Java example source code file (MalformedSurrogates.java)

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Java - Java tags/keywords

bad, bytearrayoutputstream, char, exception, high, malformedsurrogates, outputstreamwriter, string, utf8, utf\-8, utf_8

The MalformedSurrogates.java Java example source code

/*
 * Copyright (c) 2008, 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 4153987
   @summary Malformed surrogates should be handled by the converter in
   substitution mode.
 */

import java.io.*;

public class MalformedSurrogates {

    public static void main(String[] args) throws Exception {

        String fe = System.getProperty("file.encoding");
        if (  fe.equalsIgnoreCase("UTF8")
              || fe.equalsIgnoreCase("UTF-8")
              || fe.equalsIgnoreCase("UTF_8"))
            // This test is meaningless if the default charset
            // does handle surrogates
            return;

        System.out.println("Testing string conversion...");
        /* Example with malformed surrogate, and an offset */
        String t = "abc\uD800\uDB00efgh";
        String t2 = t.substring(2);
        byte[] b = t2.getBytes();
        System.err.println(b.length);
        for (int i = 0; i < b.length; i++)
            System.err.println("[" + i + "]" + "=" + (char) b[i]
                               + "=" + (int) b[i]);
        if (b.length != 7) {
            throw new Exception("Bad string conversion for bad surrogate");
        }

        /* Example with a proper surrogate, no offset. Always worked */
        String t3 = "abc\uD800\uDC00efgh";
        byte[] b2 = t3.getBytes();
        System.out.println(b2.length);
        for(int i = 0; i < b2.length; i++)
            System.err.println("[" + i + "]" + "=" + (char) b2[i]);
        if (b2.length != 8) {
            throw new Exception("Bad string conversion for good surrogate");
        }

        OutputStream os = new ByteArrayOutputStream();
        OutputStreamWriter osw = new OutputStreamWriter(os);
        System.out.println("Testing flush....");
        /* Check for the case where the converter has a left over
           high surrogate when flush is called on the converter */
        osw.flush();
        String s = "abc\uD800"; // High surrogate
        char[] c = s.toCharArray();
        osw.write(s, 0, 4);
        osw.flush();

        System.out.println("Testing convert...");
        /* Verify that all other characters go through */
        for (int k = 1; k < 65535 ; k++) {
            osw.write("Char[" + k + "]=\"" + ((char) k) + "\"");
        }

    }
}