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Oracle Certified Professional: Java SE Developer 1Z0-831 (Java SE 25) · Domain 5: Working with arrays and collections

List, Set, Map, Queue and Deque interfaces and their main implementations

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Last reviewed September 25, 2026 · Leer en español

The Java Collections Framework is a set of interfaces and implementations in java.util. Collection is the root interface for List, Set and Queue (and Deque, which extends Queue). Map is part of the framework but does not extend Collection, because it stores key-value pairs rather than single elements. You usually declare variables with the interface type, List<String> names = new ArrayList<>();, so you can switch implementations later.

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