HashMapTest.java uses unchecked or unsafe operations.

[Eranga]

HashMap<String,Object> h

this feature was not in 1.4 :cool:
in 1.4 we have to write:

HashMap h

Yep, that's true. But still you get the warning buddy.

[rjuyal]

here is why it will do so,
Type Erasure (The Java™ Tutorials > Learning the Java Language > Generics)

but even now, i don't know what is the logic :(

[sukatoa]

I am compiling and running my code using same java version. if i use
HashMap h
then there following error:
Note: HashMapTest.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.

Try to compile it on terminal/cmd.

Try to post the warnings here.