package test;

import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel;

public class Test {

	
	public static void main(String[] args) {
		try {
			FileInputStream fis=new FileInputStream("/home/tobacco/test/res.txt");
			int sum=0;
			int n;
			long t1=System.currentTimeMillis();
			try {
				while((n=fis.read())>=0){
					sum+=n;
				}
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			long t=System.currentTimeMillis()-t1;
			System.out.println("sum:"+sum+"  time:"+t);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		try {
			FileInputStream fis=new FileInputStream("/home/tobacco/test/res.txt");
			BufferedInputStream bis=new BufferedInputStream(fis);
			int sum=0;
			int n;
			long t1=System.currentTimeMillis();
			try {
				while((n=bis.read())>=0){
					sum+=n;
				}
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
			long t=System.currentTimeMillis()-t1;
			System.out.println("sum:"+sum+"  time:"+t);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		MappedByteBuffer buffer=null;
		try {
			buffer=new RandomAccessFile("/home/tobacco/test/res.txt","rw").getChannel().map(FileChannel.MapMode.READ_WRITE, 0, 1253244);
			int sum=0;
			int n;
			long t1=System.currentTimeMillis();
			for(int i=0;i<1253244;i++){
				n=0x000000ff&buffer.get(i);
				sum+=n;
			}
			long t=System.currentTimeMillis()-t1;
			System.out.println("sum:"+sum+"  time:"+t);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}

	}

}


//java/6477