Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Explain the equals() method
The equals() method of java.lang.Object acts the similar as the == operator; that is, it tests for object identity rather than object equality. The implicit contract of the equals() method, thus, is that it tests for equality rather than identity. Therefore most classes will override equals() along with a version that does field through field comparisons before deciding while to return true or false.
To elaborate, an object created through a clone() method (that is a copy of the object) should pass the equals() test if neither the original nor the clone has changed because the clone was created. Therefore the clone will fail to be == to the original object.
For instance, here is an equals() method you could use for the Car class. Two cars are equal if and only if their license plates are equal, and that's what this techniques tests for. public boolean equals(Object o) { if (o instanceof Car) { Car c = (Car) o; if (this.licensePlate.equals(c.licensePlate)) return true; } return false; }This example is particularly interesting since it demonstrates the impossibility of writing a useful generic equals() method in which tests equality for any object. It is not sufficient to easily test for equality of all the fields of two objects. It is whole possible that some of the fields might not be relevant to the test for equality as in this instance where changing the speed of a car does not change the in fact car that's referred to.
Be careful to prevent this common mistake when writing equals() methods: public boolean equals(Car c) { if (o instanceof Car) { Car c = (Car) o; if (this.licensePlate.equals(c.licensePlate)) return true; } return false; }The equals() method must permit tests against any object of any class, not simply against other objects of the similar class (Car in this example.)
You do not requires to test whether o is null. null is never an instance of any class. null instanceof Object returns false.
The Struts tag libraries are: ? HTML Tags ? Logic Tags ? Template Tags ? Bean Tags ? Tiles Tags ? Nested Tags
A one page website where a user can input the information including Company Name, Title, Activity, R/S, I also need the user to select the start date, end date, and check poi
Java SDK is not so comfortable with people used to command line interpreter. IDEs contain compilers, editors, debugging facilities, drag and drop methods, etc. This compiler strive
Want to Design an all encompassing Database for a small business Project Description: I want to organize and structure an all encompassing database and Information management
Struts framework is an open-source framework for producing the web applications in Java EE, based on MVC-2 architecture. It uses and extends the Java Servlet API. Struts are robust
Give the example of mixing data type in java? Mixing Data Types Order can form a difference while data types are mixed. For example, 1 / 2 * 3.5 = 0.0 3.5 * 1 / 2 = 1.75 3.5 /
how do you access a value of an array?
two different object may have chance to have same behavier but property must be different why?
Java Message Service: An interface executed by most J2EE containers to give point-to-point queueing and topic (publish/subscribe) behavior. JMS is frequently used by EJB's that req
I am preparing ehopsital project. For the needs of hospital in that billing module and patient registration and stores module and e.t.c module is there for hospital needs. Skill
Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd