jar should throw exception when working with invalid Jar files

Name: rjC112767 Date: 08/10/2000


jar should throw error/exception when working with otherfile
types,corrupted file

case 1:When trying to extract or list the content of a jar file,(in
which data are corrupted i.e.,No data found)
it comes to prompt without any error message.

case 2:when trying to extract a file not of jar type it is coming to
prompt without any error message.

case 3:when creating jar file it is not checking that the file name is
with .jar extension and if we give with any other extension it is
created and extracted properly.


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