com.streamsets.pipeline.api.ext.io.CountingReader Maven / Gradle / Ivy
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/*
* Copyright 2017 StreamSets Inc.
*
* 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 com.streamsets.pipeline.api.ext.io;
import java.io.IOException;
import java.io.Reader;
public class CountingReader extends ProxyReader {
private long pos;
private long count;
private long markLimit = 0;
private long readAfterMark = 0;
public CountingReader(Reader reader) {
super(reader);
}
@Override
public long skip(long ln) throws IOException {
final long skip = super.skip(ln);
this.count += skip;
this.pos += skip;
updateMarkState(skip);
return skip;
}
@Override
protected void afterRead(int n) {
if (n != -1) {
this.count += n;
this.pos += n;
updateMarkState(n);
}
}
private void updateMarkState(long n) {
if (markLimit > 0) {
readAfterMark += n;
if (readAfterMark > markLimit) {
markLimit = 0;
readAfterMark = 0;
}
}
}
public long getPos() {
return pos;
}
public long getCount() {
return this.count;
}
public long resetCount() {
long tmp = this.count;
this.count = 0;
markLimit = 0;
readAfterMark = 0;
return tmp;
}
@Override
public void mark(int idx) throws IOException {
super.mark(idx);
markLimit = idx;
readAfterMark = 0;
}
@Override
public void reset() throws IOException {
super.reset();
count -= readAfterMark;
pos -= readAfterMark;
}
}