3.49.5/maven: module jdk.compiler does not export com.sun.tools.javac.processing ?

[DrMicrobit]

Hi all,

would it be possible for the checkerframework to include a fully developed toy project for a maven integration?

I am battling an error that, for the life of me, I am unable to find out what the reason is. I am attaching to this issue

910_checkerframework_min.tar.gz

a minimal project for replication: unpack, cd to directory, then mvn install. The error I am encountering is this:

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.13.0:compile (default-compile) on project btool: Fatal error compiling: java.lang.IllegalAccessError: class org.checkerframework.javacutil.AbstractTypeProcessor (in unnamed module @0x23f86d8a) cannot access class com.sun.tools.javac.processing.JavacProcessingEnvironment (in module jdk.compiler) because module jdk.compiler does not export com.sun.tools.javac.processing to unnamed module @0x23f86d8a -> [Help 1]

As far as I can see, the needed export is present in the pom.xml and I looked into the docs and a bit everywhere on the net to find out what I am doing wrong, but I have no clue.

My environment: macOS Sequoia 15.6.1, Java 17 TEM installed via sdkman (sdk install java 17.0.16-tem), maven 3.9.11 installed via homebrew (brew install maven).

Maybe it's something obvious in the pom.xml, therefore I am including it here, too.

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<groupId>com.bjtrain</groupId>
	<artifactId>btool</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>btool</name>
	<description>Small test</description>
	<properties>
		<java.version>17</java.version>
	</properties>


	<dependencies>
		<!-- BaCh -->
		<dependency>
			<groupId>org.checkerframework</groupId>
			<artifactId>checker</artifactId>
			<version>3.50.0</version>
		</dependency>
		<dependency>
			<groupId>org.checkerframework</groupId>
			<artifactId>checker-qual</artifactId>
			<version>3.50.0</version>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<!-- BaCh -->
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-compiler-plugin</artifactId>
				<configuration>
					<release>17</release>
					<!-- Needed for checkerframework -->
					<compilerArgs combine.children="append">
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.api=ALL-UNNAMED</arg>
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.code=ALL-UNNAMED</arg>
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.file=ALL-UNNAMED</arg>
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.main=ALL-UNNAMED</arg>
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.model=ALL-UNNAMED</arg>
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED</arg>
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.processing=ALL-UNNAMED</arg>
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.tree=ALL-UNNAMED</arg>
						<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.util=ALL-UNNAMED</arg>
						<arg>-J--add-opens=jdk.compiler/com.sun.tools.javac.comp=ALL-UNNAMED</arg>
					</compilerArgs>
					<annotationProcessorPaths>
						<path>
							<groupId>org.checkerframework</groupId>
							<artifactId>checker</artifactId>
							<version>3.50.0</version>
						</path>
					</annotationProcessorPaths>
					<annotationProcessors>
						<annotationProcessor>org.checkerframework.checker.nullness.NullnessChecker</annotationProcessor>
					</annotationProcessors>
					<!-- /Needed for checkerframework -->
				</configuration>
			</plugin>

		</plugins>
	</build>

</project>

[mernst]

This is a duplicate of #7241 and #7248.
Please provide --add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED along with any other --add-exports in the Checker Framework invocation.
(This is a new requirement. We erred by omitting it from the changelog.)

[DrMicrobit]

I am not sure it is an exact duplicate. The pom.xml I initially pasted contains this in line 44:
<arg>-J--add-exports=jdk.compiler/com.sun.tools.javac.parser=ALL-UNNAMED</arg>

Which, after double-checking, is the add export you suggested (with the needed -J in front).

The whole <compilerArgs> block in my pom.xml was copied from the <jdk>[9,)</jdk> part at https://checkerframework.org/manual/#maven this morning, including the javac.parser export.

I am sorry, but I am still getting the error.

[DrMicrobit]

Addendum: I just tried 3.49.5 and I am getting the same error. So this is not a 3.50.0 thing, I am sorry to have misreported this in the title of this issue.

[mernst]

Thanks for the clarification, and I apologize for not reading carefully enough to see that the issue was different.
I can reproduce the problem, using the minimal example you provided. (Thanks! Such an example is extremely helpful.)

would it be possible for the checkerframework to include a fully developed toy project for a maven integration?

The Maven section in the manual says:
"See the directory docs/examples/MavenExample/ for examples of the use of Maven build files."

By comparing that with your pom.xml file, I found that yours was missing this line:

              <fork>true</fork> <!-- Must fork or else JVM arguments are ignored. -->

When I added that, your example worked. Could you please try, and close this issue if it works for you?

[DrMicrobit]

Works.

Ouch, totally my bad. My eye glanced over both the "See the directory ..." part of the help text as well as the comment for the fork tag in the configuration part of the plugin.

Thank you for your time to help resolve this.

Time being at a premium, would you accept a PR that tries to remedy the "glance over" effect for future readers if I made one? In "external-tools.tex" and a few other files, I would replace \code references to specific supplied examples by a \href (or \ahreforurl ?) pointing directly to the examples on GitHub. Additionally I'd make the fork tag plus warning stand out more prominently in the pom.xml.

[mernst]

Yes, we would accept a pull request. Thanks in advance!
I did already make an improvement at #7260, but perhaps further enhancements to the documentation would be useful.