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I can't run the program in intelliJ

I created a project unchecked (Create project form template)
and added new class named demo.
but when after compiling, I couldn't run the code intellij didin't show me result.
"Edit configuration" only appeared like this:
I don't know what to do :(
I saw someone run the code using Intellij without writing package.
So I don't think that it doesn't work because I didn't write package.
What can I do?

You are missing the String[] args parameter in your main method:
public static void main(String[] args) {
}

Add the args parameter to the main method. Then right click into the editor -> and select "Run demo.main()"

use func from another module java using spring

In my project there are some modules.
I want to use func from another module in my project.
I tried some ways to do this.
When I wrote:
studentManager studentMng = new studentManager();
studentMng.createStudent(student);
in line 1, I can see that studentMng is null (in the debugger).
So I get nullPointerException.
All this code located under main func (public static void main(String[] args)
then if I use another option I get conflict about static.
What I have to do?
Thanks.

Java Eclipse error method not found in class

The error states Error main method not found in class. Please define the main method as:
public static void main(String[] args).
Eclipse was working for me a few days ago, but now it just gives me that message
an example would be
public class Test {
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println("Hello World");
}
}

Check if exists any error in your project. Not just the compilation errors. Click on project and check the "Problems" view in Eclipse. You need to remove all of "Errors".

First clean your project Using Project-->Clean and then build it again.
Also make sure that your build path is properly set.

I ran into the same issue. Just clean your project..save your project and then run it.

Check whether you have created a class with the name "String". If you have created a class with the name "String", the compiler will not be able to resolve the conflict between 2 classes i.e. java.lang.String and your String class therefore it won't recognize the main method.
So just remove that String class or rename it.It happened to me also.. I resolved using this only.

I ran into this problem also when I moved the location of the main method in my program to another file in the same program. If this is what happened to you, the fix is to go to the top of Eclipse near the bug and play icons and change the "Run as..." field to "Java application" from whatever its previous location was.

Try to resturt Eclipse in a new workspace.

Maybe you are creating 2 classes in the same package or u have defined one of your defined class name as "String". If you have then change that classname to something else , because at that time compiler cannot differentiate between java.lang.String and your user defined class "String". So jst chage the name of that String class.

Main method not found even if I've declared it

I want to create a simple java class, with a main method, but when I compile my code, I get this error message :
Error: Main method not found in class errors.TestErrors, please define
the main method as: public static void main(String[] args)
This is the source code :
package errors;
public class TestErrors {
public static void main(String[] args){
System.out.println("hello");
}
}
Why I'm seeing this error, as you can notice I've alreader declared the main method !

As said in my comments, looks like you've declared a String class among your own classes. To prove this, I've created a basic example:
class String {
}
public class CarelessMain {
public static void main(String[] args) {
System.out.println("won't get printed");
}
public static void main(java.lang.String[] args) {
System.out.println("worked");
}
}
If you execute this code, it will print "worked" in the console. If you comment the second main method, the application will throw an error with this message (similar for your environment):
Error: Main method not found in class edu.home.poc.component.CarelessMain, please define the main method as:
public static void main(String[] args)

This usually happens if ur complete project isnotconfigured correctly
or one of your class in project has still some errors
in such cases IDE will prompt stating the same that project contains some error
and you still proceed (ie run your class)
as project has some bugs new classes will not be created and IDE will run
the class which was available previously
to make sure this is ur case u can add new class in your project and try to run it and if ur getting no such class exist then there its is a perfect evidence

Just check your java file, it has not been saved. Please save all java files before compiling.

If the answers above are not working for you: make sure "main" is not capitalized in your method definition.
OK:
public static void main(String[] args)
ERROR:
public static void Main(String[] args)
Though the error message makes the required syntax for the main method clear, incorrect caps can be hard to spot. It took me ~30 minutes of troubleshooting to find this typo today. This was clearly not an issue for the OP, but is another easy/likely way to produce the same error message, and this answer may help other users.

I had this issue just now. This error came up because the JRE file that i switched out didn't had the full library. After I corrected/added the right JRE system library the problem went away.

Right click on the class name (which you are trying to run)->Run As->Run Configurations->Under Main Class Tab
Write your main class name and hit on Run.

Try commenting the first line.
//package errors;

Don't run android application in eclipse

When I want to run my java code, I have this problem :
Exeption in thread "main" java.lang.ArrayIndexOutOfBoundsException:0
at com.ibm.icu.text.BreakDictionary.main(BreakDictionary.java:44)
i can't run my code... It's simple
public class main{
public static void main(String[] args){
System.out.print("Hi");
}
}

WTF is com.ibm.icu.text.BreakDictionary?
Make sure of the class whose main you are running. I suspect you're not running your class. Your java command should look like this:
java -cp somepath com.mycompany.mypackage.MyClass
Better yet, use an IDE like eclipse that make it easy to run a class
Also, rename your class from main to MyClass - anything with a leading capital letter - it's good coding style

Exeption in thread "main" java.lang.ArrayIndexOutOfBoundsException:0
at com.ibm.icu.text.BreakDictionary.main(BreakDictionary.java:44)
This exception says that you are running the main method in a class named BreakDictionary. In your sample code the class is called main.
You can solve this in eclipse by right-clicking your class and select run as and then java application. This will ensure that you are using your main class as the entry point and not BreakDictionary (which seems to either be on your classpath or you are simply not running the correct project in eclipse).