import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JTextField;
import javax.swing.KeyStroke;
public class Main {
public static void main(String[] argv) {
JTextField component = new JTextField(10);
component.getInputMap(JComponent.WHEN_FOCUSED).put(KeyStroke.getKeyStroke(new Character(' '), 0), "actionName");
JFrame f = new JFrame();
f.add(component);
f.setSize(300, 300);
f.setVisible(true);
}
}