Gwt-ext再帰生成colum treeのJSON

public String getRequirementJson() {
		List<RequirementEntity> requirementRoots = getRootRequirement();
		StringBuffer buff = new StringBuffer();
		StringBuffer b = new StringBuffer();
		// for (RequirementEntity root : requirementRoots) {
		// b.append(recursionFn(root, buff));
		// }
		for (int i = 0; i < requirementRoots.size(); i++) {
			RequirementEntity root = requirementRoots.get(i);
			if (i != requirementRoots.size() - 1) {
				b.append(recursionFn(root, buff));
				b.append(",");
			} else {
				b.append(recursionFn(root, buff));
			}
		}
		return b.toString();
	}

	public JSONObject recursionFn(RequirementEntity root, StringBuffer json) {
		List<RequirementEntity> childList = getChildList(root);
		if (childList.size() > 0) {
			JSONObject jsonObject = new JSONObject();
			jsonObject.put("id", root.getId());
			jsonObject.put("aprvStatus", root.getAprvStatus());
			jsonObject.put("createDt", DateUtil.parseDate(root.getCreateDt(),
					"dd/MM/yyyy"));
			jsonObject.put("createdBy", root.getCreatedBy());
			jsonObject.put("parentId", root.getParentId());
			jsonObject.put("histVer", root.getHistVer());
			jsonObject.put("reqDesc", root.getReqDesc());
			jsonObject.put("reqPriority", root.getReqPriority());
			jsonObject.put("uiProvider", "col");
			jsonObject.put("reqTitle", root.getReqTitle());
			jsonObject.put("iconCls", "task-folder");
			jsonObject.put("updateDt", root.getUpdateDt());
			jsonObject.put("updatedBy", root.getUpdatedBy());

			JSONObject children = new JSONObject();
			List<JSONObject> jsonArray = new ArrayList<JSONObject>();

			for (int i = 0; i < childList.size(); i++) {
				RequirementEntity childEntity = childList.get(i);
				children = recursionFn(childEntity, json);
				jsonArray.add(i, children);
			}
			jsonObject.put("children", jsonArray);
			json.append(jsonObject.toString());
			return jsonObject;
		} else {
			JSONObject jsonObject = new JSONObject();
			jsonObject.put("id", root.getId());
			jsonObject.put("aprvStatus", root.getAprvStatus());
			jsonObject.put("createDt", DateUtil.parseDate(root.getCreateDt(),
					"dd/MM/yyyy"));
			jsonObject.put("createdBy", root.getCreatedBy());
			jsonObject.put("parentId", root.getParentId());
			jsonObject.put("histVer", root.getHistVer());
			jsonObject.put("reqDesc", root.getReqDesc());
			jsonObject.put("reqPriority", root.getReqPriority());
			jsonObject.put("uiProvider", "col");
			jsonObject.put("reqTitle", root.getReqTitle());
			jsonObject.put("iconCls", "task");
			jsonObject.put("updateDt", root.getUpdateDt());
			jsonObject.put("updatedBy", root.getUpdatedBy());
			jsonObject.put("leaf", true);
			json.append(jsonObject.toString());
			return jsonObject;
		}
	}

	public List<RequirementEntity> getChildList(RequirementEntity nodeEntity) {
		List<RequirementEntity> childList = requirementDAO
				.findByParentId(nodeEntity.getId());
		return childList;
	}

Gwt-extはColumnTreeのJSONを再帰的に生成し,方法は最適化される必要がある.
 
JSONが生産に成功し、ページが何度も表示されない原因:JSONで追加を忘れた

jsonObject.put("uiProvider", "col");