1 /* 2 * Copyright (c) 2016, 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 package jdk.jshell; 26 27 import java.util.Arrays; 28 import java.util.HashMap; 29 import java.util.Objects; 30 import jdk.jshell.spi.ExecutionControl.ClassBytecodes; 31 32 /** 33 * Tracks the state of a class. 34 */ 35 class ClassTracker { 36 37 private final HashMap<String, ClassInfo> map; 38 39 ClassTracker() { 40 this.map = new HashMap<>(); 41 } 42 43 /** 44 * Associates a class name, class bytes (current and loaded). 45 */ 46 class ClassInfo { 47 48 // The name of the class 49 private final String className; 50 51 // The corresponding compiled class bytes when a load or redefine 52 // is started. May not be the loaded bytes. May be null. 53 private byte[] currentBytes; 54 55 // The class bytes successfully loaded/redefined into the remote VM. 56 private byte[] loadedBytes; 57 58 private ClassInfo(String className) { 59 this.className = className; 60 } 61 62 String getClassName() { 63 return className; 64 } 65 66 byte[] getLoadedBytes() { 67 return loadedBytes; 68 } 69 70 byte[] getCurrentBytes() { 71 return currentBytes; 72 } 73 74 void setCurrentBytes(byte[] bytes) { 75 this.currentBytes = bytes; 76 } 77 78 void setLoadedBytes(byte[] bytes) { 79 this.loadedBytes = bytes; 80 } 81 82 boolean isLoaded() { 83 return loadedBytes != null; 84 } 85 86 boolean isCurrent() { 87 return Arrays.equals(currentBytes, loadedBytes); 88 } 89 90 ClassBytecodes toClassBytecodes() { 91 return new ClassBytecodes(className, currentBytes); 92 } 93 94 @Override 95 public boolean equals(Object o) { 96 return o instanceof ClassInfo 97 && ((ClassInfo) o).className.equals(className); 98 } 99 100 @Override 101 public int hashCode() { 102 return Objects.hashCode(this.className); 103 } 104 } 105 106 void markLoaded(ClassBytecodes[] cbcs) { 107 for (ClassBytecodes cbc : cbcs) { 108 get(cbc.name).setLoadedBytes(cbc.bytecodes); 109 } 110 } 111 112 void markLoaded(ClassBytecodes[] cbcs, boolean[] isLoaded) { 113 for (int i = 0; i < cbcs.length; ++i) { 114 if (isLoaded[i]) { 115 ClassBytecodes cbc = cbcs[i]; 116 get(cbc.name).setLoadedBytes(cbc.bytecodes); 117 } 118 } 119 } 120 121 // Map a class name to the current compiled class bytes. 122 void setCurrentBytes(String className, byte[] bytes) { 123 ClassInfo ci = get(className); 124 ci.setCurrentBytes(bytes); 125 } 126 127 // Lookup the ClassInfo by class name, create if it does not exist. 128 ClassInfo get(String className) { 129 return map.computeIfAbsent(className, k -> new ClassInfo(k)); 130 } 131 }