Develop Reference

How to solve java file mapped to not java file type text

I wanted to add a java class to a project, but I did a mistake and added it as a text file. Then, I removed it and tried to add it again as a java class, but unfortunately it doesn't work anymore. And I get the following error:
Unable to parse template "Class" Error message: ABC.java mapped to not java file type text
As I searched, I faced some solutions like
this one but I can't find File Type under Editor or anything similar that I can change as suggested in the solution.
Any help would be appreciated.
PS: I am using IntelliJ 2018.3.4.
Thanks in advance,

Go on File->Settings and a dialog will open. In that dialog navigate on the left part to Editor/File Types and then you need to choose from the section Recognized File Types Java Class and remove from bottom section the problematic extension (note you have a small minus button on the right)
https://www.jetbrains.com/help/idea/creating-and-registering-file-types.html

This is a variant of Markov's answer that worked in my scenario.
Try going to File->Settings->Editor->File Types and to the Recognized File Types tab. Click the "Auto-detect file type by content" choice, and delete the name of the file you are trying to create from the "File Name Patterns" section by using the minus button.

Select required file type in top list (Recognized File Types) -- do it for "Text files"
In bottom list (Registered Patterns) select undesired pattern -- "SomeFileName.java"
Click on "-" (Minus) button to remove pattern from the list
Repeat 1-2-3 for other undesired patterns
If desired, you can also do this manually by editing config file while IDE is closed. Because it's IDE-wide setting, it is not stored in .idea folder (which has project settinsg only) -- the file to look for is called filetypes.xml and shoudl be located in ~/Library/Preferences/IntelliJIdeaXX/options ( see http://devnet.jetbrains.net/docs/DOC-181 for other OS etc )

Certainly inelegant, but you can simply copy the contents of the file to the clipboard (ctrl-c or similar), delete the file (maybe make a temporary backup somewhere outside the project), then in IntelliJ go to the desired package, right click, select new, select Java Class, name it correctly, and then you can paste in the contents of your file (ctrl-v or similar).

Can I set up a keybind/hot key/macro to paste a line into Eclipse?

I know Eclipse has default keybindings (copy, paste, etc), and you can set keybinds for commands they've already decided on (Generate Setter/Getter, etc) but is it possible to set up a custom command?
For example, I can press Shift+F5 and it'll automatically type or paste "System.out.println();" for me.

In Eclipse Preferences, go to Java->Editor->Templates
Click on "new" to create a new template.
In your template, write in the "pattern" textarea the command you want to be pasted.
For example :
throw new IllegalArgumentException("");
And in the "name" textbox, write the word that matches to that command.
Then, in Eclipse, in your Java Editor, write that word + auto-completion. Eclipse will propose you,among others may be, your template.
The sysout command name is that template :
System.out.println(${word_selection}${});${cursor}

how to do "Find All" for a keyword in opened document in Eclipse?

Hi I want to do search for a keyword like $this->data in an opened php file in eclipse for all its occurrences just like what we do Find All in Dreamweaver or ctrl+f in netbeans,I have tried Ctrl+H and Ctrl+F but it didn't worked for me,anyone can tell me how to do it???Thanks in advance.

In the Search menu, click on File, enter the string you want to seach, make sure to have * in File name patterns (if you want to search in your whole project), then click the search button.

In Eclipse use combination of : ALT + SHIFT + R

Opening a class by typing its name in IntelliJ?

I'm working on a large project with a lot of packages and classes. Its a pain to have to find the right package and then the right file to open. Is there a way to just type in the name of the class that I want to open, and have intellij offer autocomplete suggestions while I type, and then open that file?

Control-N and start typing the class name works for me.
Control-Shift-N does the same trick, but for file names.
Selecting in the source window will open the class in the left explorer pane. Much easier.

Yes, you can use Ctrl+N - of course this answer is too short to post by itself.

cmd + N for java classes.
cmd + shift + N for files.
Double tap on shift for both if you have intellij 13

In eclipse, how can I find where in my classpath a type is coming from?

Maybe I'm misunderstanding something, but..
I want to be able to see that eclipse is getting Foo.class from a .jar (somewhere in the classpath) when it builds project B.
If I use the 'open type' (Ctrl + Shift + T) it seems that that just shows me all the places that Foo.class exists in my WORKSPACE?
Many thanks..
EDIT: I'm trying to find which jar is introducing a class into my code. It's not my jar. I don't have the source. I can't therefore open it and click it. I want a window that I can type in a type name, like 'Foo.class', and it tells me where that class is being brought in in my classpath. That must be quite simple? Ideally it would also tell me which occurrences later in the classpath were being hidden because it found the first one first. Does that make sense or am I talking nonsense?
EDIT: Guess I'm not making it clear. I don't have a piece of code that uses Foo. It's that somewhere in some included open source library something calls something calls Foo. So I can't highlight or right click anything. I guess I could write a piece of code that has it in? Seems a bit clunky..

Came here looking for the same, so though the question is two years old:
In eclipse Mars, if you press shift+control+T / ⇧+⌘+T on mac to bring up the "Open Type" dialog, the package as well as the name and path of the jar file is shown in the bottom of the window for a selected class.

Alternate Solution : particularly if you want to know the jar files which have needed class , you can search using WINRAR.
Use Find in WinRAR
i) Open WinRAR
ii) Open lib folder ( which contains all jar files ) in WinRAR
iii) Click on Find , type any classname (ex : ClassWriter.class )
iv) Click on OK
you will see all the classes which are named as ClassWriter.class in all jar files in lib folder.

Since there seems to be no good solution or plugin for this, I often create a dummy class in the root of my project:
public class Find {
public static void main(String[] args) {
System.out.println(
SomeClass.class.getProtectionDomain().getCodeSource().getLocation());
}
}
Then I just delete the class. A plugin would be nice :)

Look for .classpath file in your project.
OR
Where ever class Foo is used, go to that statement, while Ctrl key is pressed, left click the class name. Eclipse will take you to the location of Foo class. This will the Foo class eclipse is referring while building your code.

Right click on the class name, then select "Open declaration" (or just press F3), if you don't have a source attached, you can do it at that point. In the package explorer you have the functionality "Link with Editor" (a button with a couple of arrows going back and forward), that redirects you to the jar of the class. If you don't have the source, you still can use the "Link with Editor" functionality to see the propietary jar