Eclipse compiler error on simple Java class - java

I am facing a problem while i am trying to compile a code at eclipse in java. The code is the following:
public class New {
public static void main(String[] args){
System.out.println("hello world");
}
}
Parts that have errors are New, String and System. I have checked at error list and the description for error's is like:
Unable to create editor ID
The file does not exist
Any idea why this is happening?


Your project has or classes maybe has beeing dissapeared.
I can give you a possible solution
Solution: Shut down Eclipse IDE Start Eclipse IDE (with -clean to be super-safe) Reimport all projects (UPDATE: Just use File->Import->Existing Project into Workspace and browse your workspace/project directory)

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I'm trying to execute carel programs based on CSA106a Stanford class videos available on YouTube.
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While clicking "run", I get the error:
Error: Could not find or load main class (default package).CheckerboardKarel
Note: other programs that I have created in Neon from scratch are working fine (not imported ones). Please help.
I've attached the screenshots as well.

I can't tell for sure, but I think there might not be a "main" function in what you downloaded. In order for a java program to run the class you are running needs to have a main function. it should look like:
public static void main(String[] args){
...
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I have an open source project (WAR file) imported to my Eclipse.
I have all java code sources in WEB-INF/src/... folder.
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I tried to check the build class and it only has the create method. Tried to clean and build the project, still doesn't resolve my problem. What is the cause of this error? Eclipse seems doesn't build my project.

This is quite strange since I did this before and didn't work, but now it works.
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i'm trying to compile a Java Web Service client with the windows console but there are 100 errors. The client has been made in eclipse, and in it's console it works good. Here it is the code:
public static void main (String[] args)throws Exception{
try{
MireiaUPMPortTypeProxy proxy = new MireiaUPMPortTypeProxy();
proxy.setEndpoint("http://138.4.47.33:8087/axis2/services/MireiaUPM.MireiaUPMHttpSoap11Endpoint/");
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e3.printStackTrace();
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}
When i compile the kind of errors that appear are: Cannot find symbol and org.apache axis.constants does not exist
Could you help me? i'm new at using web services and i'm so lost. The extrange thing for me is that it runs well in the eclipse console, but it doesn't compile.

it runs in Eclipse simply because dependent libs (jars!) are set in eclipse build path.
to be able to compile from OS console/terminal, you have to set classpath correctly. check eclipse build path (right click on project and look for this menu) and add those dependencies in your console command.

Please make sure your all related jar files are on class path when compiling your class files.

Java: Eclipse: Cannot Find Main Class

I had a project that was compiling and running fine. I had also exported the build.xml file without issue. However, today, I clicked Project --> Clean..., and the project will no longer run. It raises the error:
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Is there any way I can undo this?

The answer is probably no, you cannot "undo" this. You can probably fix it by building your project, making sure that the project/class exists and that it contains a public static void main(String ... args) method.

Perhaps the file that you're trying to run was removed from the src folder.

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I have the following code...
public class first
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public static void main (String[] args)
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WebSpec spec = new WebSpec().safari();
spec.safari().open("http://www.google.com"); //opens google.com in Safari
}
}
written in eclipse.
WebSpec is underlined in red giving an error saying "cannot be resolved to be a type"
I assume this is because some of the libraries are not in the right spot? I have tried many different things.
What do I need to do?

Be sure to include all .jar's included in the webspec download in your library. There are .jar's in the lib folder and also one .jar in java\dist of webspec. Eclipse allows you to import libraries by highlighting your project then Project > Properties > Java Build Path > Libraries (tab).

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