| /* |
| * Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.tools.classfile; |
| |
| import java.util.ArrayList; |
| import java.util.HashSet; |
| import java.util.List; |
| import java.util.Objects; |
| import java.util.Set; |
| import com.sun.tools.classfile.Instruction.TypeKind; |
| import static com.sun.tools.classfile.ConstantPool.*; |
| |
| /** |
| * A utility class to find where in a ClassFile references |
| * a {@link CONSTANT_Methodref_info method}, |
| * a {@link CONSTANT_InterfaceMethodref_info interface method, |
| * or a {@link CONSTANT_Fieldref_info field}. |
| */ |
| public final class ReferenceFinder { |
| /** |
| * Filter for ReferenceFinder of what constant pool entries for reference lookup. |
| */ |
| public interface Filter { |
| /** |
| * Decides if the given CPRefInfo entry should be accepted or filtered. |
| * |
| * @param cpool ConstantPool of the ClassFile being parsed |
| * @param cpref constant pool entry representing a reference to |
| * a fields method, and interface method. |
| * @return {@code true} if accepted; otherwise {@code false} |
| */ |
| boolean accept(ConstantPool cpool, CPRefInfo cpref); |
| } |
| |
| /** |
| * Visitor of individual method of a ClassFile that references the |
| * accepted field, method, or interface method references. |
| */ |
| public interface Visitor { |
| /** |
| * Invoked for a method containing one or more accepted CPRefInfo entries |
| * |
| * @param cf ClassFile |
| * @param method Method that does the references the accepted references |
| * @param refs Accepted constant pool method/field reference |
| */ |
| void visit(ClassFile cf, Method method, List<CPRefInfo> refConstantPool); |
| } |
| |
| private final Filter filter; |
| private final Visitor visitor; |
| |
| /** |
| * Constructor. |
| */ |
| public ReferenceFinder(Filter filter, Visitor visitor) { |
| this.filter = Objects.requireNonNull(filter); |
| this.visitor = Objects.requireNonNull(visitor); |
| } |
| |
| /** |
| * Parses a given ClassFile and invoke the visitor if there is any reference |
| * to the constant pool entries referencing field, method, or |
| * interface method that are accepted. This method will return |
| * {@code true} if there is one or more accepted constant pool entries |
| * to lookup; otherwise, it will return {@code false}. |
| * |
| * @param cf ClassFile |
| * @return {@code true} if the given class file is processed to lookup |
| * references |
| * @throws ConstantPoolException if an error of the constant pool |
| */ |
| public boolean parse(ClassFile cf) throws ConstantPoolException { |
| List<Integer> cprefs = new ArrayList<Integer>(); |
| int index = 1; |
| for (ConstantPool.CPInfo cpInfo : cf.constant_pool.entries()) { |
| if (cpInfo.accept(cpVisitor, cf.constant_pool)) { |
| cprefs.add(index); |
| } |
| index += cpInfo.size(); |
| } |
| |
| if (cprefs.isEmpty()) { |
| return false; |
| } |
| |
| for (Method m : cf.methods) { |
| Set<Integer> ids = new HashSet<Integer>(); |
| Code_attribute c_attr = (Code_attribute) m.attributes.get(Attribute.Code); |
| if (c_attr != null) { |
| for (Instruction instr : c_attr.getInstructions()) { |
| int idx = instr.accept(codeVisitor, cprefs); |
| if (idx > 0) { |
| ids.add(idx); |
| } |
| } |
| } |
| if (ids.size() > 0) { |
| List<CPRefInfo> refInfos = new ArrayList<CPRefInfo>(ids.size()); |
| for (int id : ids) { |
| refInfos.add(CPRefInfo.class.cast(cf.constant_pool.get(id))); |
| } |
| visitor.visit(cf, m, refInfos); |
| } |
| } |
| return true; |
| } |
| |
| private ConstantPool.Visitor<Boolean,ConstantPool> cpVisitor = |
| new ConstantPool.Visitor<Boolean,ConstantPool>() |
| { |
| public Boolean visitClass(CONSTANT_Class_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitInterfaceMethodref(CONSTANT_InterfaceMethodref_info info, ConstantPool cpool) { |
| return filter.accept(cpool, info); |
| } |
| |
| public Boolean visitMethodref(CONSTANT_Methodref_info info, ConstantPool cpool) { |
| return filter.accept(cpool, info); |
| } |
| |
| public Boolean visitFieldref(CONSTANT_Fieldref_info info, ConstantPool cpool) { |
| return filter.accept(cpool, info); |
| } |
| |
| public Boolean visitDouble(CONSTANT_Double_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitFloat(CONSTANT_Float_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitInteger(CONSTANT_Integer_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitInvokeDynamic(CONSTANT_InvokeDynamic_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitLong(CONSTANT_Long_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitNameAndType(CONSTANT_NameAndType_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitMethodHandle(CONSTANT_MethodHandle_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitMethodType(CONSTANT_MethodType_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitString(CONSTANT_String_info info, ConstantPool cpool) { |
| return false; |
| } |
| |
| public Boolean visitUtf8(CONSTANT_Utf8_info info, ConstantPool cpool) { |
| return false; |
| } |
| }; |
| |
| private Instruction.KindVisitor<Integer, List<Integer>> codeVisitor = |
| new Instruction.KindVisitor<Integer, List<Integer>>() |
| { |
| public Integer visitNoOperands(Instruction instr, List<Integer> p) { |
| return 0; |
| } |
| |
| public Integer visitArrayType(Instruction instr, TypeKind kind, List<Integer> p) { |
| return 0; |
| } |
| |
| public Integer visitBranch(Instruction instr, int offset, List<Integer> p) { |
| return 0; |
| } |
| |
| public Integer visitConstantPoolRef(Instruction instr, int index, List<Integer> p) { |
| return p.contains(index) ? index : 0; |
| } |
| |
| public Integer visitConstantPoolRefAndValue(Instruction instr, int index, int value, List<Integer> p) { |
| return p.contains(index) ? index : 0; |
| } |
| |
| public Integer visitLocal(Instruction instr, int index, List<Integer> p) { |
| return 0; |
| } |
| |
| public Integer visitLocalAndValue(Instruction instr, int index, int value, List<Integer> p) { |
| return 0; |
| } |
| |
| public Integer visitLookupSwitch(Instruction instr, int default_, int npairs, int[] matches, int[] offsets, List<Integer> p) { |
| return 0; |
| } |
| |
| public Integer visitTableSwitch(Instruction instr, int default_, int low, int high, int[] offsets, List<Integer> p) { |
| return 0; |
| } |
| |
| public Integer visitValue(Instruction instr, int value, List<Integer> p) { |
| return 0; |
| } |
| |
| public Integer visitUnknown(Instruction instr, List<Integer> p) { |
| return 0; |
| } |
| }; |
| } |
| |
