io之FileInputStream

package com.laien.io;

import java.io.FileInputStream;
import java.io.InputStream;

/**
 * 从硬盘中把数据读到内存中，谓之INPUT
 * @author Administrator
 *
 */
public class InputStreamTest {

	public static void main(String[] args) throws Exception {
		InputStream fileInputStream = new FileInputStream("D:/test.txt");

		byte[] buffer = new byte[200];
		//每次读到的长度
		int length = 0;
		//流写下到buffer中,从0开始，每次最多读200字节，返回读取的长度，读取完成后，长度会返回-1
		while (-1 != (length = fileInputStream.read(buffer, 0, 200))) {
			String str = new String(buffer, 0, length);
			
			System.out.print(str);
		}
		
		fileInputStream.close();
	}

}