Dinup Kandel Dinup Kandel - 1 year ago 151
Java Question

What is System, out, println in System.out.println() in Java

Possible Duplicate:

What's the meaning of System.out.println in Java?

I was looking for the answer of what
are in
in the Java. I searched and found a different answer like these:

  • System is a built-in class present in java.lang package.
    This class has a final modifier, which means that, it cannot be inherited by other classes.
    It contains pre-defined methods and fields, which provides facilities like standard input, output, etc.

  • out is a static final field (ie, variable)in System class which is of the type PrintStream (a built-in class, contains methods to print the different data values).
    static fields and methods must be accessed by using the class name, so ( System.out ).

  • out here denotes the reference variable of the type PrintStream class.

  • println() is a public method in PrintStream class to print the data values.
    Hence to access a method in PrintStream class, we use out.println() (as non static methods and fields can only be accessed by using the refrence varialble)

In another page i find another contrasting definition as

System.out.print is a standard output function used in java. where System specifies the package name, out specifies the class name and print is a function in that class.

I am confused by these. Could anybody please exactly tell me what they are?

pap pap
Answer Source

The first answer you posted (System is a built-in class...) is pretty spot on.

You can add that the System class contains large portions which are native and that is set up by the JVM during startup, like connecting the System.out printstream to the native output stream associated with the "standard out" (console).

Recommended from our users: Dynamic Network Monitoring from WhatsUp Gold from IPSwitch. Free Download