138 lines
4.3 KiB
Java
138 lines
4.3 KiB
Java
/*
|
|
* Copyright (c) 1999, 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 4150737
|
|
@summary Ensure that StreamTokenizer does not read any further ahead
|
|
than is absolutely necessary
|
|
*/
|
|
|
|
import java.io.ByteArrayInputStream;
|
|
import java.io.InputStream;
|
|
import java.io.InputStreamReader;
|
|
import java.io.Reader;
|
|
import java.io.StreamTokenizer;
|
|
import java.io.IOException;
|
|
|
|
|
|
public class ReadAhead {
|
|
|
|
|
|
/* An InputStream subclass that cannot read past a given limit */
|
|
private static class LimitedInputStream extends InputStream {
|
|
|
|
private String input;
|
|
private int limit; /* Do not allow input[limit] to be read */
|
|
private int next = 0;
|
|
|
|
public LimitedInputStream(String input, int limit) {
|
|
this.input = input;
|
|
this.limit = limit;
|
|
}
|
|
|
|
public int read() throws IOException {
|
|
if (next >= limit)
|
|
throw new IOException("Attempted to read too far in stream");
|
|
return input.charAt(next++);
|
|
}
|
|
|
|
}
|
|
|
|
|
|
/* A Reader subclass that cannot read past a given limit */
|
|
private static class LimitedReader extends Reader {
|
|
|
|
private String input;
|
|
private int limit; /* Do not allow input[limit] to be read */
|
|
private int next = 0;
|
|
|
|
public LimitedReader(String input, int limit) {
|
|
this.input = input;
|
|
this.limit = limit;
|
|
}
|
|
|
|
public int read() throws IOException {
|
|
if (next >= limit)
|
|
throw new IOException("Attempted to read too far in stream");
|
|
return input.charAt(next++);
|
|
}
|
|
|
|
public int read(char[] b, int off, int len) throws IOException {
|
|
int top = off + len;
|
|
int i;
|
|
for (i = off; i < top; i++) {
|
|
int c = read();
|
|
if (c < 0) break;
|
|
b[i] = (char)c;
|
|
}
|
|
return i - off;
|
|
}
|
|
|
|
public void close() { }
|
|
|
|
}
|
|
|
|
|
|
/* Interface for objects that can create new StreamTokenizers
|
|
with a given limited input */
|
|
private static interface StreamTokenizerMaker {
|
|
public StreamTokenizer create(String input, int limit);
|
|
}
|
|
|
|
private static void fail(String why) throws Exception {
|
|
throw new Exception(why);
|
|
}
|
|
|
|
private static void test(StreamTokenizer st) throws Exception {
|
|
st.eolIsSignificant(true);
|
|
int tt = st.nextToken();
|
|
if (tt != StreamTokenizer.TT_WORD) fail("expected TT_WORD");
|
|
if (!st.sval.equals("foo")) fail("expected word token \"foo\"");
|
|
tt = st.nextToken();
|
|
if (tt != StreamTokenizer.TT_EOL) fail("expected TT_EOL");
|
|
}
|
|
|
|
private static void test(StreamTokenizerMaker stm) throws Exception {
|
|
test(stm.create("foo\nx", 4));
|
|
test(stm.create("foo\r\nx", 4));
|
|
}
|
|
|
|
|
|
public static void main(String[] args) throws Exception {
|
|
|
|
/* InputStream case */
|
|
test(new StreamTokenizerMaker() {
|
|
public StreamTokenizer create(String input, int limit) {
|
|
return new StreamTokenizer(new LimitedInputStream(input, limit));
|
|
}});
|
|
|
|
/* Reader case */
|
|
test(new StreamTokenizerMaker() {
|
|
public StreamTokenizer create(String input, int limit) {
|
|
return new StreamTokenizer(new LimitedReader(input, limit));
|
|
}});
|
|
|
|
}
|
|
|
|
}
|