Java equals Functions

All classes in java are subclasses of objects. The equals method is implemented in the Object, which must be overloaded in general.

When no overload is performed

Public class JavaTest {public static void main (String [] args) {boolean result; Student stu1 = new Student ("cjc", 24 ); student stu2 = new Student ("cjc", 24); result = stu1.equals (stu2); if (result) {System. out. println ("is the same person! ");} Else {System. out. println (" not the same person! ") ;}} Class Student extends Object {private String name; private int age; Student (String str, int num) {name = str; age = num ;}}

After reload

Public class JavaTest {public static void main (String [] args) {boolean result; Student stu1 = new Student ("cjc", 24 ); student stu2 = new Student ("cjc", 24); result = stu1.equals (stu2); if (result) {System. out. println ("is the same person! ");} Else {System. out. println (" not the same person! ") ;}} Class Student extends Object {private String name; private int age; Student (String str, int num) {name = str; age = num ;} public boolean equals (Object o) {boolean result = false; if (o instanceof Student) {Student stu = (Student) o; if (stu. name. equals (this. name) & this. age = stu. age) {result = true ;}} return result ;}}

It should be noted that the String class has been overloaded with equals, so stu. name. equals (this. name) in the program can be used in this way.