1 /* 2 * Copyright (c) 2009, 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.meta; 24 25 /** 26 * Represents a method signature provided by the runtime. 27 * 28 * @see <a href="http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.3.3">Method 29 * Descriptors</a> 30 */ 31 public interface Signature { 32 33 /** 34 * Returns the number of parameters in this signature, adding 1 for a receiver if requested. 35 * 36 * @param receiver true if 1 is to be added to the result for a receiver 37 * @return the number of parameters; + 1 iff {@code receiver == true} 38 */ 39 int getParameterCount(boolean receiver); 40 41 /** 42 * Gets the parameter type at the specified position. 43 * 44 * @param index the index into the parameters, with {@code 0} indicating the first parameter 45 * @param accessingClass the context of the type lookup. If non-null, its class loader is used 46 * for resolving the type. If {@code null}, then the type returned is either 47 * unresolved or a resolved type whose resolution is context free (e.g., a primitive 48 * type or a type in a java.* package). 49 * @return the {@code index}'th parameter type 50 * @throws LinkageError if {@code accessingClass != null} and resolution fails 51 * 52 */ 53 JavaType getParameterType(int index, ResolvedJavaType accessingClass); 54 55 /** 56 * Gets the parameter kind at the specified position. This is the same as calling 57 * {@link #getParameterType}. {@link JavaType#getJavaKind getJavaKind}. 58 * 59 * @param index the index into the parameters, with {@code 0} indicating the first parameter 60 * @return the kind of the parameter at the specified position 61 */ 62 default JavaKind getParameterKind(int index) { 63 return getParameterType(index, null).getJavaKind(); 64 } 65 66 /** 67 * Gets the return type of this signature. 68 * 69 * @param accessingClass the context of the type lookup. If non-null, its class loader is used 70 * for resolving the type. If {@code null}, then the type returned is either 71 * unresolved or a resolved type whose resolution is context free (e.g., a primitive 72 * type or a type in a java.* package). 73 * @return the return type 74 * @throws LinkageError if {@code accessingClass != null} and resolution fails 75 */ 76 JavaType getReturnType(ResolvedJavaType accessingClass); 77 78 /** 79 * Gets the return kind of this signature. This is the same as calling {@link #getReturnType}. 80 * {@link JavaType#getJavaKind getJavaKind}. 81 */ 82 default JavaKind getReturnKind() { 83 return getReturnType(null).getJavaKind(); 84 } 85 86 /** 87 * Gets the <a 88 * href="http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.3.3">method 89 * descriptor</a> corresponding to this signature. For example: 90 * 91 * <pre> 92 * (ILjava/lang/String;D)V 93 * </pre> 94 * 95 * @return the signature as a string 96 */ 97 default String toMethodDescriptor() { 98 StringBuilder sb = new StringBuilder("("); 99 for (int i = 0; i < getParameterCount(false); ++i) { 100 sb.append(getParameterType(i, null).getName()); 101 } 102 sb.append(')').append(getReturnType(null).getName()); 103 return sb.toString(); 104 } 105 106 default JavaType[] toParameterTypes(JavaType receiverType) { 107 int args = getParameterCount(false); 108 JavaType[] result; 109 int i = 0; 110 if (receiverType != null) { 111 result = new JavaType[args + 1]; 112 result[0] = receiverType; 113 i = 1; 114 } else { 115 result = new JavaType[args]; 116 } 117 for (int j = 0; j < args; j++) { 118 result[i + j] = getParameterType(j, null); 119 } 120 return result; 121 } 122 123 default JavaKind[] toParameterKinds(boolean receiver) { 124 int args = getParameterCount(false); 125 JavaKind[] result; 126 int i = 0; 127 if (receiver) { 128 result = new JavaKind[args + 1]; 129 result[0] = JavaKind.Object; 130 i = 1; 131 } else { 132 result = new JavaKind[args]; 133 } 134 for (int j = 0; j < args; j++) { 135 result[i + j] = getParameterKind(j); 136 } 137 return result; 138 } 139 }