mongodb java代码模糊查询

DBCollection coll = db.getCollection("auth_user");
DBObject doc = new BasicDBObject();

String name = "张";
//利用正则表达式模糊查询 不区分大小写
Pattern pattern = Pattern.compile(name + "++", Pattern.CASE_INSENSITIVE);
doc.put("user_name", pattern);

DBCursor cursor = coll.find(doc);