Can't build LanguageTool anymore

I just updated from xubuntu-16.04 to xubuntu-18.04 and I cannot build LanguageTool anymore.

Is there a known issue?

Here is the error:

$ mvn clean
...
[INFO] BUILD SUCCESS
...

$ mvn package
WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by com.google.inject.internal.cglib.core.$ReflectUtils$1 (file:/usr/share/maven/lib/guice.jar) to method java.lang.ClassLoader.defineClass(java.lang.String,byte[],int,int,java.security.ProtectionDomain)
WARNING: Please consider reporting this to the maintainers of com.google.inject.internal.cglib.core.$ReflectUtils$1
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release
[INFO] Scanning for projects...
[WARNING] The project org.languagetool:languagetool-parent:pom:4.2-SNAPSHOT uses prerequisites which is only intended for maven-plugin projects but not for non maven-plugin projects. For such purposes you should use the maven-enforcer-plugin. See https://maven.apache.org/enforcer/enforcer-rules/requireMavenVersion.html
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Build Order:
[INFO] 
[INFO] languagetool-parent
[INFO] LanguageTool Style and Grammar Checker Core
[INFO] English module for LanguageTool
[INFO] Persian module for LanguageTool
[INFO] French module for LanguageTool
[INFO] German module for LanguageTool
[INFO] Polish module for LanguageTool
[INFO] Catalan module for LanguageTool
[INFO] Italian module for LanguageTool
[INFO] Breton module for LanguageTool
[INFO] Dutch module for LanguageTool
[INFO] Portuguese module for LanguageTool
[INFO] Russian module for LanguageTool
[INFO] Asturian module for LanguageTool
[INFO] Belarusian module for LanguageTool
[INFO] Chinese module for LanguageTool
[INFO] Danish module for LanguageTool
[INFO] Esperanto module for LanguageTool
[INFO] Galician module for LanguageTool
[INFO] Greek module for LanguageTool
[INFO] Icelandic module for LanguageTool
[INFO] Japanese module for LanguageTool
[INFO] Khmer module for LanguageTool
[INFO] Lithuanian module for LanguageTool
[INFO] Malayalam module for LanguageTool
[INFO] Romanian module for LanguageTool
[INFO] Slovak module for LanguageTool
[INFO] Slovenian module for LanguageTool
[INFO] Serbian module for LanguageTool
[INFO] Spanish module for LanguageTool
[INFO] Swedish module for LanguageTool
[INFO] Tamil module for LanguageTool
[INFO] Tagalog module for LanguageTool
[INFO] Ukrainian module for LanguageTool
[INFO] Simple German module for LanguageTool
[INFO] All language modules for LanguageTool
[INFO] LanguageTool common GUI classes
[INFO] LanguageTool command-line version
[INFO] LanguageTool embedded HTTP server
[INFO] LanguageTool tools for building dictionaries
[INFO] LanguageTool stand-alone GUI
[INFO] LanguageTool LibreOffice/OpenOffice extension
[INFO] Hunspell native libs for LanguageTool
[INFO] LanguageTool Wikipedia tools
[INFO] LanguageTool HTTP API client
[INFO] LanguageTool development tools
[INFO] LanguageTool RPM
[INFO] 
[INFO] ------------------------------------------------------------------------
[INFO] Building languagetool-parent 4.2-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- maven-enforcer-plugin:1.0:enforce (enforce-maven) @ languagetool-parent ---
[INFO] 
[INFO] ------------------------------------------------------------------------
[INFO] Building LanguageTool Style and Grammar Checker Core 4.2-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- maven-enforcer-plugin:1.4.1:enforce (enforce-maven) @ languagetool-core ---
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ languagetool-core ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 17 resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.7.0:compile (default-compile) @ languagetool-core ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 200 source files to /home/pel/sb/languagetool/languagetool-core/target/classes
[INFO] /home/pel/sb/languagetool/languagetool-core/src/main/java/org/languagetool/JLanguageTool.java: Some input files use or override a deprecated API.
[INFO] /home/pel/sb/languagetool/languagetool-core/src/main/java/org/languagetool/JLanguageTool.java: Recompile with -Xlint:deprecation for details.
[INFO] 
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ languagetool-core ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 37 resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.7.0:testCompile (default-testCompile) @ languagetool-core ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 89 source files to /home/pel/sb/languagetool/languagetool-core/target/test-classes
[INFO] /home/pel/sb/languagetool/languagetool-core/src/test/java/org/languagetool/tools/RuleMatchAsXmlSerializerTest.java: Some input files use or override a deprecated API.
[INFO] /home/pel/sb/languagetool/languagetool-core/src/test/java/org/languagetool/tools/RuleMatchAsXmlSerializerTest.java: Recompile with -Xlint:deprecation for details.
[INFO] 
[INFO] --- maven-surefire-plugin:2.20.1:test (default-test) @ languagetool-core ---
[INFO] ------------------------------------------------------------------------
[INFO] Reactor Summary:
[INFO] 
[INFO] languagetool-parent ................................ SUCCESS [  0.151 s]
[INFO] LanguageTool Style and Grammar Checker Core ........ FAILURE [  3.940 s]
[INFO] English module for LanguageTool .................... SKIPPED
[INFO] Persian module for LanguageTool .................... SKIPPED
[INFO] French module for LanguageTool ..................... SKIPPED
[INFO] German module for LanguageTool ..................... SKIPPED
[INFO] Polish module for LanguageTool ..................... SKIPPED
[INFO] Catalan module for LanguageTool .................... SKIPPED
[INFO] Italian module for LanguageTool .................... SKIPPED
[INFO] Breton module for LanguageTool ..................... SKIPPED
[INFO] Dutch module for LanguageTool ...................... SKIPPED
[INFO] Portuguese module for LanguageTool ................. SKIPPED
[INFO] Russian module for LanguageTool .................... SKIPPED
[INFO] Asturian module for LanguageTool ................... SKIPPED
[INFO] Belarusian module for LanguageTool ................. SKIPPED
[INFO] Chinese module for LanguageTool .................... SKIPPED
[INFO] Danish module for LanguageTool ..................... SKIPPED
[INFO] Esperanto module for LanguageTool .................. SKIPPED
[INFO] Galician module for LanguageTool ................... SKIPPED
[INFO] Greek module for LanguageTool ...................... SKIPPED
[INFO] Icelandic module for LanguageTool .................. SKIPPED
[INFO] Japanese module for LanguageTool ................... SKIPPED
[INFO] Khmer module for LanguageTool ...................... SKIPPED
[INFO] Lithuanian module for LanguageTool ................. SKIPPED
[INFO] Malayalam module for LanguageTool .................. SKIPPED
[INFO] Romanian module for LanguageTool ................... SKIPPED
[INFO] Slovak module for LanguageTool ..................... SKIPPED
[INFO] Slovenian module for LanguageTool .................. SKIPPED
[INFO] Serbian module for LanguageTool .................... SKIPPED
[INFO] Spanish module for LanguageTool .................... SKIPPED
[INFO] Swedish module for LanguageTool .................... SKIPPED
[INFO] Tamil module for LanguageTool ...................... SKIPPED
[INFO] Tagalog module for LanguageTool .................... SKIPPED
[INFO] Ukrainian module for LanguageTool .................. SKIPPED
[INFO] Simple German module for LanguageTool .............. SKIPPED
[INFO] All language modules for LanguageTool .............. SKIPPED
[INFO] LanguageTool common GUI classes .................... SKIPPED
[INFO] LanguageTool command-line version .................. SKIPPED
[INFO] LanguageTool embedded HTTP server .................. SKIPPED
[INFO] LanguageTool tools for building dictionaries ....... SKIPPED
[INFO] LanguageTool stand-alone GUI ....................... SKIPPED
[INFO] LanguageTool LibreOffice/OpenOffice extension ...... SKIPPED
[INFO] Hunspell native libs for LanguageTool .............. SKIPPED
[INFO] LanguageTool Wikipedia tools ....................... SKIPPED
[INFO] LanguageTool HTTP API client ....................... SKIPPED
[INFO] LanguageTool development tools ..................... SKIPPED
[INFO] LanguageTool RPM ................................... SKIPPED
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 4.422 s
[INFO] Finished at: 2018-05-13T11:34:28+02:00
[INFO] Final Memory: 28M/104M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-surefire-plugin:2.20.1:test (default-test) on project languagetool-core: Execution default-test of goal org.apache.maven.plugins:maven-surefire-plugin:2.20.1:test failed.: NullPointerException -> [Help 1]
[ERROR] 
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR] 
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/PluginExecutionException
[ERROR] 
[ERROR] After correcting the problems, you can resume the build with the command
[ERROR]   mvn <goals> -rf :languagetool-core

I’m using git SHA1 addc42f7ed4e265298fa3fa69340d8595b089c75 (May 13).

Which version of Java is that? I’m still using Java 8.

$ java -version
openjdk version "10.0.1" 2018-04-17
OpenJDK Runtime Environment (build 10.0.1+10-Ubuntu-3ubuntu1)
OpenJDK 64-Bit Server VM (build 10.0.1+10-Ubuntu-3ubuntu1, mixed mode)

I can try another version later when I find time.

I just did a cursory scan on google and it seems that Java-10 is not Java-8 compatible.

Just to confirm that I can successfully build LanguageTool when using Java8 instead of Java 10. So it is not a blocking issue for me. However, it would be nice if LanguageTool built successfully with Java 10.