Java – Return generic type in a WebService

genericsjavaweb services

I'm green hand in web-service. I wrote a generic class as a value holder like this:

public class SearchResult<T> {
    private List<T> resultSet;
}

Then I write a web-service method:

public SearchResult<Book> getSearchResult(){
    ...
}

When I was using maven-jaxws-plugin to generate client files, I found that the generic type information was gone. They looked like :

public class SearchResult {
   private List<Object> resultSet;
}

public SearchResult getSearchResult(){
    ...
}

My question here is, do the jaxws can keep such kind of generic type information? I tried List as return type, it does work.
Thanks in advance for your help.

Best Answer

If the client code is generated using anything but the source, it will likely not contain the generic information. Once code using generics is compiled, information about generics is lost due to type erasure.

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Java – Create instance of generic type in Java

You are correct. You can't do new E(). But you can change it to

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It's a pain. But it works. Wrapping it in the factory pattern makes it a little more tolerable.

C# – Create Generic method constraining T to an Enum

Since Enum Type implements IConvertible interface, a better implementation should be something like this:

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{
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This will still permit passing of value types implementing IConvertible. The chances are rare though.

Best Answer

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