JAVA中关于对像的读写

/**
 * 针对对象的文件读写
 */

//导入包
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.util.HashMap;

public class qwe {

    public static void main(String[] args) {
        try {
            File f = new File("D:\Desktop\NewFile\hasKey.txt");//关联文件
            FileOutputStream wr = new FileOutputStream("D:\Desktop\NewFile\hasKey.txt");//文件写
            ObjectOutputStream objw = new ObjectOutputStream(wr);//创建对象输出流
            FileInputStream re = new FileInputStream("D:\Desktop\NewFile\hasKey.txt");//读文件
            ObjectInputStream objr = new ObjectInputStream(re); //创建对象输入流
            HashMap<String,String> has = new HashMap<String,String>();//创建集合
            has.put("001", "hello")    ;                
            
            objw.writeObject(has);//从对象输出流中写入                                
            HashMap<String, String> has1 = (HashMap<String, String>) objr.readObject();//从对象输入流中读（强制转换类型）
            
            System.out.println(has1);                        
                                                             
        } catch (FileNotFoundException e) {//无文件异常捕获
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        catch (IOException e) {//捕获IO异常
            // TODO Auto-generated catch block
            e.printStackTrace();
        }catch (ClassNotFoundException e) {//捕获不存在的类型的异常
                
                e.printStackTrace();
            }
        
        
    }

}

运行结果为

存入文本的数据是