Accepting only letters and spaces in JTextField

public class AlphaDocument extends PlainDocument {

      public AlphaDocument(){
            super();
      }
      
      public void insertString(int offset, String s, AttributeSet attributeSet)
             throws BadLocationException{
             
             char[] inputChars = s.toCharArray();
             try{
                    for(int i = 0; i < inputChars.length; i++){
                        if(Character.isLetter(inputChars[i]) || inputChars[i] == ' '){
                              super.insertString(offset, s, attributeSet);
                        }
                        else{
                              Toolkit.getDefaultToolkit().beep();
                        }

                    }

                          
             }
             catch (Exception ex){
                    Toolkit.getDefaultToolkit().beep();
             }

      }

}

this works, but not when pasting a string into the text field.  also, how can i optionally limit the text length?
abstractionzAsked:
Who is Participating?
 
objectsConnect With a Mentor Commented:
It is, sorry didn't look at that closely.

you problem there is in your test:

if(success && limit == 0 || this.getLength() + s.length() <= limit){

should be:

if(success && (limit == 0 || this.getLength() + s.length() <= limit)){
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abstractionzAuthor Commented:
public class AlphaDocument extends PlainDocument {
      
      private int limit = 0;
      
      public AlphaDocument(){
            super();
      }
      
      public AlphaDocument(int limit){
            super();
            this.limit = limit;
      }
      
      public void insertString(int offset, String s, AttributeSet attributeSet)
             throws BadLocationException{
             char[] inputChars = s.toCharArray();
             boolean success = false;
             try{
                    for(int i = 0; i < inputChars.length; i++){
                        if(Character.isLetter(inputChars[i]) || inputChars[i] == ' '){
                              success = true;
                        }
                        else{
                              success = false;
                              break;
                        }
                    }
                    
                    if(success && limit == 0 || this.getLength() + s.length() <= limit){
                        super.insertString(offset, s, attributeSet);
                    }
                    else{
                        Toolkit.getDefaultToolkit().beep();
                    }
                          
             }
             catch (Exception ex){
                    Toolkit.getDefaultToolkit().beep();
             }

      }

}

this works fine until i enter a limit for the text, then it allows numbers.
0
 
maheshexpCommented:
Customized fields can easily be created by extending the model and changing the default model provided. For example, the following piece of code will create a field that holds only upper case characters. It will work even if text is pasted into from the clipboard or it is altered via programmatic changes.



 public class UpperCaseField extends JTextField {
 
     public UpperCaseField(int cols) {
         super(cols);
     }
 
     protected Document createDefaultModel() {
             return new UpperCaseDocument();
     }
 
     static class UpperCaseDocument extends PlainDocument {
 
         public void insertString(int offs, String str, AttributeSet a)
                 throws BadLocationException {
 
                 if (str == null) {
                   return;
                 }
                 char[] upper = str.toCharArray();
                 for (int i = 0; i < upper.length; i++) {
                   upper[i] = Character.toUpperCase(upper[i]);
                 }
                 super.insertString(offs, new String(upper), a);
             }
     }
 }

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maheshexpCommented:
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0
 
twobitadderCommented:
it's also in page16.htm
0
 
maheshexpCommented:
twobitadder, very much thanks for the info...yeah i didn't know abt it...i will remove it...
0
 
abstractionzAuthor Commented:
maheshexp,

thanks for the general information but i already know about formattedtextfields.  i posted my code because there was a bug in it, which i found.  the problem was in the conditional.  i changed it to:

if(success && (limit == 0 || this.getLength() + s.length() <= limit)){
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objectsCommented:
>   super.insertString(offset, s, attributeSet);

you insert the entire string everytime you find a valid char.
Instead you should be only inserting the valid char.

Alternatively you may want to only insert the string if *all* chars are valid.
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abstractionzAuthor Commented:
> Alternatively you may want to only insert the string if *all* chars are valid.

isn't that what i'm doing in my 2nd posting?
0
 
abstractionzAuthor Commented:
yea that's what i realized 4 posts up.  thanks though.
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