annotation null pointer exception when List is used as @JsonField in Eclipse

[zhaojiac]

The exception from the Eclipse .log file is as follows:

!ENTRY org.eclipse.jdt.apt.pluggable.core 1 1 2015-01-27 00:48:04.922
!MESSAGE annotation exception: java.lang.NullPointerException cause: java.lang.NullPointerException
at java.util.regex.Matcher.getTextLength(Matcher.java:1234)
at java.util.regex.Matcher.reset(Matcher.java:308)
at java.util.regex.Matcher.(Matcher.java:228)
at java.util.regex.Pattern.matcher(Pattern.java:1088)
at java.util.Formatter.parse(Formatter.java:2515)
at java.util.Formatter.format(Formatter.java:2469)
at java.util.Formatter.format(Formatter.java:2423)
at java.lang.String.format(String.java:2790)
at com.instagram.javawriter.JavaWriter.emitStatement(JavaWriter.java:663)
at com.instagram.common.json.annotation.processor.JsonParserClassData.writeSerializeCalls(JsonParserClassData.java:514)
at com.instagram.common.json.annotation.processor.JsonParserClassData.access$200(JsonParserClassData.java:39)
at com.instagram.common.json.annotation.processor.JsonParserClassData$2.emitJava(JsonParserClassData.java:199)
at com.instagram.javawriter.JavaWriter.emitWithGenerator(JavaWriter.java:72)
at com.instagram.common.json.annotation.processor.JsonParserClassData.getJavaCode(JsonParserClassData.java:183)
at com.instagram.common.json.annotation.processor.JsonAnnotationProcessor.process(JsonAnnotationProcessor.java:101)
at org.eclipse.jdt.internal.compiler.apt.dispatch.RoundDispatcher.handleProcessor(RoundDispatcher.java:139)
at org.eclipse.jdt.internal.compiler.apt.dispatch.RoundDispatcher.round(RoundDispatcher.java:121)
at org.eclipse.jdt.internal.compiler.apt.dispatch.BaseAnnotationProcessorManager.processAnnotations(BaseAnnotationProcessorManager.java:159)
at org.eclipse.jdt.internal.apt.pluggable.core.dispatch.IdeAnnotationProcessorManager.processAnnotations(IdeAnnotationProcessorManager.java:134)
at org.eclipse.jdt.internal.compiler.Compiler.processAnnotations(Compiler.java:820)
at org.eclipse.jdt.internal.compiler.Compiler.compile(Compiler.java:434)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:366)
at org.eclipse.jdt.internal.core.builder.IncrementalImageBuilder.compile(IncrementalImageBuilder.java:329)
at org.eclipse.jdt.internal.core.builder.AbstractImageBuilder.compile(AbstractImageBuilder.java:303)
at org.eclipse.jdt.internal.core.builder.IncrementalImageBuilder.build(IncrementalImageBuilder.java:134)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.buildDeltas(JavaBuilder.java:265)
at org.eclipse.jdt.internal.core.builder.JavaBuilder.build(JavaBuilder.java:193)
at org.eclipse.core.internal.events.BuildManager$2.run(BuildManager.java:733)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:206)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:246)
at org.eclipse.core.internal.events.BuildManager$1.run(BuildManager.java:299)
at org.eclipse.core.runtime.SafeRunner.run(SafeRunner.java:42)
at org.eclipse.core.internal.events.BuildManager.basicBuild(BuildManager.java:302)
at org.eclipse.core.internal.events.BuildManager.basicBuildLoop(BuildManager.java:358)
at org.eclipse.core.internal.events.BuildManager.build(BuildManager.java:381)
at org.eclipse.core.internal.events.AutoBuildJob.doBuild(AutoBuildJob.java:143)
at org.eclipse.core.internal.events.AutoBuildJob.run(AutoBuildJob.java:241)
at org.eclipse.core.internal.jobs.Worker.run(Worker.java:53)

[ttung]

is this a transient issue due to incremental compilation?

[zhaojiac]

@ttung Doesn't seem to be.... I tried to clean the project and rebuild which doesn't solve the issue.

[ttung]

Oh! Is your List type parameterized? It needs to be:

List<SomeType> foo;

SomeType either needs to be a type annotated with @jsontype or it needs to be an autoboxed primitive (like Integer, Float, etc)

[ttung]

Did that solve your problem, btw?

[zhaojiac]

@ttung Thanks for the reply. It doesn't solve the issue. My List definitions are type parameterized. But you mention that it needs to be type annoated with @jsontype or primitives..... So Java class like String wouldn't work ?

[ttung]

Strings should work.

Do you get any errors when you build?

[kangzhang]

@zhaojiac

Did you use guava's ImmutableList or some other List type that our parser can't handle? (Another user who hit similar exception used guava's ImmutablaList, I'm wondering if it's the case for you)

It would be helpful if you can paste your model class here so that we can repro the issue. I'd be happy to take a look.

[ghost]

Thank you for reporting this issue and appreciate your patience. We've notified the core team for an update on this issue. We're looking for a response within the next 30 days or the issue may be closed.