如何在Eclipse中指定嵌套的泛型

Question

I want to specify this type:

Map<String,Map<String,String>> blah = null;

But Eclipse refuses this. I am not sure if it is Eclipse or the Java parser.

I had similar issues when trying to write my own java parser at study times: ">>" was regarded as the shift operator.

What's going on here?

Edit: java works for this.

Answer 1

It could be because your eclipse is set up to use a compiler version for java 1.4 which doesn't have generics.

Does it work if you just do

Map<String,String> map = null;

EDIT: Setting in eclipse

Answer 2

No problem for me as expexted...

Indeed you can for sure define nested generic like you was doing

Map<String,Map<String,String>> blah = null;

Event doing this will not cause problems

Map<String,Map<String,Map<String,String>>> blah = null;

It is not a problem of nested generic (Java support this feature), it is a problem of generic support. Be sure to have the right settings for your compiler in Eclipse, you have to set at least java 1.5 for enabling generics. (Windows->Preferences->Java-Compiler and then check the version).