What is a raw type and why shouldn't we use it?
Generics provide type safety in Java, while raw types circumvent it. Avoid raw types to prevent potential ClassCastException.
Use generics correctly as follows:
Incorrect raw type usage:
Generics confirm that only Strings will be added, hence eliminating the need for casting.
Unmasking raw types: an unnecessary relic
Raw types represent a relic from Java's prehistoric era before the introduction of Java 5, when generics were not part of the language. They denote a class or interface without type parameter(s), thereby bypassing the type safety.
Type Safety: Catch errors before they catch you
Parameterized types (List<Integer> for example) allow the compiler to ensure that your list only holds Integers. This compile-time checking protects you from those hideous runtime errors.
Compatibility: You can't teach an old dog new tricks, but you can refactor it
Raw types stick around for interaction with legacy code. When updating or writing new code, avoid them like avocado on pizza. For legacy code, use -Xlint:unchecked arsenal to detect and fix unsafe operations.
Code Maintainability: Clean code today saves tomorrow
Generics not only enhance the reliability but maintainability (read geometric coffee breaks). They make interfaces more readable and code clearer because types are checked at compile-time.
Beware of unchecked warnings
You might face unchecked warning at runtime and hidden flaws, such as unexpected exceptions, when you resort to raw types. Use @SuppressWarnings("unchecked") sparingly, it's not a magic wand.
Generics: Your chivalrous knight for type safety
Interface Implementation: Multiply your potential
Generics allow you to implement multiple interfaces with different type parameters, something raw types can't play with, providing more versatile reusable code.
Bytecode: All that glitters is not gold
Even though generics add complexity to your source code, they boil to the same bytecode as raw types due to type erasure.
Best Practice: Do it Alice's way
Always prefer parameterized types over raw types. The only exception is class literals and instanceof checks, where their use is safe.
Evolution: Change is the only constant
Stumble upon raw types in the legacy system, review and transition to parameterized types where possible. New types that support generics should be explicitly parameterized for type safety.
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