jquery easyui异步树实现代码

/**
* tree
*/
@RequestMapping(value = "/tree.do")
public void mytree(HttpServletResponse response, String id) {
this.writeJson(response, bookService.getChildrenTree(id));
}

@Transactional
@Override
public List<Tree> getChildrenTree(String pid) {
try {
List<Tree> result = new ArrayList<Tree>();
//获得儿子节点的列表
List<TBookType> childrenList = this.getChildrenType(pid);
if (childrenList != null && childrenList.size() > 0) {
for (TBookType child : childrenList) {
// 获取孙子的个数
long count = bookDao.getChildrenCount(String.valueOf(child.getId()));
Tree node = new Tree();
node.setId(String.valueOf(child.getId()));
node.setPid(String.valueOf(child.getPid()));
node.setText(child.getName());
node.setChildren(null);
node.setState(count > 0 ? "closed" : "open");
//将儿子列表childrenList数据逐个存到树当中
result.add(node);
}
}
return result;
} catch (Exception e) {
throw new BusinessException("获取图书类型数据出现错误！", e);
}
}

@Override
public List<TBookType> getChildrenType(String pid) {
//这个的pid就是当前展开节点的id , 通过父节点的 id 来获得子节点
StringBuilder sqlstr = new StringBuilder();
if (StringUtils.isBlank(pid))
sqlstr.append("select * from booktype bt where bt.pid=0");
else
sqlstr.append("select * from booktype bt where bt.pid=" + pid );
return this.search2(TBookType.class, sqlstr.toString());
}

@Override
public long getChildrenCount(String pid) {
//这个的pid就是当前展开节点的id , 通过父节点的 id 来获得子节点的个数
StringBuilder sqlstr = new StringBuilder();
if (StringUtils.isBlank(pid))
sqlstr.append("select count(*) from booktype tb where tb.pid='0'");
else
sqlstr.append("select count(*) from booktype tb where tb.pid='" + pid + "'");
return this.count(sqlstr.toString());
}