The top level class in Java is class Object. Every other class inherits from Object and therefore Object is the top most in the class hierarchy.
If you extend a class from Object such as class Animal and further extend Animal with class Dog then the hierarchy is as follows:
Object
|
Animal
|
Dog
Code for this hierachy is as follows:
class Animal {
}
class Dog extends Animal {
}
We don't need to write class Animal extends Object because every class extends from Object so it does not need to be stated.
Connectivity in Java can be affected by internet connection, as well as the type of Java. There are times that if there is a poor connection, it can cause Java to not work properly. Java should be updated regularly.
Networking is a basic action. A servlet in Java is a single part of networking, a single task.
http://diaryproducts.net/about/programming_languages/java/convert_jsp_pages_to_jsp_documents_jspx_with_jsp2x
CATEGORY-SECTION-SUBSECTION-SUBHEADING
In the early 1990s James Gosling, a Sun Microsystems employee, created a programming language called Oak. He named the C based objected oriented language after an oak tree that he viewed outside the window of his office. When a group of Sun Microsystem employees visited a local coffee shop, they suggested the change of Oak’s name to Java to differentiate it from another programming language with the same name. Oak facilitated the communication between video game consoles and VCRs. Television set-top boxed for video-on-demand services was the intended use for the Oak application language. The World Wide Web evolved as set-top box manufacturers declined the software. To enter the software market for the World Wide Web, Oak’s developers shifted the focus to the Internet and WebRunner, an Oak-enabled browser. WebRunner became the HotJava web browser. Java is a pure object-oriented language. Humans learn about objects by examining the attributes and behaviors of objects such as cars, planes, computers, people, animals, plants, etc. The use of objects in the Java programming language is similar to the way people describe real-world objects. Class relationships group together similar characteristics of objects of a specified class – for example a class of vehicles. Object-oriented design (OOD) also models software components by their attributes and behaviors. Programmers use Java to develop either software applications or applets. Applications are programs that enable computer users to perform everyday tasks such as sending and receiving e-mail or performing calculations. An applet is a Java program embedded in a HyperText Markup Language (HTML) document. Loading the desired Web page(s) in an internet browser will execute Java applets. Java programs are portable since no programming changes are necessary for the original program to run on any supported hardware/operating system platform. There are five phases for the execution of Java programs. These are edit, compile, load, verify, and execute. Programs are coded using an editor. The compiler creates bytecodes. The class loader reads the files containing bytecodes and stores them in memory. The bytecode verifier validates the bytecodes in accordance with Java’s security restrictions. The interpreter reads the bytecodes and translates them into a computer language prior to program execution.
Class
define the data types
Object is the topmost class in the Java Class hierarchy. There is no Class above Object. All classes in Java are implicitly derived from Object.
It's part of the language specification that all objects in Java must inherit from Object. Java defines a strict class hierarchy, and enforcing a "super most class" ensures that this ordering is maintained.
First you would have to design the class hierarchy; perhaps on paper and pencil. Then you create the classes so that one depends on another, using the extends keyword.
Class hierarchy is a term used in Java. It is used for identifying the inheritance hierarchy or the parent class relationships Ex: Public class B extends C { } Public class A extends B { } Here if we take the class hierarchy for class 'A' it would be A
using javac command and mentioning fully classified class name. Fully classified here means class name along with the package hierarchy in which the class is stored in .java file
Because, the parent class also needs to be initialized when you create an object in the inheritance hierarchy.
The constructor will invoke all constructors in the inheritance hierarchy to ensure that all the parent classes of the current classes get initialized when the current class is instantiated.
The "Object" class is the topmost class in the class hierarchy. Classes inherit directly from this class by default; all classes inherit from Object directly or indirectly.
Java uses the least-abstract implementation of a method. If a method is called on an object, it searches the current object for an implementation. If no such implementation exists, Java looks to the object.super class for the method. It keeps searching up the superclass list until it finds a method or gets to the Object superclass and throws a NoSuchMethodException.
There is no hierarchy.