realm-java | Realm is a mobile database : a replacement for SQLite & ORMs | Database library

I’m currently reading a tutorial page of Spring Boot (https://spring.io/guides/gs/uploading-files/#initial) in order to check how to upload an image file, but I don’t quite understand the “Build an executable JAR” part of “Run the Application” Chapter.

I downloaded the project via the link on the tutorial’s page, and copied and pasted all the files, and I wrote “./gradlew bootRun” on the command prompt, just as written in the Build an executable JAR part of the page, but I’m unable to run the program.

To describe my situation in a more concrete way, I moved to the directory where there is a gradle file (in my PC environment, it’s C:\Users\marra\Documents\workspace-spring-tool-suite-4-4.5.1.RELEASE\ImgUpload\gs-uploading-files\initial ) by cd command, and then wrote “./gradlew bootRun” and hit the Enter button of the keyboard, but still just get an error message “BUILD FAILED”.

Here I come up with 2 questions.

・First of all, am I properly following the tutorial’s instructions in the first place? In other words, what I did is “move to the C:\Users\marra\Documents\workspace-spring-tool-suite-4-4.5.1.RELEASE\ImgUpload\gs-uploading-files\initial directory and wrote “./gradlew bootRun” and hit the Enter”, but was this the right way of running the tutorial’s program? If my way of doing it is wrong, how should I have run the program? What does “you can run the application by using ./gradlew bootRun” mean?

・Another possibility of this failure is that I get an error message even though I do follow the tutorial’s instructions properly. But in that case, which part did I do wrong? When I try to run the program and it fails, the command prompt shows an error message “Execution failed for task ':compileJava'. > Compilation failed; see the compiler error output for details.”. I did some research by myself, and for example on a page like https://github.com/realm/realm-java/issues/5910 suggests that “Any compilation failure gets this message.”. Perhaps I might not have copied and pasted all the sample code of the files properly, but the problem is that I don’t know which folder’s which file’s which line to check. I added “--debug” to the “./gradlew bootRun” command to see what kind of errors I get, and I got the following.

When using app bundles, there is a risk that a user will "sideload" a customised APK onto an incompatible device. This may cause a crash, as the required densities / languages won't be present.

To resolve this, there is a handy MissingSplitsManager inside Google Play Core. This shows the user a helpful error on startup instead of crashing. All that needs to be done is adding the following to the application class: