How does java know what class to invoke the main() method of?

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SUMMARY

In Java, the entry point for execution is determined by the manifest file within a JAR (Java Archive) file. The manifest file specifies the main class to invoke the main() method. Unlike C++ and C#, where the main function can vary based on the compiler or context, Java relies on the 'Main-Class' attribute in the manifest to identify which class to execute. This ensures that when a JAR is run, the correct main() method is invoked as intended.

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Whovian
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In C++, pretty much any global main() function gets run. In C#, amy class's Main() method gets run, and having multiple Main() methods in multiple classes should give a compilation error(?). But if we have a .jar, when running it, how do we know which class's main() method the .jar will run?
 
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Hey Whovian.

Actually for C and C++, you have to provide an entrypoint in many cases for different compilers and the 'main' is not always assumed to be main (although it is set by default to do this).

As for your question in Java, a quick google search gave this:

http://docs.oracle.com/javase/tutorial/deployment/jar/appman.html
 

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