/*
* Copyright (c) 1997, 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 4016710
@summary check for correct implementation of InputStream.skip
*/
import java.io.*;
public class Skip{
private static void dotest(InputStream in , int curpos ,
long total , long toskip , long expected)
throws Exception
{
try {
System.err.println("\n\nCurrently at pos = " + curpos +
"\nTotal bytes in the Stream = " + total +
"\nNumber of bytes to skip = " + toskip +
"\nNumber of bytes that should be skipped = " +
expected);
long skipped = in.skip(toskip);
System.err.println("actual number skipped: "+ skipped);
if ((skipped < 0) || (skipped > expected)) {
throw new RuntimeException("Unexpected number of bytes skipped");
}
} catch (IOException e) {
System.err.println("IOException is thrown - possible result");
} catch (Throwable e) {
throw new RuntimeException("Unexpected "+e+" is thrown!");
}
}
public static void main( String argv[] ) throws Exception {
MyInputStream in = new MyInputStream(11);
/* test for negative skip */
dotest(in, 0, 11, -23, 0);
/* check for skip beyond EOF starting from before EOF */
dotest(in, 0, 11, 20, 11);
/* check for skip after EOF */
dotest(in, -1, 11, 20, 0);
in = new MyInputStream(9000);
/* check for skip equal to the read chunk size in InputStream.java */
dotest(in, 0, 9000, 2048, 2048);
/* check for skip greater than the read chunk size in InputStream.java */
dotest(in, 2048, 9000, 5000, 5000);
/* check for skip beyond EOF starting from before EOF */
dotest(in, 7048, 9000, 5000, 1952);
in = new MyInputStream(5000);
/* check for multiple chunk reads */
dotest(in, 0, 5000, 6000, 5000);
/*
* check for skip larger than Integer.MAX_VALUE
* (Takes about 2 hrs on a sparc ultra-1)
* long total = (long)Integer.MAX_VALUE + (long)10;
* long toskip = total - (long)6;
* in = new MyInputStream(total);
* dotest(in, 0, total, toskip, toskip);
*/
}
}
class MyInputStream extends InputStream {
private int readctr = 0;
private long endoffile;
public MyInputStream(long endoffile) {
this.endoffile = endoffile;
}
public int read() {
if (readctr == endoffile) {
return -1;
}
else {
readctr++;
return 0;
}
}
public int available() { return 0; }
}