| /* |
| * Copyright (c) 2003, 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 4806007 |
| * @summary Checks for vague exceptions from writeUTF/readUTF |
| * @key randomness |
| */ |
| |
| import java.io.*; |
| import java.util.*; |
| |
| public class ReadUTF { |
| |
| private static Random generator = new Random(); |
| |
| private static final int TEST_ITERATIONS = 1000; |
| |
| private static final int A_NUMBER_NEAR_65535 = 60000; |
| |
| private static final int MAX_CORRUPTIONS_PER_CYCLE = 3; |
| |
| public static final void main(String[] args) throws Exception { |
| for (int i=0; i<TEST_ITERATIONS; i++) { |
| try { |
| writeAndReadAString(); |
| } catch (UTFDataFormatException utfdfe) { |
| if (utfdfe.getMessage() == null) |
| throw new RuntimeException("vague exception thrown"); |
| } catch (EOFException eofe) { |
| // These are rare and beyond the scope of the test |
| } |
| } |
| } |
| |
| private static void writeAndReadAString() throws Exception { |
| // Write out a string whose UTF-8 encoding is quite possibly |
| // longer than 65535 bytes |
| int length = generator.nextInt(A_NUMBER_NEAR_65535) + 1; |
| ByteArrayOutputStream baos = new ByteArrayOutputStream(); |
| StringBuffer testBuffer = new StringBuffer(); |
| for (int i=0; i<length; i++) |
| testBuffer.append((char)generator.nextInt()); |
| String testString = testBuffer.toString(); |
| DataOutputStream dos = new DataOutputStream(baos); |
| dos.writeUTF(testString); |
| |
| // Corrupt the data to produce malformed characters |
| byte[] testBytes = baos.toByteArray(); |
| int dataLength = testBytes.length; |
| int corruptions = generator.nextInt(MAX_CORRUPTIONS_PER_CYCLE); |
| for (int i=0; i<corruptions; i++) { |
| int index = generator.nextInt(dataLength); |
| testBytes[index] = (byte)generator.nextInt(); |
| } |
| |
| // Pay special attention to mangling the end to produce |
| // partial characters at end |
| testBytes[dataLength-1] = (byte)generator.nextInt(); |
| testBytes[dataLength-2] = (byte)generator.nextInt(); |
| |
| // Attempt to decode the bytes back into a String |
| ByteArrayInputStream bais = new ByteArrayInputStream(testBytes); |
| DataInputStream dis = new DataInputStream(bais); |
| dis.readUTF(); |
| } |
| } |