FileWriter字符流写入

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

public class FileWriterTest {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        File fl = new File("D:\\workspace\\FileWriterTest\\src\\123.txt");
        //System.exit(0);        
        FileWriter fw = null;
        try {
            fw = new FileWriter(fl);
            String s = "我的一天123";
            fw.write(s);
                    
            
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            
            if(fw!=null)
            {
                try {
                    fw.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
    }

}

fw.write(); 有好多重载，可以选择合适的

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

public class FileWriterTest {

    public static void main(String[] args) {
        // TODO Auto-generated method stub
        File fl = new File("D:\\workspace\\FileWriterTest\\src\\123.txt");
        //System.exit(0);        
        FileWriter fw = null;
        try {
            fw = new FileWriter(fl);
            String s = "我的一天123";
            //fw.write(s);
            for(int i=0;i<s.length();i++)
            {
                int j = s.charAt(i);
                fw.write(j);
            }
            fw.flush();
                    
            
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }finally{
            
            if(fw!=null)
            {
                try {
                    fw.close();
                } catch (IOException e) {
                    // TODO Auto-generated catch block
                    e.printStackTrace();
                }
            }
        }
    }

}