Latest Java Interview Questions and Answers Pdf Free Download
1. What is the most important feature of Java?
Java is a platform independent language.
2. What do you mean by platform independence?
Platform independence means that we can write and compile the java code in one platform (eg Windows) and can execute the class in any other supported platform eg (Linux,Solaris,etc).
3. Are JVM's platform independent?
JVM's are not platform independent. JVM's are platform specific run time implementation provided by the vendor.
4. What is a JVM?
JVM is Java Virtual Machine which is a run time environment for the compiled java class files.
5. What is the difference between a JDK and a JVM?
JDK is Java Development Kit which is for development purpose and it includes execution environment also. But JVM is purely a run time environment and hence you will not be able to compile your source files using a JVM.
Re: Latest Java Interview Questions and Answers Pdf Free Download
1. How to define a constant variable in Java?
The variable should be declared as static and final. So only one copy of the variable exists for all instances of the class and the value can't be changed also.
static final int PI = 2.14; is an example for constant.
2. Should a main method be compulsorily declared in all java classes?
No not required. main method should be defined only if the source class is a java application.
3. What is the return type of the main method?
Main method doesn't return anything hence declared void.
4. Why is the main method declared static?
main method is called by the JVM even before the instantiation of the class hence it is declared as static.