System.out is the object of java.io.PrintStream class. And it’s capable enough to send any kind of data to console or File. So in most of the case we don’t go for any other option. But still as a part of “Various ways to write on console”, we gonna discuss several method of writing data on console/command prompt. You can see the list of methods here.

PrintStream – System.out

import java.util.*;
class SODemo
{
	public static void main(String[] s)
	{
		System.out.println(1);  // println(int)
		System.out.println(1.2f);  // println(float)
		System.out.println(1.2);  // println(double)
		System.out.println("Ankit");  // println(String)
		System.out.println('c');  // println(char)
		System.out.println(new Date());  // println(Object)
		System.out.println(new myOPClass(9));  // println(Object)	
	}
}

class myOPClass
{
	int x = 0;
	myOPClass(int x)
	{
		this.x = x;	
	}
	public String toString()
	{
		return "Value of X: "+x;	
	}	
}

Output:

Note: PrintStream is derived from OutputStream class of java.io package. PrintStream is a Filtered Output Stream.

OutputStream + System.out

As discussed, OutputStream is the parent class of PrintStream. So a object of PrintStream class can be referenced by OutputStream.

import java.io.*;
class OSDemo
{
	public static void main(String[] s)throws Exception
	{
		String str = "I wanna print this!";
		byte[] b = str.getBytes();
		
		OutputStream os = System.out;
		os.write(b);
	}
}

Output:

OutputStreamWriter + System.out

import java.io.*;
class OSWDemo
{
	public static void main(String[] s)throws Exception
	{
		String str = "I wanna print this!";
		
		OutputStream os = System.out;
		OutputStreamWriter osw = new OutputStreamWriter(os);
		
		osw.write("Ankit Virparia\n\n");
		osw.flush();
		
		osw.write(str, 2,11);
		osw.flush();
		
		
	}
}

Output:

BufferedWriter + OutputStreamWriter + System.out

import java.io.*;
class BufferedWriterDemo
{
	public static void main(String[] s)throws Exception
	{
		String str = "I wanna print this!";
		
		OutputStream os = System.out;
		OutputStreamWriter osw = new OutputStreamWriter(os);
		BufferedWriter bw = new BufferedWriter(osw);
		
		bw.write("Ankit Virparia\n\n");
		bw.flush();
		
		bw.write(str, 2,11);
		bw.flush();		
	}
}

Output:

Console

import java.io.*;
class ConsoleWriteDemo
{
	public static void main(String[] s)
	{
		Console con = System.console();
		PrintWriter ps = con.writer();
		ps.print("Good Morning!");
		ps.println();
		
		con.writer().println("Hi"); 
	}
}

Output:

The post Various ways to write on Console appeared first on Ankit Virparia.

InputStream – System.in

class ISDemo
{
	public static void main(String[] s)throws Exception
	{
		byte[] b = new byte[1024];
		System.out.print("Enter Text:");
		int cnt = System.in.read(b);	
		String userString = new String(b,0,cnt);
		System.out.println("No. of chars: "+cnt);
		System.out.println("String: "+userString);
	}	
}

Output:

InputStreamReader + Systen.in

import java.io.*;
class ISRDemo
{
	public static void main(String[] s)throws Exception
	{
		InputStreamReader isr = new InputStreamReader(System.in);
		int data;
		String str = "";
		char c ;
		while(true)
		{
			data = isr.read();
			c = (char)data;
			if(c=='\n')break;
			str += c;
		}
		
		System.out.println("String: "+str);
	}	
}

Output:

BufferedReader + InputStreamReader + Systen.in

import java.io.*;

class BufferedReaderDemo
{
	public static void main(String[] arg)throws Exception
	{
		BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
		System.out.print("Enter text:");
		String str = br.readLine();
		System.out.println("String: "+str);	
	}
}

Output:

Console

import java.io.*;
class ConsoleDemo
{
	public static void main(String[] s)
	{
		Console con = System.console();
		System.out.print("Enter String:");
		String str = con.readLine();
		System.out.println("String: "+str); 
	}
}

Output:

Scanner

import java.util.*;

class ScannerDemo
{
	public static void main(String[] arg)
	{
		Scanner sc = new Scanner(System.in);
		System.out.print("Enter text:");
		String str = sc.nextLine();
		System.out.println("String: "+str);	
	}
}

Output:

The post Various ways to read from Console appeared first on Ankit Virparia.