Eclipse Error: Problems opening a editor Reason: [Project Name] does not exist solution

Simple description: When you use F3 to enter a method of a class in Eclipse, you are prompted with the following error:

Problems opening an editor Reason: [project name] does not exist

After Baidu on Google some, see the same stackoverflow on the solution of a problem is as follows:

My English is not too good, do not complete the translation of the sentence (behind the English), only simple in Chinese to say the reason for the problem: My project is from GitHub clone down, may be in the import Eclipse, the project is not a "normal" eclipse project, so some features are not yet available, For example [I want to see the reference to the class or method] This function is still not available, the solution is to turn the project first. And I clone the source code inside have Pom.xml, is can use MAVEN to build a project, so I turn into the MAVEN project.

The first way to convert:

Project right key-->configure-->convert to Maven project #This method doesn't solve my problem, and compilation error
The second way to convert:

CD to Project root directory-->mvn eclipse:eclipse #This method solves my problem

Summary of Problem Solving:

Go directly to the Eclipse project by using Maven's commands.

Although the following content does not directly solve the problem, at least give the direction to solve the problem, refer to part of the content:

If you are out of have checked out project to SVN, project checked out are not generally a eclipse project thats why general functio Nality of Eclipse does not work for the same.

To achieve the same functionality of Eclipse like Eclipse Reader and all other shortcuts,we have to convert the checked OU T project to eclipse project.

Steps to Convert checked out project to eclipse project:

Right Click checked-out Project.
Point to Configure.
Click on Convert to Maven Project. (If checked out project is MAVEN project)

These steps'll convert project to Maven project.

All the eclipse functionality'll work for the same.
So I have resolved the issue by checking out the project via "New Project Wizard". Embarrassed
It wasn ' t a Eclipse project in SVN-so-checked out via "Existing project", none of the project Funct Ionality could work.