BufferedOutputStream与NIO写文件对比

原创

1058106015 2022-12-07 14:36:22 博主文章分类：JavaSE ©著作权

文章标签 java System List 文章分类 运维

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数据内容（一行）如下所示

{"MAF":3.86,
    
    

     "BASE_STATION":"1823,4207,460,0,37;18431,4207,460,0,25;1822,4207,460,0,25;",
    
    

     "PID_010B":"",
    
    

     "FUEL":10.49,
    
    

     "REMARK":31922,
    
    

     "MILAGE":18.94,
    
    

     "PID_010C":"",
    
    

     "PID_010F":"",
    
    

     "RECEIVED_TIME":"2013-12-04 14:41:59",
    
    

     "GATHERTIME":"2013-12-04 14:41:49",
    
    

     "BABV":10.59,
    
    

     "ACCSTATUS":"0",
    
    

     "OBD_SPEED":145,
    
    

     "G_FORCE":-0.49}

第一次：（磁盘非常卡）

名称	文件数	数据条数	单条数据大小	线程数	耗时(s)	备注
BufferedOutputStream	100	7200	约310字节	200	611.557	XP系统，4G内存，4核CPU、apache commons-io组件
FileChannel	100	7200	约310字节	200	637.867	XP系统，4G内存，4核CPU

第二次：（CPU 100%）

名称	文件数	数据条数	单条数据大小	线程数	耗时(s)	备注
BufferedOutputStream	10000	7200	约310字节	200	1963.642	linux系统，2G内存，4核CPU
FileChannel	10000	7200	约310字节	200	1953.116	linux系统，2G内存，4核CPU

代码：

package com.sides.file;

import java.io.File;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;

/****************************************************************************
 * com.sides.file WriteFile.java Created on 2013-12-3
 * @Author: linfenliang
 * @Description:
 * @Version: 1.0
 ***************************************************************************/
public class WriteFile {
  /**
   * @param args
   * void
   * @date 2013-12-3
   * @version V1.0.0
   * @author linfenliang
   * @throws ExecutionException 
   * @throws InterruptedException 
   */
  public static void main(String[] args) throws InterruptedException, ExecutionException {
    ExecutorService service = Executors.newFixedThreadPool(200);
    long t0 = System.nanoTime();
    Future<Boolean> future = null;
    for(int i=0;i<10000;i++){
      WriterThread task = new WriterThread(DataFactory.dataList, String.format("/var/lib/log/nio/OBD_DATA%s.dat", i),true);
      future = service.submit(task);
    }
    boolean b = future.get();
    long t1 = System.nanoTime();
    System.out.println(b+",time cost ms:"+(t1-t0)/1000000);

    System.out.println("NIO is OK, ready to BufferedOutputStream write");
    Thread.sleep(5*1000);

    long t2 = System.nanoTime();
    Future<Boolean> future2 = null;
    for(int i=0;i<10000;i++){
      WriterThread task = new WriterThread(DataFactory.dataList, String.format("/var/lib/log/buffer/OBD_DATA%s.dat",i),false);
      future2 = service.submit(task);
    }
    boolean isOk = future2.get();
    long t3 = System.nanoTime();
    System.out.println(isOk+",time cost ms:"+(t3-t2)/1000000);


    System.out.println("BufferedOutputStream is OK, ready to  exit");
    Thread.sleep(5*1000);

    System.exit(0);




//    deleteFolder("/var/lib/log");
  }

  static void deleteFolder(String path) {
    File f = new File(path);
    if (f.isDirectory()) {
      File[] files = f.listFiles();
      for (File file : files) {
        if (!file.isDirectory()) {
          file.deleteOnExit();
        } else {
          deleteFolder(file.getAbsolutePath());
          boolean b = file.delete();
          System.out.println(b+"--"+file.getAbsolutePath());
        }
      }
    }
}
}    

     
   
package com.sides.file;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.concurrent.Callable;

import net.sf.json.JSONArray;
import net.sf.json.JSONObject;

import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.log4j.Logger;

/****************************************************************************
 * com.sides.file WriterThread.java Created on 2013-12-3
 * 
 * @Author: linfenliang
 * @Description:
 * @Version: 1.0
 ***************************************************************************/
public class WriterThread implements Callable<Boolean> {
  private static final Logger logger = Logger.getLogger(WriterThread.class);
  private List<Map<String,Object>> dataList;
  private String filePath;
  private boolean nioWrite;
  public WriterThread(List<Map<String,Object>> dataList,String filePath,boolean isNio){
    this.dataList = dataList;
    this.filePath = filePath;
    this.nioWrite = isNio;
  }
  @Override
  public Boolean call() throws Exception {
    try {
      File folder = new File(this.filePath).getParentFile();
      if(!folder.exists()){
        folder.mkdir();
      }
      JSONArray dataArr = JSONArray.fromObject(dataList,DataFactory.jsonConfig);
      for(int i=0;i<720;i++){
        if(nioWrite){
          nioWriteFile(filePath, dataArr);
        }else{
          commonIoWriteFile(filePath, dataArr);
        }
      }
    } catch (Exception e) {
      System.err.println(String.format("data list write error,source data is :%s, filePath is :%s, error message is:%s", dataList,filePath,e));
      return false;
    }
    System.out.println(this.filePath + "finished");
    return true;
  }
  static final void commonIoWriteFile(final String fileName, final Collection data) throws IOException{
    FileUtils.writeLines(new File(fileName), "UTF-8", data, IOUtils.LINE_SEPARATOR_UNIX, true);
  }
  static final void nioWriteFile(final String fileName, final JSONArray arr) throws IOException{
    FileOutputStream fops = new FileOutputStream(fileName,true);
    FileChannel writeChannel = fops.getChannel();
    JSONObject obj = null;
    Iterator<JSONObject> iter = arr.iterator();
    while(iter.hasNext()){
      obj = iter.next();
      writeChannel.write(ByteBuffer.wrap(obj.toString().concat(IOUtils.LINE_SEPARATOR_UNIX).getBytes()));
    }
    writeChannel.close();
    fops.close();
  }
}