ComboBox AutoComplete Java Swing

AutoComboBox.java

import java.util.Vector;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JTextField;

public class AutoComboBox extends JComboBox<Object> {
    
    // default item list
    String keyWord[] = {"item1", "item2", "item3"};
    
    Vector myVector = new Vector();

    public AutoComboBox() {

        setModel(new DefaultComboBoxModel(myVector));
        setSelectedIndex(-1);
        setEditable(true);
        JTextField text = (JTextField) this.getEditor().getEditorComponent();
        text.setFocusable(true);
        text.setText("");
        text.addKeyListener(new ComboListener(this, myVector));
        setMyVector();
    }

    /**
     * set the item list of the AutoComboBox
     * @param keyWord An String array
     */
    public void setKeyWord(String[] keyWord) {
        this.keyWord = keyWord;
        setMyVectorInitial();
    }

    private void setMyVector() {
        int a;
        for (a = 0; a < keyWord.length; a++) {
            myVector.add(keyWord[a]);
        }
    }

    private void setMyVectorInitial() {
        myVector.clear();
        int a;
        for (a = 0; a < keyWord.length; a++) {

            myVector.add(keyWord[a]);
        }
    }

}

ComboListener.java

import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.util.Locale;
import java.util.Vector;
import javax.swing.DefaultComboBoxModel;
import javax.swing.JComboBox;
import javax.swing.JTextField;
import org.apache.commons.lang3.text.WordUtils;

public class ComboListener extends KeyAdapter
{
	@SuppressWarnings("rawtypes")
	JComboBox cbListener;
    @SuppressWarnings("rawtypes")
	Vector vector;
	
	@SuppressWarnings("rawtypes")
	public ComboListener(JComboBox cbListenerParam, Vector vectorParam)
	{
		cbListener = cbListenerParam;
		vector = vectorParam;
	}
	
	@SuppressWarnings({ "unchecked", "rawtypes" })
	public void keyReleased(KeyEvent key)
	{
				// TODO Auto-generated method stub
				String text = ((JTextField)key.getSource()).getText();
 
				cbListener.setModel(new DefaultComboBoxModel(getFilteredList(text)));
				cbListener.setSelectedIndex(-1);
				((JTextField)cbListener.getEditor().getEditorComponent()).setText(text);
				cbListener.showPopup();
	}
	
	
	@SuppressWarnings({ "rawtypes", "unchecked" })
	public Vector getFilteredList(String text)
	{
		Vector v = new Vector();
		for(int a = 0;a<vector.size();a++)
		{
			if(vector.get(a).toString().startsWith(text))
			{
				v.add(vector.get(a).toString());
			}
                        else if(vector.get(a).toString().startsWith(text.toLowerCase()))
			{
				v.add(vector.get(a).toString());
			}
                         else if(vector.get(a).toString().startsWith(text.toUpperCase()))
			{
				v.add(vector.get(a).toString());
			}
                         else if(vector.get(a).toString().startsWith(WordUtils.capitalizeFully(text)))
			{
				v.add(vector.get(a).toString());
			}
                         else if(vector.get(a).toString().startsWith(WordUtils.uncapitalize(text)))
			{
				v.add(vector.get(a).toString());
			}
		}
		return v;
	}
}

Though the typing text is upper Case, lowercase or Title case the result will loaded.