Why generic in java

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I appreciate what you're saying, but that's all just compile-time sugar. The real power of generics in other languages is their use at run-time. Generic Types are checked in compile time only but it can be helpful to avoid bugs.

Maybe I'm lucky but I've never worked with developers that incompetent. Sure another check is nice but If someone is making mistakes like that, I don't want them working on my codebase — Basic. Basic maybe my example is a little too drastic, in complicated and large code bases type checking is helpfull - this is just another tool to help developers in finding bugs.

This is like a debate whether to use asserts in java or always throw Exceptions. I can attest from my experience with dynamic languages Clojure mostly that it is a great pain to track down what a collection holds, especially when your code regularly works with similar representations of the same concept like DB IDs, full entity objects, simplified special-purpose hashes, and so on.

All such collections would typically use the same name. Paul Boddington Paul Boddington Nice suggestion but doesn't this fail if the class I'm deserializing has properties which are generic?

Eg I can't determine, even from your clazz what that generic parameter is? Upvoting for the workaround — Basic. Yes it does fail in that case. Saurabh Saurabh 6, 3 3 gold badges 40 40 silver badges 42 42 bronze badges.

That would be the So Is the only real use for generics to do things like I mentioned in my original post? Ya it avoids ClassCastException and are type safe — Saurabh. My question was more about using the type information at run time - eg to serialise an object using its type information to enumerate parameters. Constraints Java Generics does not support sub-typing. You cannot create generic arrays in Java Generics. Types of Java Generics Generic method : Generic Java method takes a parameter and returns some value after performing a task.

It is exactly like a normal function, however, a generic method has type parameters which are cited by actual type. This allows the generic method to be used in a more general way. The compiler takes care of the type of safety which enables programmers to code easily since they do not have to perform long, individual type castings.

Generic classes : A generic class is implemented exactly like a non-generic class. The only difference is that it contains a type parameter section. There can be more than one type of parameter, separated by a comma. Examples 1. Get hold of all the important Java Foundation and Collections concepts with the Fundamentals of Java and Java Collections Course at a student-friendly price and become industry ready.

The Object is the superclass of all other classes and Object reference can refer to any type object. These features lack type safety. Generics add that type safety feature. We will discuss that type of safety feature in later examples.

There are some fundamental differences between the two approaches to generic types. To create objects of a generic class, we use the following syntax. We can also pass multiple Type parameters in Generic classes. We cannot use primitive data types like int , char. But primitive type array can be passed to the type parameter because arrays are reference type. Generics add type safety through this and prevent errors.

Advantages of Generics: Programs that use Generics has got many benefits over non-generic code. Suppose you want to create an ArrayList that store name of students and if by mistake programmer adds an integer object instead of a string, the compiler allows it.