是否需要从像IntelliJ这样的IDE编译整个程序才能从命令行运行？

Question

Say I setup a program in intelliJ in java and I have multiple classes and everything setup. I am trying to run this program from the command line, but I keep seeing in tutorials they are using the command javac programname.java and they are compiling the program and then running it.

But I have multiple classes and I'm using intelliJ to do everything. Do I just compile it from intellij or what's the best way to do this? Do I even need to compile it, or is it all ready compiled?

I just want to be able to run my main class from the command line.

Answer 1

You do not need to compile it. Just run your main class and IDE will do the rest.

Do remember to add required parameters to you main program, if any.

This link would be helpful https://www.jetbrains.com/idea/help/running-applications.html

Answer 2

You should think of the main method() as the entry point in your program. In other words, main() is the method that starts your program. So, when you are adding other classes intellij just adds imports to your other classes just like when your importing from the api. So, assuming that your imports are correct you need to take the following steps.

1. Compile all of your .java files (including the file with main which is sometimes referred to as a test client) using javac myFile.java

2. Run your compiled, main class with main method() by using java myClass

Edit: you must ensure that you add the location of your .class file to your classpath. So, if its in the current folder then add . to your classpath. Note that the windows classpath separator is a semi-colon ie ;

Then you can use java -cp to compile and run

javac -cp . PackageName/*.java
java -cp . PackageName/ClassName_Having_main

Answer 3

You can make an executable jar :

More information : http://www.mkyong.com/java/how-to-make-an-executable-jar-file/

Intellij : How to build jars from IntelliJ properly?