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Question: How System.out.println() works?

Answer: System.out.println();incase System is a class in java.lang package.And out is the static field in the java.lang.System class. It works by a native method.

Category Java Interview Questions & Answers - Exam Mode / Learning Mode
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Question: How System.out.println() works?


System.out.println();incase System is a class in java.lang package.And out is the static field in the java.lang.System class. It works by a native method. Source:

println() is a method inside the PrintStream class.And "out" is a static object of PrintStream class which is inside a System class and is in Java.lang.*;
So that we refer it as
System.out.println(); Source:

Answered by: Samatha | Date: | Contact Samatha Contact Samatha

System is a class which helps in giving information / and access to out computer system.To check heap memory, system properties and so on.
Printstreem is a class which streems the data to the standard output. Now java people made an association by adding the object which is static and final out in the system class. So we as programmers can use it as System the class name (System.out) out is static object of Printstreem class and println is a method in Printstreem class which are overloaded methods. so we directly write System.out.println(data ). BUT WE SHOULD NOT USE IT ... AS STREAMS ARE DEPENDENT TO THE HARDWARE...Try to use the PrintWriter in the most of the time we are playing with the charectar stream so using Printwriter makes it more independent ,,,PrintWriter out = new PrintWriter(System.out,"true"); Source:

Answered by: mahanth hiremath | Date: 1/28/2010 | Contact mahanth hiremath Contact mahanth hiremath

System is the class and Out is the package and println is the method in java..... Source:

Answered by: subhaja | Date: 2/5/2010 | Contact subhaja Contact subhaja

out is a static inner class of class
System defind in the package java.lang this is why we can write Sy
stem.out without using any instance of class system. println is static method of class out thus we can instiate println without using any instance of class out .thus to call method println method we write
System.out.printn(..). println work
by native method .we write it without importing any package because java.lang package imported automaticaly.. Source:

Answered by: mukesh | Date: 2/5/2010 | Contact mukesh Contact mukesh

System is predefined final class which is defined under a package java.lang, out is a PrintStream object and print is a built-in overloaded method in the out object. Source:

Answered by: Amit Shaw | Date: 2/15/2010 | Contact Amit Shaw Contact Amit Shaw

system is a class and println is a method of PrintStream class and out is an object of PrintStream class. Source:

Answered by: prakash | Date: 4/1/2010 | Contact prakash Contact prakash

system is a class and out is an object and println is a method of Printstreamclass... Source:

Answered by: ram kishore | Date: 4/17/2010 | Contact ram kishore Contact ram kishore

system is a class and out is package and println()is like method and his working show message Source:

Answered by: pawan yadav | Date: 5/29/2010 | Contact pawan yadav Contact pawan yadav

System-final class which is under java.lang.object
out-Object name
println-method Source:

Answered by: Revathi D | Date: 6/8/2010 | Contact Revathi D Contact Revathi D

System is class in java.lang package

out is a static member of type PrinStream class(
declared in the System class.static members of a class can
be accessed directly by classname that's why System.out.

println is a method in PrintStream class.out is of type
PrintStream that's why you access println w.r.t out.

why this big statement? because here no need to import any
package, like you include a header file in c or is the default package.


Answered by: Prakash Ranjan | Date: 6/8/2010 | Contact Prakash Ranjan Contact Prakash Ranjan

system is the class and out is object and println() is a method and this statement display output. Source:

Answered by: richa | Date: 6/22/2010 | Contact richa Contact richa

System is a class in java.lang package and out is a static member of PrintStream class and println or print method first converts the data using the ToString() method. Source:

Answered by: Ankit Kumar | Date: 6/24/2010 | Contact Ankit Kumar Contact Ankit Kumar

May be this is useful to understand

public final class java.lang.System {

public static final out;

// some methods

public class extends.......{

public void println(....){

Answered by: suresh | Date: 6/29/2010 | Contact suresh Contact suresh

actually,System is predefined class found in java.lang package that we have in rt,jar. and println is a function of of printStream class.and out is reference variable. Source:

Answered by: neha | Date: 7/24/2010 | Contact neha Contact neha

System is a class in the java.lang
out is a static variable whose return type is PrintStream defined in the System class.out refers to the outputstream to which the output should go.

class System{
static PrintStream out;

the println() method is defined by the class PrintStream and this method is called on the object returned by System.out.

class Test{
public static void main(String args[]){
PrintStream ob=System.out;
} Source:

Answered by: nikhil kanojia,sit | Date: 8/2/2010 | Contact nikhil kanojia,sit Contact nikhil kanojia,sit

System is a predefined class which helps in to access the system(Computer).
out is an output stream which is by default attached with monitor
and print and println are the methods which are used to display content or data on the monitor Source:

Answered by: Laxman Sadhwani | Date: 8/19/2010 | Contact Laxman Sadhwani Contact Laxman Sadhwani

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