java Questions and Answers

When we start a thread by applying start() method on it ,how does it knows that to execute run()method?

Can you make an instance of an abstract class? For example - java.util.Calender is an abstract class with a method getInstance() which returns an instance of the Calender class.

What is meant by "Abstract Interface"?

In System.out.println(),what is System,out and println,pls explain?

Where and how can you use a private constructor.

What is the difference between final, finally and finalize?

Why Java does not support multiple inheritence ?

Can a private method of a superclass be declared within a subclass?

How can I convert my Java classes to an executable .EXE file for Windows?

What causes out of memory exceptions?

How can I generate random numbers?

How do I run the garbage collector to free memory and delete unused objects?

What is the difference between Serializable and Externalizable interface?

Difference between Externalizable and Serializable

The compiler assumes that the programmer will always pass an object to the method, either ArrayList or LinkedList or Vector?

Why wrapper variables (even final static ones) aren't considered constants

All api java java 6.0 java 7.0 jdbc jsp servlet ejb jndi jms ejb 3.0 j2ee jee 5.0 jee 6.0 jsf struts spring Hibernate ajax JBoss Seam netbeans eclipse ant xml maven dojo junit javafx j2me log4j ESB JBoss Apache Quartz scjp mysql oracle gwt openjpa jmx yui google-guice android JBoss scwcd 5.0 scjp 1.5 scjp 1.6 scja scbcd 5.0

When we start a thread by applying start() method on it ,how does it knows that to execute run()method?

About Wrapper class in Java

Static Block and Static Initializer in Java

What is the difference between the Boolean & operator and the && operator?

What is the purpose of finalization?

What is the difference between preemptive scheduling and time slicing?

Does garbage collection guarantee that a program will not run out of memory?

What are wrapped classes?

What is the difference between yielding and sleeping?

What are synchronized methods and synchronized statements?

What is synchronization and why is it important?

How are Observer and Observable used?

What is a transient variable?

What is native code?

What is the Java Virtual Machine?

What is the difference between Swing and AWT components?