java _io_字符缓冲流的输入输出

Posted 2022-05-18

新增方法:

输入:
BufferedReader breader=new BufferedReader(Reader reader);
.readLine()读取一行内容，返回字符串
输出:
BufferedWriter bwriter=new BufferedWirter(Writer writer);
.newLine() 写入一个换行符

输入:
File f =new File("C:\Users\10853\eclipse-workspace\hell\src\hell\abc");
BufferedReader reader=null;
try

        reader=new BufferedReader(new FileReader(f));

        String line=null;
        while((line=reader.readLine())!=null)//要添上!=null，不像c语言赋值表达式整个也有个真假结果
        
            System.out.println(line);
        
    catch(FileNotFoundException e)
    
        e.printStackTrace();
    catch(IOException e)
    
        e.printStackTrace();
    finally 

        try 
            if(null!=reader)
            
                reader.close();
            
        catch(IOException e)
        
            e.printStackTrace();
        
    

输出:

    File f=new File("D:d/c.txt");

    BufferedWriter bwriter=null;
    try
    
        bwriter=new BufferedWriter(new FileWriter(f));

        String s="addad";
        bwriter.write(s);
        bwriter.newLine();
        bwriter.append("aaaff");
        bwriter.flush();
    catch(FileNotFoundException e)
    
        e.printStackTrace();
    catch(IOException e)
    
        e.printStackTrace();
    finally 
        try 
            if(null!=bwriter)
            
                bwriter.close();
            
        catch(IOException e)
        
            e.printStackTrace();