Your solution to this coding test will be evaluated based on its:

• Adherence to best coding practices
  • Add unit tests that cover the basic features of TransactionDataFetcher. One test per method would be enough
• Correctness
• Efficiency

Take your time to fully understand the problem and formulate a plan before starting to code, and don't hesitate to ask any questions if you have doubts.

Since we are a money transfer company this test will revolve around a (very) simplified transaction model. Our aim is to implement the methods listed in com.smallworld.TransactionDataFetcher, a component that allows us to get some insight into the transactions our system has.

A battery of test transactions is stored in transactions.json that is going to be used as a datasource for all our data mapping needs.

Each entry in transactions.json consists of:

• mtn: unique identifier of the transaction
• amount
• senderFullName, senderAge: sender information
• beneficiaryFullName, beneficiaryAge: beneficiary information
• issueId, issueSolved, issueMessage: issue information. Transactions can:
  • Contain no issues: in this case, issueId = null.
  • Contain a list of issues: in this case, the transaction information will be repeated in different entries in transactions.json changing the issue related information.

You can think of the json as the output of an SQL query joining transaction with transaction_issue, so the following example would represent a unique transaction with 2 issues:

{
    "mtn": 1284564,
    "amount": 150.2,
    "senderFullName": "Tom Shelby",
    "senderAge": 22,
    "beneficiaryFullName": "Arthur Shelby",
    "beneficiaryAge": 60,
    "issueId": 2,
    "issueSolved": true,
    "issueMessage": "Never gonna give you up"
  },
  {
    "mtn": 1284564,
    "amount": 150.2,
    "senderFullName": "Tom Shelby",
    "senderAge": 22,
    "beneficiaryFullName": "Arthur Shelby",
    "beneficiaryAge": 60,
    "issueId": 3,
    "issueSolved": false,
    "issueMessage": "Looks like money laundering"
  }

Each method to be implemented includes a brief description of what's expected of it.

The parameters and return types of each method can be modified to fit the model that contains the transaction information

Have fun!