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String Immutability in Java

HardTechnical Fundamentals00:00
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Your question is String Immutability in Java. Take a moment with it on the right.

Talk me through your thinking if you like. When you're confident, submit your answer and I'll grade it like a real screen (7/10 or better passes).

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Problem

Describe the concept of String immutability in Java and its implications for performance and security. Explain what immutability means at the API and JVM level, how operations such as concatenation behave, and why immutable strings can be safely shared. Discuss the benefits and limitations for security, including handling passwords or tokens. Scope your answer to standard Java and the JVM, with one concrete code example.