--- /dev/null 2017-05-19 18:25:31.000000000 -0700 +++ new/test/javax/imageio/ReadBitsTest.java 2017-05-19 18:25:31.000000000 -0700 @@ -0,0 +1,90 @@ +/* + * Copyright (c) 2001, 2017, 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. + */ + +/* + * @test + * @bug 4416800 + * @summary Checks that ImageInputStreamImpl.readBit and readBits handle the bit + * offset correctly + */ + +import java.io.ByteArrayInputStream; +import java.io.IOException; +import java.io.InputStream; + +import javax.imageio.stream.FileCacheImageInputStream; +import javax.imageio.stream.ImageInputStream; + +public class ReadBitsTest { + public static void main(String[] args) throws IOException { + byte[] buffer = new byte[] {(byte)169, (byte)85}; // 10101001 01010101 + InputStream ins = new ByteArrayInputStream(buffer); + ImageInputStream in = new FileCacheImageInputStream(ins,null); + + if (in.getBitOffset() != 0) { + throw new RuntimeException("Initial bit offset != 0!"); + } + + int bit0 = in.readBit(); // 1 + if (bit0 != 1) { + throw new RuntimeException("First bit != 1"); + } + if (in.getBitOffset() != 1) { + throw new RuntimeException("Second bit offset != 1"); + } + + long bits1 = in.readBits(5); // 01010 = 10 + if (bits1 != 10) { + throw new RuntimeException("Bits 1-5 != 10 (= " + bits1 + ")"); + } + if (in.getBitOffset() != 6) { + throw new RuntimeException("Third bit offset != 6"); + } + + int bit1 = in.readBit(); // 0 + if (bit1 != 0) { + throw new RuntimeException("Bit 6 != 0"); + } + if (in.getBitOffset() != 7) { + throw new RuntimeException("Third bit offset != 7"); + } + + long bits2 = in.readBits(8); // 10101010 = 170 + if (bits2 != 170) { + throw new RuntimeException("Bits 7-14 != 170 (= " + bits2 + ")"); + } + if (in.getBitOffset() != 7) { + throw new RuntimeException("Fourth bit offset != 7"); + } + + int bit2 = in.readBit(); // 1 + if (bit2 != 1) { + throw new RuntimeException("Bit 15 != 1"); + } + if (in.getBitOffset() != 0) { + throw new RuntimeException("Fifth bit offset != 0"); + } + + in.close(); + } +}