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Practice

Contract Lab

⭐⭐ intermediate~35 min of coding3 challenges

Build value classes with correct equals/hashCode, seal leaky APIs, and defeat the Integer-cache trap.

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What you will practice

  1. Write the equals/hashCode Pair⭐⭐ intermediate
  2. Find the Leaked Mutability⭐⭐ intermediate
  3. Predict the Box Comparison⭐⭐ intermediate

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