java读写文本文件

接触java有很长一段时间，越来越能体会到语言真的只是一种工具，经常利用java对数据进行清洗，所以最经常用的功能就是文本的读取和写入，但是这最最基本的用法我却用的不熟练，每次用都要翻之前的project，现在特意贴在这边，也方便自己查找。

1、读取文本文件

public static void read(String fp) throws IOException{
        try {
            BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(fp)));
            String data="";            
            while((data=br.readLine())!=null){
                System.out.println(data);
                
            }
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
    }

2.一种覆盖性写入的代码

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;

/**
 * @author 
 
   */
public class WriteTxtFileByName {
    private String filename = null;
    
    public WriteTxtFileByName(String filename) {
        this.filename = filename;
    }
    
    public void writeFileByName(String content) {
        File docFile = new File(filename);
        try {
            docFile.createNewFile();
            FileOutputStream txtfile = new FileOutputStream(docFile);
            PrintStream p = new PrintStream(txtfile);
            p.println(content);
            txtfile.close();
            p.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    
    public static void main(String[] args) {
        WriteTxtFileByName wfbn = new WriteTxtFileByName("e:/title.txt");
        wfbn.writeFileByName("content");
        wfbn.writeFileByName("title");
        wfbn.writeFileByName("label");
    }
}

3.写入数据

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

/**
 * @author  
   */
public class WriteTxtFileByName {
        
    public static void writeFileByName(String fp) {
        try{
            FileWriter fileWriter=new FileWriter(fp);
            fileWriter.write("*Vertices "+7);//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
            fileWriter.write("
");//!!!!!!!!!!!!!!!!
            fileWriter.write("*Matrix");//!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
            fileWriter.flush();
            fileWriter.close();
        }catch(Exception e){
            e.printStackTrace();
        }
        
    }
    
    public static void main(String[] args) {
        writeFileByName("e:/title.txt");
        
    }
}