Is there a way to configure Java heap size for the docker container?

When I run openapi-generator-cli on a large OpenAPI file with useDocker, I get the following error when generating Java code:

Exception in thread "main" java.lang.OutOfMemoryError: Java heap space
	at java.base/java.util.Arrays.copyOf(Unknown Source)
	at java.base/java.lang.AbstractStringBuilder.ensureCapacityInternal(Unknown Source)
	at java.base/java.lang.AbstractStringBuilder.append(Unknown Source)
	at java.base/java.lang.StringBuffer.append(Unknown Source)
	at java.base/java.io.StringWriter.write(Unknown Source)
	at com.samskivert.mustache.Template$Segment.write(Template.java:369)
	at com.samskivert.mustache.Mustache$StringSegment.execute(Mustache.java:718)
	at com.samskivert.mustache.Template.executeSegs(Template.java:157)
	at com.samskivert.mustache.Template.execute(Template.java:134)
	at com.samskivert.mustache.Template.execute(Template.java:125)
	at org.openapitools.codegen.templating.MustacheEngineAdapter.compileTemplate(MustacheEngineAdapter.java:65)
	at org.openapitools.codegen.TemplateManager.write(TemplateManager.java:163)
	at org.openapitools.codegen.DefaultGenerator.processTemplateToFile(DefaultGenerator.java:1058)
	at org.openapitools.codegen.DefaultGenerator.processTemplateToFile(DefaultGenerator.java:1045)
	at org.openapitools.codegen.DefaultGenerator.generateSupportingFiles(DefaultGenerator.java:738)
	at org.openapitools.codegen.DefaultGenerator.generate(DefaultGenerator.java:919)
	at org.openapitools.codegen.cmd.Generate.execute(Generate.java:465)
	at org.openapitools.codegen.cmd.OpenApiGeneratorCommand.run(OpenApiGeneratorCommand.java:32)
	at org.openapitools.codegen.OpenAPIGenerator.main(OpenAPIGenerator.java:66)

Other languages work fine, and I suspect I just need to give the Java heap some more memory. However, when I look at https://github.com/OpenAPITools/openapi-generator-cli/blob/f3f431db8080a57f788adedd09e2e1aa52ee07b3/apps/generator-cli/src/app/services/pass-through.service.ts#L119-L124, it doesn't appear there's any way to pass in JAVA_OPTS="-Xmx4g" or similar.

Am I missing something? Is there any way to set the max Java heap size?

Start at apps/generator-cli/src/app/services/pass-through.service.ts around lines 119-124 and trace how useDocker launches the generator. Confirm whether Java options can be passed through; done means documenting or exposing a heap-size setting and verifying generation of a large Java project without the reported error.