Flashcards

Flashcard Study

Java: Iteration and Traversal

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Why might an Iterator be preferred for safe removal during iteration?

It allows safe removal of elements without causing ConcurrentModificationException. Using an Iterator to remove elements during iteration prevents…

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Flashcard Study

Java: Iteration and Traversal

Front

How would you explain an enhanced for loop in a Java interview?

A simplified iteration construct for collections and arrays. The enhanced for loop, introduced in Java 5, allows straightforward…

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Flashcard Study

Java: Iteration and Traversal

Front

When do you need an `Iterator` instead of only an enhanced for-loop?

When you must remove elements safely during traversal. Enhanced for-loops are great for simple reads, but iterators matter…

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Java: equals and hashCode in Collections

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Why do `HashSet` and `HashMap` care about `equals` and `hashCode`?

They use those methods to decide sameness and where items belong internally. Hash-based collections do not know your…

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Flashcard Study

Java: Collection Performance Basics

Front

Reading and understanding Java Collections code?

Focus on collection type, operations, and intended use. When reading Java Collections code, identify the type of collection…

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Flashcard Study

Java: Collection Performance Basics

Front

Designing collections for catalogs?

Choose based on operation needs and element characteristics. Designing collections requires understanding operation needs (e.g., frequent updates, reads)…

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Flashcard Study

Java: Collection Performance Basics

Front

HashSet vs. ArrayList performance?

HashSet offers unique, faster lookups; ArrayList allows duplicates and ordering. HashSet is optimized for scenarios requiring unique elements…

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Flashcard Study

Java: Collection Performance Basics

Front

Benefits of using HashMap?

HashMap offers fast, constant time operations. HashMap's strength is its ability to perform operations like put, get, and…

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Flashcard Study

Java: Collection Performance Basics

Front

Common pitfalls with ArrayList?

Misusing its dynamic sizing can lead to inefficiency. While ArrayList automatically resizes, frequent resizing can cause performance issues.…

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Flashcard Study

Java: Collection Performance Basics

Front

Choosing between HashSet and TreeSet?

HashSet is faster, TreeSet maintains order. HashSet offers faster operations (average O(1)) because it uses hashing, while TreeSet…

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