Java Coding Problem - Merchant Feature Flag Analytics

Context

You are working on a payments platform that supports thousands of merchants.
For each merchant, we can enable or disable a set of product features — such as:

• INSTANT_PAYOUTS

• MULTI_CURRENCY

• FRAUD_PROTECTION

• BETA_DASHBOARD

• ADVANCED_REPORTING

The platform stores feature flags per merchant in a database table:

merchant_id | feature_name        | enabled
---------------------------------------------
M101        | INSTANT_PAYOUTS     | 1
M101        | FRAUD_PROTECTION    | 0
M101        | MULTI_CURRENCY      | 1
M101        | BETA_DASHBOARD      | 1
M102        | INSTANT_PAYOUTS     | 0
...

Where:

• enabled = 1 → feature is active

• enabled = 0 → feature is inactive

Your task is to build logic that helps the platform understand how many features each merchant has enabled vs disabled.

For a given merchant_id, compute:

1. Total number of enabled features

2. Total number of disabled features

3. (Optional) Return a summary object with the counts

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Input

You are given:

class FeatureFlag {
    String merchantId;
    String featureName;
    int enabled; // 1 or 0
}

And a method:

List<FeatureFlag> getFeatureFlagsForMerchant(String merchantId);

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Output

Design a method:

FeatureFlagSummary summarize(String merchantId);

Where:

record FeatureFlagSummary(
    String merchantId,
    int enabledCount,
    int disabledCount
) {}

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Requirements

• Count how many feature flags for the merchant have enabled = 1

• Count how many feature flags have enabled = 0

• Return these counts in a summary object

---

Example

Input:

Merchant M101 has flags:

[1, 0, 1, 1]

Output:

{
  merchantId: “M101”,
  enabledCount: 3,
  disabledCount: 1
}

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Solution