Editor Does Not Contain A Main Type – What Does It Mean And How To Fix It?

Introduction

If you are a programmer, you might have encountered an error message that says “Editor does not contain a main type.” This error message can be confusing and frustrating, especially if you are not familiar with the concept of a main type. In this blog post, we will explain what this error message means, what causes it, and how to fix it.

What is a Main Type?

In Java programming language, a main type is the class that contains the main method. The main method is the entry point of a Java program. It is the method that gets executed when you run a Java program. Without a main method, you cannot run a Java program.

What Does “Editor Does Not Contain a Main Type” Mean?

When you see the error message “Editor does not contain a main type,” it means that the Java editor cannot find the main type in your Java file. This error message can occur when you try to run a Java file that does not have a main method or when the main method is not in the expected location.

What Causes “Editor Does Not Contain a Main Type” Error?

There are several reasons why you might see the “Editor does not contain a main type” error message. Here are some of the most common causes:

1. Missing Main Method

As we mentioned earlier, the main method is the entry point of a Java program. If your Java file does not have a main method, you cannot run it. Make sure that your Java file has a main method with the following signature: “` public static void main(String[] args) “`

2. Incorrect Main Method Signature

If your main method has a different signature than the one shown above, you will get the “Editor does not contain a main type” error message. Make sure that your main method has the correct signature.

3. Main Method Not in the Expected Location

By default, the Java editor expects the main method to be in the class with the same name as the Java file. If your main method is not in the expected location, you will get the “Editor does not contain a main type” error message. Make sure that your main method is in the correct class and location.

4. Incorrect File Name

The Java editor expects the file name to match the class name. If your file name does not match the class name, you will get the “Editor does not contain a main type” error message. Make sure that your file name matches the class name.

How to Fix “Editor Does Not Contain a Main Type” Error?

Now that you know what causes the “Editor does not contain a main type” error message, let’s see how to fix it.

1. Add Main Method

If your Java file does not have a main method, you need to add one. Here’s an example of a main method: “` public class MyProgram { public static void main(String[] args) { } } “`

2. Correct Main Method Signature

If your main method has a different signature than the one shown above, you need to correct it. Make sure that your main method has the correct signature.

3. Move Main Method to the Expected Location

If your main method is not in the expected location, you need to move it to the correct class and location.

4. Rename File

If your file name does not match the class name, you need to rename the file to match the class name.

Conclusion

In this blog post, we explained what the “Editor does not contain a main type” error message means, what causes it, and how to fix it. Remember that the main method is the entry point of a Java program, and without it, you cannot run a Java program. Make sure that your Java file has a main method with the correct signature and is in the expected location.