Limpar CMD java

package imput;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

public class imput {
	
	static BufferedReader ir = new BufferedReader(new InputStreamReader(System.in));
	
	static String imput = null;
	static String atual = "main";
	
	public static void main(String[] args) throws IOException {
				
		while(atual.equals("main")){
	
			imput = ir.readLine();
			
			if(imput.equals("clear") || imput.equals("Clear")){
				atual = "clear";
				clear();
	}
	public static void clear() throws IOException{
		try {
            	final String os = System.getProperty("os.name");

                    if (os.contains("Windows")){
                    	Runtime.getRuntime().exec("cls");
                    } else {
                    	Runtime.getRuntime().exec("clear");
                    }
            } catch (final Exception ex) {
           		//  aqui você coloca sua exceção
            }
		atual = "main";
		main(null);
	}
}