001/* 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 * 017 */ 018package org.apache.bcel.verifier.structurals; 019 020 021import org.apache.bcel.generic.InstructionHandle; 022 023/** 024 * This interface defines properties of JVM bytecode subroutines. 025 * Note that it is 'abused' to maintain the top-level code in a 026 * consistent fashion, too. 027 * 028 * @version $Id: Subroutine.java 1747278 2016-06-07 17:28:43Z britter $ 029 */ 030public interface Subroutine{ 031 /** 032 * Returns all the JsrInstructions that have the 033 * first instruction of this subroutine as their target. 034 * <B>Must not be invoked on the 'top-level subroutine'.</B> 035 */ 036 InstructionHandle[] getEnteringJsrInstructions(); 037 038 /** 039 * Returns the one and only RET that leaves the subroutine. 040 * Note that JustIce has a pretty rigid notion of a subroutine. 041 * <B>Must not be invoked on the 'top-level subroutine'.</B> 042 * 043 * @see Subroutines 044 */ 045 InstructionHandle getLeavingRET(); 046 047 /** 048 * Returns all instructions that together form this subroutine. 049 * Note that an instruction is part of exactly one subroutine 050 * (the top-level code is considered to be a special subroutine) - 051 * else it is not reachable at all (dead code). 052 */ 053 InstructionHandle[] getInstructions(); 054 055 /** 056 * Returns if the given InstructionHandle refers to an instruction 057 * that is part of this subroutine. This is a convenience method 058 * that saves iteration over the InstructionHandle objects returned 059 * by getInstructions(). 060 * 061 * @see #getInstructions() 062 */ 063 boolean contains(InstructionHandle inst); 064 065 /** 066 * Returns an int[] containing the indices of the local variable slots 067 * accessed by this Subroutine (read-accessed, write-accessed or both); 068 * local variables referenced by subroutines of this subroutine are 069 * not included. 070 * 071 * @see #getRecursivelyAccessedLocalsIndices() 072 */ 073 int[] getAccessedLocalsIndices(); 074 075 /** 076 * Returns an int[] containing the indices of the local variable slots 077 * accessed by this Subroutine (read-accessed, write-accessed or both); 078 * local variables referenced by subroutines of this subroutine are 079 * included. 080 * 081 * @see #getAccessedLocalsIndices() 082 */ 083 int[] getRecursivelyAccessedLocalsIndices(); 084 085 /** 086 * Returns the subroutines that are directly called from this subroutine. 087 */ 088 Subroutine[] subSubs(); 089}