Finding patterns and design APIs using Java generics

Question

I use generics quite widely for working with Java and Guava collections. I understand this well when using the API:

• PECS Rule
• {co, contra, in} variance
• Wildcard
• Limited generics

However, it is difficult for me to find generic APIs. Are there design patterns for Java generics? Any links to Java generics can also help. I read:

• Effective Java
• Book "Java Generics and Collections"
• http://www.angelikalanger.com/GenericsFAQ/JavaGenericsFAQ.html

I am familiar with only two patterns in which generics are useful:

• Containment concept: collections of Java, Guava Optional<T>, etc.
• Type parameterization: Guava Predicate<T>,Function<T>

Answer 1

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