java读取txt文件实例有没有

java读取txt文件实例有没有

逐行读取文本内容
1.引包
	import java.io.BufferedReader;
	import java.io.File;
	import java.io.FileReader;

2.获得文件路径和文件名
	String filePathName = path + filename;

3.获得File对象，建立FileReader对象，并实例化为fr，建立BufferedReader对象，并实例化为br
	File file = new File(filePathName);
	FileReader fr = new FileReader(file);
	BufferedReader br = new BufferedReader(fr);

4.获得一行数据
	line = (String) br.readLine();

5.关闭BufferedReader，FileReader
	br.close();
	fr.close();

public class IOTest {
 public static void main(String[] args){
  File f = new File("E:\\1.txt");
  //读
  String oldStr = "";
  try {
   FileReader fr = new FileReader(f);
   BufferedReader br = new BufferedReader(fr);
   String line = null;
   while((line = br.readLine())!=null){
    oldStr += line;
   }
  } catch (FileNotFoundException e1) {
   e1.printStackTrace();
  } catch (IOException e) {
   e.printStackTrace();
  }
  
  //写
  String newStr = "zxc";
  FileWriter fw;
  try {
   fw = new FileWriter(f);
   BufferedWriter bw = new BufferedWriter(fw);
   bw.write(oldStr+"\r\n"+newStr);//不想换行就把\r\n去掉
   bw.close();
   fw.close();
  } catch (IOException e) {
   e.printStackTrace();
  }
 }
}
这样就ok了，自己总结的。

谢谢啊，以后多指教