1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.android.ahat; 18 19 import com.android.tools.perflib.heap.ClassObj; 20 import com.android.tools.perflib.heap.Field; 21 import com.android.tools.perflib.heap.Instance; 22 import java.io.File; 23 import java.io.IOException; 24 import java.util.Map; 25 26 /** 27 * The TestDump class is used to get an AhatSnapshot for the test-dump 28 * program. 29 */ 30 public class TestDump { 31 // It can take on the order of a second to parse and process the test-dump 32 // hprof. To avoid repeating this overhead for each test case, we cache the 33 // loaded instance of TestDump and reuse it when possible. In theory the 34 // test cases should not be able to modify the cached snapshot in a way that 35 // is visible to other test cases. 36 private static TestDump mCachedTestDump = null; 37 38 private AhatSnapshot mSnapshot = null; 39 40 /** 41 * Load the test-dump.hprof file. 42 * The location of the file is read from the system property 43 * "ahat.test.dump.hprof", which is expected to be set on the command line. 44 * For example: 45 * java -Dahat.test.dump.hprof=test-dump.hprof -jar ahat-tests.jar 46 * 47 * An IOException is thrown if there is a failure reading the hprof file. 48 */ TestDump()49 private TestDump() throws IOException { 50 String hprof = System.getProperty("ahat.test.dump.hprof"); 51 mSnapshot = AhatSnapshot.fromHprof(new File(hprof)); 52 } 53 54 /** 55 * Get the AhatSnapshot for the test dump program. 56 */ getAhatSnapshot()57 public AhatSnapshot getAhatSnapshot() { 58 return mSnapshot; 59 } 60 61 /** 62 * Return the value of a field in the DumpedStuff instance in the 63 * snapshot for the test-dump program. 64 */ getDumpedThing(String name)65 public Object getDumpedThing(String name) { 66 ClassObj main = mSnapshot.findClass("Main"); 67 Instance stuff = null; 68 for (Map.Entry<Field, Object> fields : main.getStaticFieldValues().entrySet()) { 69 if ("stuff".equals(fields.getKey().getName())) { 70 stuff = (Instance) fields.getValue(); 71 } 72 } 73 return InstanceUtils.getField(stuff, name); 74 } 75 76 /** 77 * Get the test dump. 78 * An IOException is thrown if there is an error reading the test dump hprof 79 * file. 80 * To improve performance, this returns a cached instance of the TestDump 81 * when possible. 82 */ getTestDump()83 public static synchronized TestDump getTestDump() throws IOException { 84 if (mCachedTestDump == null) { 85 mCachedTestDump = new TestDump(); 86 } 87 return mCachedTestDump; 88 } 89 } 90