Samples java WAR fails to build image using graalvm java8(non-native)

[nicolaasg]

I am using the code from
https://github.com/paketo-buildpacks/samples/tree/main/java/war

Modified pom.xml to set java.version to 8
Ran mvn package to create war file.

Trying to build an image using the following command produces an error:

pack build --verbose --path target/demo-0.0.1-SNAPSHOT.war application/war --env BP_JVM_VERSION=8 --builder paketobuildpacks/builder:base --buildpack gcr.io/paketo-buildpacks/graalvm --buildpack gcr.io/paketo-buildpacks/apache-tomcat

---

===> BUILDING
Starting build
Running build for buildpack paketo-buildpacks/[email protected]
Looking up buildpack
Finding plan
Running build for buildpack Paketo GraalVM Buildpack 6.2.2
Creating plan directory
Preparing paths
Running build command
Paketo GraalVM Buildpack 6.2.2
https://github.com/paketo-buildpacks/graalvm
Build Configuration:
$BP_JVM_VERSION 8 the Java version
Launch Configuration:
$BPL_JVM_HEAD_ROOM 0 the headroom in memory calculation
$BPL_JVM_LOADED_CLASS_COUNT 35% of classes the number of loaded classes in memory calculation
$BPL_JVM_THREAD_COUNT 250 the number of threads in memory calculation
$JAVA_TOOL_OPTIONS the JVM launch flags
No valid JRE available, providing matching JDK instead. Using a JDK at runtime has security implications.
GraalVM JDK 8.0.292: Contributing to layer
Downloading from https://github.com/graalvm/graalvm-ce-builds/releases/download/vm-21.1.0/graalvm-ce-java8-linux-amd64-21.1.0.tar.gz
Verifying checksum
Expanding to /layers/paketo-buildpacks_graalvm/jdk
Adding 129 container CA certificates to JVM truststore
unable to invoke layer creator
unable to count JVM classes
unable to walk /layers/paketo-buildpacks_graalvm/jdk
unable to open ZIP /layers/paketo-buildpacks_graalvm/jdk/jre/languages/nfi/builder/svm-none.jar
zip: not a valid zip file
ERROR: failed to build: exit status 1
ERROR: failed to build: executing lifecycle: failed with status code: 145

---

pack --version
v0.19.0+git-6b588dc

[dmikusa]

Sorry for the delayed response. It looks like there is a JAR file that's bundled with GraalVM JDK that isn't valid, at least according to the Go libraries we use.

This is happening when we go through and try to count up all of the class files to estimate metaspace needs. I suspect that we should probably just not fail on this error and just log a warning. It might even be reasonable to have a max errors counter, like 5 or 10, where if you go over that threshold then it errors.

https://github.com/paketo-buildpacks/libjvm/blob/main/count/count_classes.go#L59-L63

Since this is a libjvm issue, I'm going to move this over to that project. Thanks for raising this up!