System.out.println means

Question

Can any one explain what is "system.out.println"
i need to know each individual li,e "System" means what , form which class and why it is used
simillary for "out" and "println"

Answer 1

There is a class called System.
It has a static member attribute called "out", which is of type PrintStream.
PrintStream provides a method called "println", which is what you're calling.
Here's a similar example:
// This is playing the role of PrintStream
public class Foo {
   // This method is playing the role of println()
   public void bar() {
      System.out.println("Hello");
// This is playing the role of System
public class Test {
   // This attribute is playing the role of the out attribute in the System class
   public static Foo out = new Foo();
// Here's the code to go with it:
Test.out.bar();  // Prints "Hello"See the similarity ?
Test.out.bar();versus
System.out.println("...");The documentation for the System class is here:
http://java.sun.com/j2se/1.4.2/docs/api/java/lang/System.html
The documentation for all the rest of the classes is here:
http://java.sun.com/j2se/1.4.2/docs/api/index.html