xref: /aosp_15_r20/art/test/617-clinit-oome/src/Main.java (revision 795d594fd825385562da6b089ea9b2033f3abf5a)

/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

public class Main {
    private static int exhaustJavaHeap(Object[] data, int index, int size) {
        Runtime.getRuntime().gc();
        while (size > 0) {
            try {
                data[index] = new byte[size];
                index++;
            } catch (OutOfMemoryError e) {
                size /= 2;
            }
        }
        return index;
    }

    public static void main(String[] args) {
        Class klass = Other.class;
        Object[] data = new Object[100000];
        try {
            System.out.println("Filling heap");

            // Make sure that there is no reclaimable memory in the heap. Otherwise we may throw
            // OOME to prevent GC thrashing, even if later allocations may succeed.
            Runtime.getRuntime().gc();
            System.runFinalization();
            // NOTE: There is a GC invocation in the exhaustJavaHeap(). So we don't need one here.

            int index = 0;
            int initial_size = 256 * 1024 * 1024;
            // Repeat to ensure there is no space left on the heap.
            index = exhaustJavaHeap(data, index, initial_size);
            index = exhaustJavaHeap(data, index, /*size*/ 4);
            index = exhaustJavaHeap(data, index, /*size*/ 4);

            // Initialize now that the heap is full.
            Other.print();
        } catch (OutOfMemoryError e) {
        } catch (Exception e) {
            System.out.println(e);
        }
    }
}