1/* 2 * Copyright (c) 2010, 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. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 */ 23 24/* @test 25 * @summary Ensure that InputStreamReader reads as many characters as possible 26 */ 27 28// InputStreamReader is not required by its spec to read as many characters as 29// possible upon each invocation of read(char[], int, int), but many programs 30// (e.g., javac) depend upon this behavior. 31 32import java.io.*; 33 34 35public class FullRead { 36 37 static int MAX_LEN = 1 << 16; 38 39 static void test(File f, int len) throws Exception { 40 FileOutputStream fo = new FileOutputStream(f); 41 for (int i = 0; i < len; i++) 42 fo.write('x'); 43 fo.close(); 44 45 FileInputStream fi = new FileInputStream(f); 46 Reader rd = new InputStreamReader(fi, "US-ASCII"); 47 char[] cb = new char[MAX_LEN + 100]; 48 int n = rd.read(cb, 0, cb.length); 49 System.out.println(len + " : " + n); 50 if (len != n) 51 throw new Exception("Expected " + len + ", read " + n); 52 } 53 54 public static void main(String[] args) throws Exception { 55 File f = File.createTempFile("foo", "bar"); 56 f.deleteOnExit(); 57 System.out.println(f); 58 59 for (int i = 4; i <= MAX_LEN; i <<= 1) 60 test(f, i); 61 } 62 63} 64