System.out.println();

[Ritesh raushan]

whats is the internal coding of System.out.println();how is it works....i saw a coding in System class

class System
{
public static final PrintStream out=null;
}


but i did'nt undestand...this is has-A relationship but where the object of PrintStream class is creating.
please help me......thanks

[Campbell Ritchie]

You shouldn’t care what the internal coding is, but if you insist:-

1: Find the src.zip file in your Java installation folder.

2: Unzip it.

3: Navigate to the ja‍va folder

4: Navigate to the lang folder

5: Read the System.java file

If you need the JVM code, you can download it too, but I can’t remember whence.

[Guillaume Jourdan]

Hello,

System.out.println()

out => PrintStream

PrintStream => pirntln method invoke print method => Javadoc PrintStream println(java.lang.String)

docs.oracle.com wrote: public void print(String s)
Print a string. If the argument is null then the string "null" is printed. Otherwise, the string's characters are converted into bytes according to the platform's default character encoding, and these bytes are written in exactly the manner of the write(int) method.
Parameters:
s - The String to be printed

Javadoc PrintStream print(java.lang.String)

If you want an implementation, you can extract the code in open-jdk :

open-jdk source

[Vishal Shaw]

Ritesh raushan wrote:but i did'nt undestand...this is has-A relationship but where the object of PrintStream class is creating.

What is there, you did not understand? It simply says that the System class has an object "out" of PrintStream class. You have already shown the code there. If you are worried about the initialization of "out",then

public static void setOut(PrintStream out) {
	checkIO();
	setOut0(out);
    }

shows you how "out" is reassigned

Cheers