--- /dev/null 2015-05-07 15:03:50.000000000 +0100 +++ new/test/java/io/InputStream/ReadNBytes.java 2015-05-07 15:03:50.000000000 +0100 @@ -0,0 +1,111 @@ +/* + * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. + * + * This code is distributed in the hope that it will be useful, but WITHOUT + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ + +import java.io.ByteArrayInputStream; +import java.io.IOException; +import java.io.InputStream; +import java.util.Arrays; +import java.util.Random; + +/* + * @test + * @bug 8765432 + * @library /lib/testlibrary + * @build jdk.testlibrary.* + * @key randomness + * @summary Basic test for InputStream.readNBytes + */ +public class ReadNBytes { + + // TODO: Improve test coverage... + + private static Random generator = RandomFactory.getRandom(); + + public static void main(String[] args) throws IOException { + test(new byte[]{1, 2, 3}); + test(createRandomBytes(1024)); + test(createRandomBytes((1 << 13) - 1)); + test(createRandomBytes((1 << 13))); + test(createRandomBytes((1 << 13) + 1)); + test(createRandomBytes((1 << 15) - 1)); + test(createRandomBytes((1 << 15))); + test(createRandomBytes((1 << 15) + 1)); + test(createRandomBytes((1 << 17) - 1)); + test(createRandomBytes((1 << 17))); + test(createRandomBytes((1 << 17) + 1)); + } + + static void test(byte[] inputBytes) throws IOException { + int length = inputBytes.length; + InputStream in = new ByteArrayInputStream(inputBytes); + byte[] readBytes = new byte[roundUp(length) >> 1]; + int nread = in.readNBytes(readBytes, 0, readBytes.length); + + int x; + byte[] tmp; + check(nread == readBytes.length, + "Expected number of bytes read: " + readBytes.length + ", got: " + nread); + check(Arrays.equals((tmp = Arrays.copyOf(inputBytes, nread)), readBytes), + "Expected[" + tmp + "], got:[" + readBytes + "]"); + + // Read again + nread = in.readNBytes(readBytes, 0, readBytes.length); + + check(nread == length - readBytes.length, + "Expected number of bytes read: " + (length - readBytes.length) + ", got: " + nread); + check(Arrays.equals((tmp = Arrays.copyOfRange(inputBytes, readBytes.length, length)), + Arrays.copyOf(readBytes, nread)), + "Expected[" + tmp + "], got:[" + readBytes + "]"); + // Expect end of stream + check((x = in.read()) == -1, + "Expected end of stream from read(), got " + x); + check((x = in.read(tmp)) == -1, + "Expected end of stream from read(byte[]), got " + x); + check((x = in.read(tmp, 0, tmp.length)) == -1, + "Expected end of stream from read(byte[], int, int), got " + x); + check((x = in.readNBytes(tmp, 0, tmp.length)) == 0, + "Expected end of stream, 0, from readNBytes(byte[], int, int), got " + x); + } + + static byte[] createRandomBytes(int size) { + byte[] bytes = new byte[size]; + generator.nextBytes(bytes); + return bytes; + } + + private static int roundUp(int size) { + int x = Integer.highestOneBit(size); + if (x != size) + x = x << 1; + return x; + } + + static void check(boolean cond, Object ... failedArgs) { + if (cond) + return; + StringBuilder sb = new StringBuilder(); + for (Object o : failedArgs) + sb.append(o); + throw new RuntimeException(sb.toString()); + } +}