import java. io. *;
public class Demo1 { private static final File file = new File ( "operate/src/operate419/demo/demo2/user.txt" ) ; static { if ( file. exists ( ) || ! file. canRead ( ) ) { try { System. out. println ( "===" ) ; boolean newFile = file. createNewFile ( ) ; if ( ! newFile) { System. out. println ( "文件创建失败,文件路径错误" ) ; } } catch ( IOException e) { e. printStackTrace ( ) ; } } } public static void main ( String[ ] args) { addUser ( ) ; loadUser ( ) ; } private static void loadUser ( ) { try ( ObjectInputStream input = new ObjectInputStream ( new FileInputStream ( file) ) ) { Object o = input. readObject ( ) ; System. out. println ( o) ; } catch ( Exception e) { e. printStackTrace ( ) ; } } private static void addUser ( ) { try ( ObjectOutputStream out = new ObjectOutputStream ( new FileOutputStream ( file) ) ) { User user1 = new User ( 26 , "张三" ) ; User user2 = new User ( 376 , "李四" ) ; User user3 = new User ( 34 , "王二麻子" ) ; out. writeObject ( user1) ; out. writeObject ( user2) ; out. writeObject ( user3) ; } catch ( IOException e) { e. printStackTrace ( ) ; } }
}
import java. io. Serializable; public class User implements Serializable { private int age; private String name; @Override public String toString ( ) { return "User{" + "age=" + age + ", name='" + name + '\'' + '}' ; } @Override public boolean equals ( Object o) { if ( this == o) return true ; if ( o == null || getClass ( ) != o. getClass ( ) ) return false ; User user = ( User) o; if ( age != user. age) return false ; return name != null ? name. equals ( user. name) : user. name == null; } @Override public int hashCode ( ) { int result = age; result = 31 * result + ( name != null ? name. hashCode ( ) : 0 ) ; return result; } public int getAge ( ) { return age; } public void setAge ( int age) { this . age = age; } public String getName ( ) { return name; } public void setName ( String name) { this . name = name; } public User ( int age, String name) { this . age = age; this . name = name; } public User ( ) { }
}