Error for deploying to heroku: illegal character: '\ufeff' - heroku

Question

All.
I am testing whether it would be useful to develop a web application in Heroku. So, I'm trying to follow the guide that is "Deploying Spring Boot Applications to Heroku".(link: https://devcenter.heroku.com/articles/deploying-spring-boot-apps-to-heroku)
I can follow the guide to check the page returning hello world, but I'm having a problem connecting postgresql. When I try to deploy DatabaseConfig.java file to git, it fails with the following log in vscode. How can I solve it?
$ git push heroku master
Enumerating objects: 24, done.
Counting objects: 100% (24/24), done.
Delta compression using up to 12 threads
Compressing objects: 100% (12/12), done.
Writing objects: 100% (15/15), 1.36 KiB | 463.00 KiB/s, done.
Total 15 (delta 3), reused 0 (delta 0)
remote: Compressing source files... done.
remote: Building source:
remote:
remote: -----> Java app detected
remote: -----> Installing JDK 1.8... done
remote: -----> Executing Maven
remote: $ ./mvnw -DskipTests clean dependency:list install
remote: [INFO] Scanning for projects...
remote: [INFO]
remote: [INFO] -------------------------< com.daview:daview >--------------------------
remote: [INFO] Building demo 0.0.1-SNAPSHOT
remote: [INFO] --------------------------------[ jar ]---------------------------------
remote: [INFO]
remote: [INFO] --- maven-clean-plugin:3.1.0:clean (default-clean) # daview ---
remote: [INFO]
remote: [INFO] --- maven-dependency-plugin:3.1.2:list (default-cli) # daview ---
remote: [INFO]
remote: [INFO] --- maven-resources-plugin:3.1.0:resources (default-resources) # daview ---
remote: [INFO] Using 'UTF-8' encoding to copy filtered resources.
remote: [INFO] Copying 1 resource
remote: [INFO] Copying 0 resource
remote: [INFO]
remote: [INFO] --- maven-compiler-plugin:3.8.1:compile (default-compile) # daview ---
remote: [INFO] Changes detected - recompiling the module!
remote: [INFO] Compiling 2 source files to /tmp/build_d5a7a4a08b5f6a2624f3313e54f0a54a/target/classes
remote: [INFO] -------------------------------------------------------------
remote: [ERROR] COMPILATION ERROR :
remote: [INFO] -------------------------------------------------------------
remote: [ERROR] /tmp/build_d5a7a4a08b5f6a2624f3313e54f0a54a/src/main/java/com/daview/daview/DatabaseConfig.java:[1,1] illegal character: '\ufeff'
remote: [ERROR] /tmp/build_d5a7a4a08b5f6a2624f3313e54f0a54a/src/main/java/com/daview/daview/DatabaseConfig.java:[1,10] class, interface, or enum expected
remote: [INFO] 2 errors
remote: [INFO] -------------------------------------------------------------
remote: [INFO] ------------------------------------------------------------------------
remote: [INFO] BUILD FAILURE
remote: [INFO] ------------------------------------------------------------------------
remote: [INFO] Total time: 4.196 s
remote: [INFO] Finished at: 2020-05-05T17:33:46Z
remote: [INFO] ------------------------------------------------------------------------
remote: [ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.8.1:compile (default-compile) on project daview: Compilation failure: Compilation failure:
remote: [ERROR] /tmp/build_d5a7a4a08b5f6a2624f3313e54f0a54a/src/main/java/com/daview/daview/DatabaseConfig.java:[1,1] illegal character: '\ufeff'
remote: [ERROR] /tmp/build_d5a7a4a08b5f6a2624f3313e54f0a54a/src/main/java/com/daview/daview/DatabaseConfig.java:[1,10] class, interface, or enum expected
remote: [ERROR] -> [Help 1]
remote: [ERROR]
remote: [ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
remote: [ERROR] Re-run Maven using the -X switch to enable full debug logging.
remote: [ERROR]
remote: [ERROR] For more information about the errors and possible solutions, please read the following articles:
remote: [ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
remote:
remote: ! ERROR: Failed to build app with Maven
remote: We're sorry this build is failing! If you can't find the issue in application code,
remote: please submit a ticket so we can help: https://help.heroku.com/
remote:
remote: ! Push rejected, failed to compile Java app.
remote:
remote: ! Push failed
remote: Verifying deploy...
remote:
remote: ! Push rejected to daview.
remote:
To https://git.heroku.com/daview.git
! [remote rejected] master -> master (pre-receive hook declined)
error: failed to push some refs to 'https://git.heroku.com/daview.git'

Answer 1

I found the solution!
It is the problem with encoding!
I can find the character which is '\ufeff' by changing the encoding type like EUC-KR not UTF. So I fixed the code correctly and saved back to utf-8.