net.sandius.rembulan.lib.impl.io.SeekableInputStream Maven / Gradle / Ivy
/*
* Copyright 2016 Miroslav Janíček
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package net.sandius.rembulan.lib.impl.io;
import net.sandius.rembulan.util.Check;
import java.io.IOException;
import java.io.InputStream;
public class SeekableInputStream extends InputStream implements SeekableStream {
private final InputStream in;
private long position;
public SeekableInputStream(InputStream in) {
this.in = Check.notNull(in);
this.position = 0L;
}
@Override
public int read() throws IOException {
int result = in.read();
if (result != -1) {
position += 1;
}
return result;
}
@Override
public long getPosition() {
return position;
}
@Override
public long setPosition(long newPosition) {
position = newPosition;
return position;
}
@Override
public long addPosition(long offset) {
long newPosition = position + offset;
if (position < 0) {
throw new IllegalArgumentException("Illegal argument");
}
else {
return setPosition(newPosition);
}
}
}