/*
    * 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.giraph.utils;
  
  import org.apache.log4j.Logger;
  
  /**
   * Print log messages only if the time is met.  Thread-safe.
   */
  public class TimedLogger {
    /** Last time printed */
    private volatile long lastPrint = System.currentTimeMillis();
    /** Minimum interval of time to wait before printing */
    private final int msecs;
    /** Logger */
    private final Logger log;
  
    /**
     * Constructor of the timed logger
     *
     * @param msecs Msecs to wait before printing again
     * @param log Logger to print to
     */
    public TimedLogger(int msecs, Logger log) {
      this.msecs = msecs;
      this.log = log;
    }
  
    /**
     * Print to the info log level if the minimum waiting time was reached.
     *
     * @param msg Message to print
     */
    public void info(String msg) {
      if (isPrintable()) {
        log.info(msg);
      }
    }
  
    /**
     * Is the log message printable (minimum interval met)?
     *
     * @return True if the message is printable
     */
    public boolean isPrintable() {
      if (System.currentTimeMillis() > lastPrint + msecs) {
        lastPrint = System.currentTimeMillis();
        return true;
      }
  
      return false;
    }
  }