 59 } 60 61 @Override 62 public boolean isDefaultForKind() { 63 return true; 64 } 65 66 @Override 67 public Object asBoxedPrimitive() { 68 throw new IllegalArgumentException(); 69 } 70 71 @Override 72 public int asInt() { 73 throw new IllegalArgumentException(); 74 } 75 76 @Override 77 public boolean asBoolean() { 78 throw new IllegalArgumentException(); 79 } 80 81 @Override 82 public long asLong() { 83 throw new IllegalArgumentException(); 84 } 85 86 @Override 87 public float asFloat() { 88 throw new IllegalArgumentException(); 89 } 90 91 @Override 92 public double asDouble() { 93 throw new IllegalArgumentException(); 94 } 95 96 @Override 97 public String toString() { 98 return JavaConstant.toString(this); 99 } 100 101 @Override 102 public String toValueString() { 103 return "null"; 104 } 105 106 @Override 107 public int hashCode() { 108 return System.identityHashCode(this); 109 } 110 111 @Override 112 public boolean equals(Object o) { 113 return o instanceof HotSpotCompressedNullConstant; 114 } 115 }