/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You 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 org.apache.jmeter.save;

import java.io.PrintWriter;

import java.io.Writer;

import java.util.concurrent.atomic.AtomicLong;

import org.apache.jmeter.util.JMeterUtils;

/**

 * Decorator of PrintWriter

 * Simple goal is decreasing flush rate for high-throughput println() method

 */

public class WritebackPrintWriter extends PrintWriter{

    private static final long flush_period_in_bytes = JMeterUtils.getPropDefault("reporters.writeback.flush_period_in_bytes", 10240); // flush size bytes (every 10Kb)

    private static final long flush_period_in_ms = JMeterUtils.getPropDefault("reporters.writeback.flush_period_in_ms", 1000); //flush period in ms (every second)

    private AtomicLong last_flush_bytes = new AtomicLong(0);

    private AtomicLong last_flush_time = new AtomicLong(0);

    public WritebackPrintWriter(Writer bufferedWriter) { 

        super(bufferedWriter, false);

    }    

    @Override

    public void write(char buf[], int off, int len) {

        synchronized(this) {

            super.write(buf, off, len);

            last_flush_bytes.addAndGet(len-off);

        }

    }

    public void write(char c) {

        synchronized(this) {

            super.write(c);

            last_flush_bytes.addAndGet(1);

        }

    }

    @Override

    public void flush() {

        if(System.currentTimeMillis() - last_flush_time.get() > flush_period_in_ms

                || last_flush_bytes.get() > flush_period_in_bytes) {

            synchronized(this) {

                long time = System.currentTimeMillis();

                super.flush();

                last_flush_bytes.getAndSet(0);

                last_flush_time.getAndSet(time);

            }

        } else {

            //it's not your time

        }

    }

}

import org.apache.jmeter.save.WritebackPrintWriter;