1 /* 2 * Copyright (c) 2012, 2014, 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 import java.lang.reflect.Constructor; 26 import java.lang.reflect.Executable; 27 import java.lang.reflect.Field; 28 import java.lang.reflect.Method; 29 30 /** 31 * Provides access to the metadata of a class typically provided in a class file. 32 */ 33 public interface MetaAccessProvider { 34 35 /** 36 * Returns the resolved Java type representing a given Java class. 37 * 38 * @param clazz the Java class object 39 * @return the resolved Java type object 40 */ 41 ResolvedJavaType lookupJavaType(Class<?> clazz); 42 43 /** 44 * Returns the resolved Java types representing some given Java classes. 45 * 46 * @param classes the Java class objects 47 * @return the resolved Java type objects 48 */ 49 default ResolvedJavaType[] lookupJavaTypes(Class<?>[] classes) { 50 ResolvedJavaType[] result = new ResolvedJavaType[classes.length]; 51 for (int i = 0; i < result.length; i++) { 52 result[i] = lookupJavaType(classes[i]); 53 } 54 return result; 55 } 56 57 /** 58 * Provides the {@link ResolvedJavaMethod} for a {@link Method} or {@link Constructor} obtained 59 * via reflection. 60 */ 61 ResolvedJavaMethod lookupJavaMethod(Executable reflectionMethod); 62 63 /** 64 * Provides the {@link ResolvedJavaField} for a {@link Field} obtained via reflection. 65 */ 66 ResolvedJavaField lookupJavaField(Field reflectionField); 67 68 /** 69 * Returns the resolved Java type of the given {@link JavaConstant} object. 70 * 71 * @return {@code null} if {@code constant.isNull() || !constant.kind.isObject()} 72 */ 73 ResolvedJavaType lookupJavaType(JavaConstant constant); 74 75 /** 76 * Returns the number of bytes occupied by this constant value or constant object. 77 * 78 * @param constant the constant whose bytes should be measured 79 * @return the number of bytes occupied by this constant 80 */ 81 long getMemorySize(JavaConstant constant); 82 83 /** 84 * Parses a 85 * <a href="http://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.3.3">method 86 * descriptor</a> into a {@link Signature}. The behavior of this method is undefined if the 87 * method descriptor is not well formed. 88 */ 89 Signature parseMethodDescriptor(String methodDescriptor); 90 91 /** 92 * Encodes a deoptimization action and a deoptimization reason in an integer value. 93 * 94 * @param debugId an integer that can be used to track the origin of a deoptimization at 95 * runtime. There is no guarantee that the runtime will use this value. The runtime 96 * may even keep fewer than 32 bits. 97 * 98 * @return the encoded value as an integer 99 */ 100 JavaConstant encodeDeoptActionAndReason(DeoptimizationAction action, DeoptimizationReason reason, int debugId); 101 102 DeoptimizationReason decodeDeoptReason(JavaConstant constant); 103 104 DeoptimizationAction decodeDeoptAction(JavaConstant constant); 105 106 int decodeDebugId(JavaConstant constant); 107 }