[Java] IO streams - file character stream --FileReader, FileWriter

FileReader

Role: for reading character streams

Construction method:

FileReader(File file)

Create a new FileReader , given File read.

FileReader(String fileName)

Creates a new FileReader , name of the file to be read given.

Common methods:

1）int read();
2）int read(char[] cbuf)
3）int read(char[] cbuf,int off,int len);
4） int available();
5）close();

 

Code

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;

public class TestFileReader {
    public static void main(String[] args) throws IOException {
        FileReader reader=null;
        //(1)搭桥
        reader=new FileReader("F://test.txt");
        
        @ (2) reads
 //         int reader.Read B = (); // int type data to the read character
 @         of System.out.print ((char) B);
        
//         int B = 0; // for each read character data storing integer value
 //         the while (! (B = reader.Read ()) = -. 1) {
 //             of System.out.print (( char) B);
 //         }
        
        int len = 0; // stored character number read number 
        char [] = CBUF new new  char [1024 ];
        
        while((len=reader.read(cbuf))!=-1) {
            System.out.print(new String(cbuf, 0, len));
        }
        
        @ (3) off 
        reader.Close ();
    }
}

 

FileWriter

Role: for writing character streams

 

Construction method:

FileWriter(File file)

 

A File object to construct a FileWriter object. Given a file name with a Boolean value indicating whether additional data is written.

 

FileWriter(File file, boolean append)

 

A File object to construct a FileWriter object

 

FileWriter(String fileName)

Constructs a FileWriter object given a file name.

FileWriter(String fileName, boolean append)

 

Constructs a FileWriter object, is given a file name with a Boolean value indicating whether the data additional writing.

 

Common methods:

 

1）void write(int c);
2）void write(char[] cbuf);
3）abstract void write(char[] cbuf,int off,int len);
4）void write(String str);
5）abstract void flush();
6）void close();

 

Code

 

import java.io.FileWriter;
import java.io.IOException;

public class TestFileWriter {
    public static void main(String[] args) {
        //创建对象
        FileWriter writer=null;
        try {
            Writer = new new FileWriter ( "F: //dest.txt" );
             // write data 
            writer.Write ( "the Hello World!"); // write data to the buffer 
            writer.flush ();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally {
            try {
                if(writer!=null) {
                    //关闭
                    writer.close();
                }
            } catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }
        }
        
    }
}