Identify and Fix Deprecated Calls
IntelliJ IDEA will warn you if you're using deprecated methods, and they will be shown with a strikethrough if they're marked for removal.
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IntelliJ IDEA shows deprecated methods that are marked for removal with a red strikethrough. JDK 16 has marked the wrapper class constructors for removal, so you'll see these with a red strikethrough in IntelliJ IDEA.