Java Program for Writing Console Output

How to write console output?

print and println methods in System.out are mostly used for console output.
These methods are defined by the class PrintStream which is the type of object referenced by System.out. System.out is the byte stream.
PrintStream is the output derived from OutputStream. write method is also defined in PrintStream for console output.

void write(int byteval)

//Java code to Write a character in Console Output                              
import java.io.*;                                                               
                                                                                
class WriteCharacterTest {                                                      
 public static void main(String args[]) {                                       
  int byteval;                                                                  
  byteval = 'J';                                                                
                                                                                
  System.out.write(byteval);                                                    
  System.out.write('\n');                                                       
 }                                                                              
}    

Output:

$javac WriteCharacterTest.java
$java WriteCharacterTest
J

Is there any alternate to print console output?

Using PrintWriter Class:

For real world programs, recommended method to write to the console in java is through a PrintWriter Stream.
PrintWriter is one of the character based classes for console output in java.
PrintWriter defines several constructer, below is one of them.

PrintWriter(OutputStream outputStream, boolean flushOnNewline)

here outputStream is an object of OutputStream, and flushOnNewline is true to ensure whether java flushes the output every time a println() method is invoked. otherwise no flushing.

//Java code to Write Console Output using PrintWriter class                     
import java.io.*;                                                               
                                                                                
class PrintWriterTest {                                                         
 public static void main(String args[]) {                                       
  PrintWriter pw = new PrintWriter(System.out, true);                           
  pw.println("PrintWriter class demo");                                         
  pw.println(100);                                                              
  pw.println(-4.67);                                                            
 }                                                                              
} 

Output:

PrintWriter class demo
100
-4.67

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