Archief - JAVA alleen letters ingeven

public static void main(String[] args)
        {
               Scanner input = new Scanner(System.in); 
               boolean geldig = false;
               String test=null;
               
 			   while (! geldig)
 		       { 	
 				   int teller=0;
 				    System.out.print("geef naam in: ");
 		            System.out.flush(); 
 		             
 		            	  test = input.next();
 		            	  for(int i=0; i<test.length(); i++)
 		                  {
 		                       
	 		                
	 		        	    if(Character.isLetter(test.charAt(i)))
	 		        	    {
	 		        		  teller++;
	 		        	    }
	 		        	  
 		                  }
 		            	  
 		            	  System.out.print(teller+"\n"+test.length()+"\n");
	 		        	  if( teller == test.length())
	 		        	  {
	 		        		  geldig = true; // uit de lus! 
	 		        	  }
	 		        	  else
	 		        	  {
	 		        		 System.out.println("Je mag alleen een letters ingeven!");
	 		        		 input.nextLine();
	 		        	  }
 		        	
                
 		       }

public static void main(String[] args)
{
	Scanner input = new Scanner(System.in);
	boolean geldig = true;
	String test=null;

	while (true)
	{
		System.out.print("geef naam in: ");
		System.out.flush();

		test = input.next();
		
		for (int i = 0; i < test.length(); i++)
		{
			if(!Character.isLetter(test.charAt(i)))
			{
				geldig = false;
				break;
			}
		}

		if (geldig) return;
		
		System.out.println("Je mag alleen een letters ingeven!");
		input.nextLine();
	}
}

public void test(String str) {

        char[] chr = str.toCharArray();
        int i = 0;
        boolean found = false;
        while ( i < chr.length && !found)
        {
           char c = chr[i];
           if((c < 'A' || c > 'Z') && (c < 'a' || c >'z'))
           {
                System.out.println("enkel letters");
                found = true;
           }
           i++;
        }        
    }

 public boolean hasNumber(String s) {
  for (int j = 0;j < s.length();j++) {
    if (!Character.isLetter(s.charAt(j))) {
      return false;
    }
  }
  return true;
}

 boolean bevat = false ;
        for (int j = 0;j < s.length() && bevat == false;j++) {
            if (! Character.isLetter(s.charAt(j))) {
                bevat = true ;
            }
        }
        return bevat ;

mport java.util.regex.Matcher;  
import java.util.regex.Pattern;  
 
  public class lykmeraidisdecoolste{  
    public static boolean isLetters(String str){  
         boolean isValid = false;  
         
           String expression = "Hier komt uw regex";  
           CharSequence inputStr = str;  
           Pattern pattern = Pattern.compile(expression);  
           Matcher matcher = pattern.matcher(inputStr);  
           if(matcher.matches()){  
              isValid = true;  
           }  
           return isValid;  
         }  
      }