java读写（追加）文件

java 读: 

import java.io.*; public class Main { public static void main(String[] args){ try { BufferedReader in = new BufferedReader(new FileReader("url")); String str; while ((str = in.readLine()) != null) {///一次读一行 System.out.println(str); } System.out.println(str); } catch (IOException ex) { System.out.println(ex.getMessage() + "读取异常"); } } }

java 写：

import java.io.*; public class Main { public static void main(String[] args) { try { BufferedWriter out = new BufferedWriter(new FileWriter("url/要追加的文件名",true)); ///若文件不存在，会自动创建，若存在，就自动追加 out.write("××××××");/// 写入内容 /// 写入的内容为字符串。若需要写入 如：int,double 等，可用String.valueof() 将int或double 转为字符串读入 out.close(); System.out.println("文件创建成功！"); } catch (IOException e) { System.out.println("创建异常"); } } }