Instructions

Create a simple server that uses simple design patterns written in JAVA

• Singleton: Wrap your main server instance as a singleton class

• Factory: Your server should parse the routes and create a new Processor class depending on the route

• Builder: The process method of your Processor should use the Builder pattern to create a response.

• Lazy Loading: Lazy load users data on the first fetch.

Final response should be converted to Json

First parse url, then use factory to instantiate correct Processor class.

Processor Class

• Has a process() method that returns a Response object

• Add a subclass per endpoint

• Takes a hashmap of key value args

• User a factory to create these, based on the endpoint

Response Class

• This class gets stringified

• Needs a ResponseBuilder helper

• Needs Date

• Needs Params Map (String, String)

• Needs response (Object, use Integer for ints)

• Needs Response Code (String)

Server Class

• Wrap simple server as a singleton, and give it a method

  • getInstance()

  • then run() to start

Endpoints

• /math/add?a=&b=

  • return a + b

• /math/add?a=

  • return a + 1

• /posts?userid=

  • Single post

• /users?userid=

  • Single userId

• All others return the string ERROR as the response code.

Return Format

You will need a response class that looks like this before passing to JSON.

"{

"date": "2019-02-10T20:40:59.257Z", // time that this was generated

"params": {

"a": 2

},

responseCode: OK

"response": 3,

}"

Data.json file

{ "users":[ { "username" : "rey", "userid" : 0, "myKey" : "myValue" }, { "username" : "lukeSkywalker", "userid" : 1 }, { "username" : "daenerysStormborn", "userid" : 2 }, { "username" : "khalDrogo", "userid" : 3 } ], "posts":[ { "postid":0, "userid": 1, "data": "I lost my lightsaber, anyone seen it?" }, { "postid":1, "userid": 0, "data": "Found lightsaber, looking for owner" }, { "postid":3, "userid": 1, "data": "Guess How many dragons I have" } ], "comments":[ { "postid":0, "userid": 1, "data": "I think I found it!" }, { "postid":0, "userid": 0, "data": "Wow thanks, maybe you can be a Jedi now!" }, { "postid":2, "userid": 0, "data": "None?" }, { "postid":2, "userid": 3, "data": "8?" } ] }