1 /* 2 * Copyright (C) 2016 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 import java.lang.reflect.Method; 18 19 public class Main { 20 public static void main(String[] args) { 21 System.loadLibrary(args[0]); 22 23 // Get all methods. We cannot call getDeclaredMethod("foo") as 24 // that would make "foo" a strong root. 25 Method[] methods = Main.class.getDeclaredMethods(); 26 27 // Call getName on the methods, which is implemented by using the dex 28 // cache and calling setResolvedString. 29 for (int i = 0; i < methods.length; i++) { 30 methods[i].getName(); 31 } 32 33 // Compile Main.foo. "foo" needs to be a strong root for JIT compilation. 34 // We stress test this: 35 // - avoid strongly interning "foo" by doing "f" + "oo" 36 // - call GC so that weaks can be collected. 37 // - invoke foo() to make sure "foo" hasn't been collected. 38 ensureJitCompiled(Main.class, "f" + "oo"); 39 Runtime.getRuntime().gc(); 40 foo(); 41 } 42 43 public static void foo() { 44 System.out.println("foo"); 45 } 46 47 public static native void ensureJitCompiled(Class cls, String method_name); 48 } 49
