character encoding - IntelliJ JavaDoc - error - cannot read Input length = 1

Question

I know there are plenty of questions about this problem, but no one of the solved it for me! I'm using the Community Edition of IntelliJ and I tried to run JavaDoc through the IDE. Everytime and it doesn't matter fo which file, I run JavaDoc I got the following output:

javadoc: error - cannot read Input length = 1

I already figured out, that it might be an encoding problem... I'm working on a Windows 10 maschine. I already tried the following:

• JavaDoc argfile encoding error
• Start the terminal from IntelliJ with cmd.exe /K chcp 65001 instead of the default one cmd.exe to set the charset to UTF-8
• I also set the project's default charset through the IntelliJ settings to UTF-8 (See: This Guide)

The problem seems to be the javadoc_args file respectively the path to that file... The path is C:UsersSomebody MüllerAppDataLocalTempjavadoc_args. Also if I view the file from IntelliJ, all ü characters are replaced by an unknown symbol.

I know that I could generate the documentation through a maven plugin, but I would prefer to do it via the IntelliJ IDE...

Could somebody identify the problem in detail and/or provide a solution or maybe parts of it?

EDIT

skomisa described the situation/behaviour in easy words:

For me the javadoc_args file does not exist! I see it is named in the Javadoc window as an argument to javadoc.exe, and if I click the link its content is shown in a pop up window within Intellij IDEA, but if I check in File Explorer there is no such file. Is this the case for you as well? I have no idea how it gets generated. Also, I created a project in a folder named Müller and the ü was rendered as ? within the popup window that showed the content of javadoc_args.

UPDATE 04/12/2018

As skomisa already commented, JetBrains plans to fix this bug in a future version, likely in version 2019.1 (Build 191.2458).

UPDATE 22/02/2019

I know this question is quite old but it seems to be still relevant. I didn't check up to now if JetBrains fixed the bug but a similar one occurred for me when I try to open an JavaFX fxml externally inside of the SceneBuilder. In another post about renaming a Windows 10 user directory I found a possible workaround at least for Windows users! Just create an additional user directory without ü in the path and link to the existing one:

C:
CDUsers
MKLINK /J Müller Mueller

If you now uses the link as directory for project paths it should work fine.

Answer 1

I am unable to generate the Javadoc for a project in Intellij IDEA if the name of the path contains the character ü (u with umlaut). The workaround is to rename the project so that the project directory file path does not contain an umlaut.

To reproduce:

• Use the project wizard to create a trivial Java Hello World project where the root directory name contains ü. I used Müller for testing purposes.

• Ensure that the class for main() contains valid Javadoc documentation.

• Build and run the project to verify that there are no unexpected issues.

• Select Tools > Generate Javadoc, specify an empty Output Directory and click OK.

• Javadoc creation fails with the error - cannot read Input length = 1 (shown below), and clicking the link to C:UsersjohndoeAppDataLocalTempjavadoc_args shows that the ü in the file path is (mis)represented as ?, which presumably is the cause of the Javadoc error.

• However, once the root directory is renamed from Müller to Muller (to remove the umlaut) the Javadoc creation works:

  

• As a sanity check, rename the project from Muller back to Müller to reintroduce the error:

  

Notes:

• As noted in the comments, the javadoc_args file does not exist, and I see no way to prevent its use during the Javadoc creation process.
• Having the project name as Müller is not an issue; it's having ü within the project's file path that causes the problem.
• Environment: Windows 10 + Intellij IDEA 2018 3.1 EAP (Ultimate Edition) + Open JDK 10.
• I raised a bug report with JetBrains for this: https://youtrack.jetbrains.com/issue/IDEA-202849

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Update 11/25/18

There is a workaround for this issue without needing to rename the project's path:

• Run Generate Javadoc and let it fail.
• Click the link to the file .../javadoc_args shown in the Javadoc window.
• Copy and paste the content of the file javadoc_args into a text editor.
• Correct any characters that are misrepresented (e.g. change M?ller to Müller).
• Save the file using UTF-8 encoding, and the same absolute filename.
• Open a Command Prompt window.
• Copy the entire javadoc.exe command from the Javadoc window in Intellij IDEA and paste it to the Command Prompt window.
• Submit the line that was pasted. It will now work because the project's path is correctly specified in the file javadoc_args.