Java IO流总结（1）

港控/mmm° 2022-08-21 07:57 219阅读 0赞

//流总结

package com.test.io;
    
    
    import java.io.BufferedInputStream;
    import java.io.BufferedOutputStream;
    import java.io.BufferedReader;
    import java.io.BufferedWriter;
    import java.io.File;
    import java.io.FileInputStream;
    import java.io.FileOutputStream;
    import java.io.FileReader;
    import java.io.FileWriter;
    import java.io.IOException;
    
    
    import org.junit.Test;
    
    
    /**
     * 处理流的使用
     * 节点流（4个）：                                         处理流
     * FileInputStream           BufferedInputStream    (flush())
     * FileOutputStream			 BufferedOutputStream	(flush())
     * FileReader                BufferedReader         (flush()) readLine 读一行
     * FileWriter                BufferedWriter        (flush())
     * @author mxr
     * 处理流是升级得到的
     */
    
    
    
    
    public class BufferStream {
    	public void testReader(){
    		File file = new File("H:/javatext/aa.txt");
    		BufferedReader br = null;
    		BufferedWriter bw = null;
    		try {
    			 br = new BufferedReader(new FileReader(file));
    			 bw = new BufferedWriter(new FileWriter(new File("H:/javatext/nn.txt")));
    			 String str;//结尾不等于空
    			 while((str = br.readLine())!=null){
    				// System.out.println(str);
    				 bw.write(str);
    				 bw.newLine();   //重新起一行
    				 bw.flush();
    			 }
    			 
    		} catch (IOException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}finally{
    			if(bw!=null){
    				try {
    					bw.close();
    				} catch (IOException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    			}
    			if(br!=null){
    				try {
    					br.close();
    				} catch (IOException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    			}
    		}
    		
    	}
    	
    	@Test
    	//缓存流的非文本文件的复制
    	public void test(){
    		BufferedInputStream bis = null;
    		BufferedOutputStream bos = null;
    		try {
    			File src = new File("H:/javatext/111.doc");
    			File dest = new File("H:/javatext/22.doc");
    			//2.创建响应的节点流，FileInputStream，FileOutputStream
    			bis = new BufferedInputStream(new FileInputStream(src));
    			bos = new BufferedOutputStream(new FileOutputStream(dest));
    			//实现文件的复制
    			int len;
    			byte[] b = new  byte[1024];//lKB=1024B
    			while((len = bis.read(b))!=-1){
    				bos.write(b, 0, len);
    				//BufferedOutputStream阻塞式的所以需要刷新
    				bos.flush();
    			}
    		} catch (Exception e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}finally{
    			//关缓冲流就可以了，他会自动关闭牛节点流
    			if(bos != null){
    				try {
    					bis.close();
    				} catch (IOException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    			}
    			if(bos != null){
    				try {
    					bis.close();
    				} catch (IOException e) {
    					// TODO Auto-generated catch block
    					e.printStackTrace();
    				}
    			}
    		}
    	}
    }