Darcula/src/com/bulenkov/darcula/util/UIUtil.java

package com.bulenkov.darcula.util;

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

/**
 * @author Konstantin Bulenkov
 */
public class UIUtil {
  public static <T extends JComponent> T findComponentOfType(JComponent parent, Class<T> cls) {
    if (parent == null || cls.isAssignableFrom(parent.getClass())) {
      @SuppressWarnings({"unchecked"}) final T t = (T)parent;
      return t;
    }
    for (Component component : parent.getComponents()) {
      if (component instanceof JComponent) {
        T comp = findComponentOfType((JComponent)component, cls);
        if (comp != null) return comp;
      }
    }
    return null;
  }

  public static <T> T getParentOfType(Class<? extends T> cls, Component c) {
    Component eachParent = c;
    while (eachParent != null) {
      if (cls.isAssignableFrom(eachParent.getClass())) {
        @SuppressWarnings({"unchecked"}) final T t = (T)eachParent;
        return t;
      }

      eachParent = eachParent.getParent();
    }

    return null;
  }


}