JAVA中关于对像的读写

Posted 2020-09-27 云上咖啡

 1 /**
 2  * 针对对象的文件读写
 3  */
 4 
 5 //导入包
 6 import java.io.File;
 7 import java.io.FileInputStream;
 8 import java.io.FileNotFoundException;
 9 import java.io.FileOutputStream;
10 import java.io.IOException;
11 import java.io.ObjectInputStream;
12 import java.io.ObjectOutputStream;
13 import java.util.HashMap;
14 
15 public class qwe {
16 
17     public static void main(String[] args) {
18         try {
19             File f = new File("D:\\\\Desktop\\\\NewFile\\\\hasKey.txt");//关联文件
20             FileOutputStream wr = new FileOutputStream("D:\\\\Desktop\\\\NewFile\\\\hasKey.txt");//文件写
21             ObjectOutputStream objw = new ObjectOutputStream(wr);//创建对象输出流
22             FileInputStream re = new FileInputStream("D:\\\\Desktop\\\\NewFile\\\\hasKey.txt");//读文件
23             ObjectInputStream objr = new ObjectInputStream(re); //创建对象输入流
24             HashMap<String,String> has = new HashMap<String,String>();//创建集合
25             has.put("001", "hello")    ;                
26             
27             objw.writeObject(has);//从对象输出流中写入                                
28             HashMap<String, String> has1 = (HashMap<String, String>) objr.readObject();//从对象输入流中读（强制转换类型）
29             
30             System.out.println(has1);                        
31                                                              
32         } catch (FileNotFoundException e) {//无文件异常捕获
33             // TODO Auto-generated catch block
34             e.printStackTrace();
35         }
36         catch (IOException e) {//捕获IO异常
37             // TODO Auto-generated catch block
38             e.printStackTrace();
39         }catch (ClassNotFoundException e) {//捕获不存在的类型的异常
40                 
41                 e.printStackTrace();
42             }
43         
44         
45     }
46 
47 }

运行结果为

 

存入文本的数据是