Java class documentation question. <E> <T> <K,V>

[PatFan15]

I am new to Java and I am reviewing the online class documentation from
Sun. I have come across something that I cannot decipher.

I am sure I probably overlooked something and will feel stupid for
asking this once I hear the answer, but I can't seem to find an
explanation.

In the documentation for the java.lang package, there are the following
classes/interfaces listed.
Comparable<T>
Iterable<T>
ThreadLocal<T>

java.util has these among others
Collection<E>
Comparator<T>


What do the <T> and the <E> and the <K,V> mean?

They look like parameters, but I do not recognize the format. If this
is part of a standard documentation format, please feel free to point
me to some documentation on the format and I can read up on it myself.
Thanks.

 

[Robert kebernet Cooper]

Those are part of the new Generics system. They really don't mean
anything except are shortand to let you know of the application of
Generics in the current class. The only ones that are really meaningful
are the <K, V> for key type and value type.
http://www.fawcette.com/javapro/2004_03/online/j2ee_kkreft_03_10_04/

 

[Tony Morris]

I am new to Java and I am reviewing the online class documentation from
Sun. I have come across something that I cannot decipher.

I am sure I probably overlooked something and will feel stupid for
asking this once I hear the answer, but I can't seem to find an
explanation.

In the documentation for the java.lang package, there are the following
classes/interfaces listed.
Comparable<T>
Iterable<T>
ThreadLocal<T>

java.util has these among others
Collection<E>
Comparator<T>


What do the <T> and the <E> and the <K,V> mean?

They look like parameters, but I do not recognize the format. If this
is part of a standard documentation format, please feel free to point
me to some documentation on the format and I can read up on it myself.
Thanks.

They are 'parameterized types'.
http://java.sun.com/j2se/1.5/pdf/generics-tutorial.pdf