【Java】IO流--文件字符流--FileReader、FileWriter

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)读取
//        int b=reader.read();//读取到的字符的int类型数据
//        System.out.print((char)b);
        
//        int b=0;//用于存储每次读到的字符数据的整数值
//        while((b=reader.read())!=-1) {
//            System.out.print((char)b);
//        }
        
        int len=0;//储存读到的字符的个数数
        char[] cbuf=new char[1024];
        
        while((len=reader.read(cbuf))!=-1) {
            System.out.print(new String(cbuf, 0, len));
        }
        
        //(3)关闭
        reader.close();
    }
}

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 FileWriter("F://dest.txt");
            //写数据
            writer.write("Hello World!");//数据写到了缓冲区
            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();
            }
        }
        
    }
}