在Eclipse没有选项的情况下如何建一个Java项目

Question

I am trying to build a Java project I found on Github using Eclipse. The project has no maven & gradle files and no.jar files in the repo. I am getting the following error when I try to build the project within Eclipse. "No actions available." Also, When I select the option, Right-click the project and choose Configure > Configure and Detect Nested Projects, this is not working. Please see the images attached. This is the current repo I am trying to run, https://github.com/copley/def-guide-to-java-swing.git

Answer 1

The notion of "build" and "run" are different. You stated that you get "No actions available" when you build it, but your screenshot clearly shows that you're trying to execute the "Run As" operation.

You said "The project has no maven & gradle files and no.jar files in the repo".

First, do you know what a "maven file" is? Your screenshot shows a "M" in the project icon. That shows that Eclipse recognizes that project as a Maven project. Do you have a "pom.xml" file in the project? That is the file that declaratively specifies to Maven how to build this project.

Second, what do you mean by "no.jar files in the repo"? What repo are you talking about?

In the top screenshot, where you attempted the "Run As", it appears that you selected one of the Java source files, not the project itself. The "Run As" operation can only work if it knows how to run the object that you've selected. If you've selected a Java source file, it will only be runnable if that class has a "main()" method with the proper signature.

The other curious problem is that the github project you cite has no source file named "ColorSample.java", or even a folder named "Ch01". That project uses Maven for all its examples, and a couple of sample classes I looked at all have "main()" method with the proper signature.