generics - Code explanation in Java -

this morning came across code, , have absolutely no idea means. can explain me these <t> represent? example:

public class myclass<t> ...  bits of code   private something<t> so;  private otherthing<t> to;  private class<t> c; 

thank you

you have bumped "generics". explained nicely in guide.

in short, allow specify type storage-class, such list or set contains. if write set<string>, have stated set must contain strings, , compilation error if try put else in there:

set<string> stringset = new hashset<string>(); stringset.add("hello"); //ok. stringset.add(3);       ^^^^^^^^^^^ //does not compile 

furthermore, useful example of generics can allow more closely specify abstract class:

public abstract class abstclass<t extends variable> { 

in way, extending classes not have extend variable, need extend class extends variable.

accordingly, method handles abstclass can defined this:

public void dothing(abstclass<?> abstextension) { 

where ? wildcard means "all classes extend abstclass variable".