Simple LRU Cache in Java: Explanation & Practice

Problem summary

Implement a cache that removes least recently used item when capacity is exceeded.

Starter code

import java.util.*;

// Use LinkedHashMap with access order

public class Main {
    public static void main(String[] args) {
        // Cache with capacity 3
        // Add items and show eviction
    }
}

Expected output and test cases

• A evicted when D added

  Cache: {B=2, C=3, D=4}

• B evicted, A accessed

  Cache: {A=1, C=3, D=4}

• Single item cache

  Cache: {X=1}

Hints

1. LinkedHashMap with accessOrder=true
2. Override removeEldestEntry()
3. Return true when size > capacity

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