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 static java.nio.file.StandardOpenOption.*; 18 import java.nio.file.*; 19 import java.io.*; 20 import java.util.*; 21 22 public class Main { 23 private static final String TEMP_FILE_NAME_PREFIX = "oflimit"; 24 private static final String TEMP_FILE_NAME_SUFFIX = ".txt"; 25 main(String[] args)26 public static void main(String[] args) throws IOException { 27 28 // Exhaust the number of open file descriptors. 29 List<File> files = new ArrayList<File>(); 30 List<OutputStream> streams = new ArrayList<OutputStream>(); 31 try { 32 for (int i = 0; ; i++) { 33 File file = createTempFile(); 34 files.add(file); 35 streams.add(Files.newOutputStream(file.toPath(), CREATE, APPEND)); 36 } 37 } catch (Throwable e) { 38 if (e.getMessage().contains("Too many open files")) { 39 System.out.println("Message includes \"Too many open files\""); 40 } else { 41 System.out.println("Unexpected exception:"); 42 e.printStackTrace(); 43 } 44 } 45 46 // Now try to create a new thread. 47 try { 48 Thread thread = new Thread() { 49 public void run() { 50 System.out.println("thread run."); 51 } 52 }; 53 thread.start(); 54 thread.join(); 55 } catch (Throwable e) { 56 System.out.println(e.getMessage()); 57 } 58 59 for (int i = 0; i < streams.size(); i++) { 60 streams.get(i).close(); 61 } 62 63 for (int i = 0; i < files.size(); i++) { 64 files.get(i).delete(); 65 } 66 System.out.println("done."); 67 } 68 createTempFile()69 private static File createTempFile() throws Exception { 70 try { 71 return File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX); 72 } catch (IOException e) { 73 System.setProperty("java.io.tmpdir", "/data/local/tmp"); 74 try { 75 return File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX); 76 } catch (IOException e2) { 77 System.setProperty("java.io.tmpdir", "/sdcard"); 78 return File.createTempFile(TEMP_FILE_NAME_PREFIX, TEMP_FILE_NAME_SUFFIX); 79 } 80 } 81 } 82 } 83