/*
 * Copyright 2010 JBoss Inc
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.drools.eclipse.rulebuilder.ui;

import org.eclipse.swt.events.KeyEvent;
import org.eclipse.swt.events.KeyListener;
import org.eclipse.swt.widgets.Text;

public class NumericKeyFilter implements KeyListener {

    private Text box;

    public NumericKeyFilter(Text box){
        this.box = box;
        box.addKeyListener(this);
    }

    public void keyPressed(KeyEvent e) {
        char c = e.character;
        if (Character.isLetter( c ) && c != '='
            && !(this.box.getText().startsWith( "=" ))) {
            e.doit = false;
        }
    }

    public void keyReleased(KeyEvent e) {

    }

}
