조립 트 리 구조 데이터 기능 패키지

 /**
     *         
     * @param
     * @return
     */
    public static  List buildTree(List list) throws InvocationTargetException, IllegalAccessException, NoSuchMethodException, IntrospectionException {
        List trees = new ArrayList<>();
        for (T treeNode : list) {
            Method method = treeNode.getClass().getDeclaredMethod("getParentId", null);
            Object value = method.invoke(treeNode, null);
            if ("0".equals(String.valueOf(value))) {
                trees.add(findChildren(treeNode,list));
            }
        }
        return trees;
    }

 public static  T findChildren(T t,List treeNodes) throws NoSuchMethodException, InvocationTargetException, IllegalAccessException, IntrospectionException {
        Method getIdMethod = t.getClass().getDeclaredMethod("getId");
        String id = String.valueOf(getIdMethod.invoke(t, null));
        for (T it : treeNodes) {
            Method getParentIdMethod = it.getClass().getDeclaredMethod("getParentId");
            Object parentId = getParentIdMethod.invoke(it, null);
            if (id.equals(String.valueOf(parentId))) {
                Method getChildrenMethod = t.getClass().getDeclaredMethod("getChildren");
                Object children = getChildrenMethod.invoke(t, null);
                if (null == children ) {
                    Method setChildrenMethod = t.getClass().getDeclaredMethod("setChildren",HashSet.class);
                    setChildrenMethod.invoke(t, new HashSet());
                }
                ((HashSet)getChildrenMethod.invoke(t, null)).add(findChildren(it, treeNodes));
            }

        }
        return t;
    }