如何使用java更新mongodb Collection的子文档

Question

如何使用JAVA

更新某些json文件的ptconfig

{
  "_id" : "1",
  "name" : "kiran",
  "status" : "online",
  "description" : "process 1",
  "ptConfig" : {
      "xms" : 232,
      "xmx" : 233
  }
}