My Java Tips

Taking input from keyboard involves various steps. Lot of people ask for some ready made class which will serve the purpose. Following class is a good choice. You can use "readInt()", "readDouble()", "readChar()" and "readString()" methods according to your needs.

---

Java Code:

import java.io.*;

public class KeyboardInput {

	static BufferedReader stdin =
		new BufferedReader( new InputStreamReader(System.in));

	public static int readInt () {
		while (true) {
			try{
				String line = stdin.readLine();
				int value = Integer.parseInt(line);
				return value;
			} catch(java.lang.NumberFormatException e){
				;
			} catch(IOException e){
				;
			}
		}
	} // end readInt ()

	public static int readInt (String text) {
		System.out.print(text);
		while (true) {
			try{
				String line = stdin.readLine();
				int value = Integer.parseInt(line);
				return value;
			} catch(java.lang.NumberFormatException e){
				;
			} catch(IOException e){
				;
			}
		}
	} // end readInt (String text)

	public static double readDouble () {
		while (true) {
			try {
				String line = stdin.readLine();
				double value = Double.valueOf(line).doubleValue();
				return value;
			} catch (java.lang.NumberFormatException e){
				;
			} catch (IOException e){
				;
			}
		}
	} // end readDouble()

	public static char readChar () {
		while (true) {
			try {
				String line = stdin.readLine();
				char value = line.charAt(0);
				return value;
			} catch (IOException e){
				;
			}
		}
	} // end readChar()

	public static String readString (){
		while(true) {
			try {
				return stdin.readLine();
			} catch (IOException e) {
				;
			}
		}
	} // end readString()

	public static String readString (String text){
		System.out.print(text);
		while(true) {
			try {
				return stdin.readLine();
			} catch (IOException e) {
				;
			}
		}
	} // end readString(String text)

}

Usage example:

Java Code:

       	    char choice = KeyboardInput.readChar();