Opening a jar file

Question

hey all, i only have one class that i want to make a jar file. i make sure the msdos prompt is focused on the right folder, and i use the following command line...
jar cf writer.jar writer.class
it makes a jar file without any problems, but when i go to open the jar file, nothing happens. whats goin on? also, how would i go about creating a manifest file?

Answer 1

First of all, a useful tip: a JAR file is nothing more or less then a ZIP file, so you can use WinZip to open and edit it.
Second, you have to edit the manifest file in the created jar file. Open it with WinZip and add a line containting "Main-Class: com.test.TestClass", with offcourse your classname instead of "com.test.TestClass".
Then, last but not least, you have to open the JAR file with java.exe or javaw.exe. In windows (shift+)right click and select "open with". If you select the "always open with" checkbox, windows should remember that it has to open jar files with the particular exe. The difference between both is that javaw will not show a console, while java will.
greetz.
if it is not completely clear, let me know.