customtextfield.java

Typing fingers Typing programme

import java.awt.*;
import javax.swing.*;
import javax.swing.text.*;

/**	This class extends JTextField to provide the options of only alphabetic, numeric data.
*/

public class CustomTextField extends JTextField {
	private int type;
	public CustomTextField(int cols) {
		super(cols);
	}
	public CustomTextField(int cols,int type){
		super(cols);
		this.type=type;
	}
	public CustomTextField(){
		type=Utilities.ALPHABETIC;
	}
	protected Document createDefaultModel() {
		return new DiscardChars(type);
	}
}
class DiscardChars extends PlainDocument {

	private int type;
	DiscardChars(int type){
		this.type=type;
	}

	public void insertString(int offs, String str, AttributeSet a) 
		throws BadLocationException {

		if (str == null) {
			return;
		}
		char[] chars = str.toCharArray();

		chars=selectChars(chars);
	 
		super.insertString(offs, new String(chars), a);
	}
	private char[] selectChars(char [] ch){
		int j=0,i=0;
		String temp="";
		if(type==0)
			for(;i<ch.length;i++)
				if((ch[i]>=65&&ch[i]<=90)||(ch[i]>=97&&ch[i]<=122)||ch[i]==8||ch[i]==32)
					temp=temp+ch[i];

		else if(type==1)
			for(;i<ch.length;i++)
				if(ch[i]>=48&&ch[i]<=57||ch[i]==8||ch[i]==32)
					temp=temp+ch[i];	
		else 
			temp=new String(ch);
		return temp.toCharArray();
	}
}