Summary of issue: A field that is nullable is nondeterministically having a null check in the generated code, depending on what other build tasks occurred.
See https://lists.apache.org/thread/cdw4y50r3hl37z8y7x470m2mddclkqgv (from here you can gather more info from the thread)
Inline, paraphrasing the thread...
To reproduce:
git clone https://github.com/apache/beam
cd beam
git checkout 4ffeae4d2b800f2df36d2ea2eab549f2204d5691~1
./gradlew :runners:direct-java:compileJava
less
./runners/direct-java/build/generated/sources/annotationProcessor/java/main/org/apache/beam/runners/direct/AutoValue_ImmutableListBundleFactory_CommittedImmutableListBundle.java
git checkout 4ffeae4d2b800f2df36d2ea2eab549f2204d5691
./gradlew :runners:direct-java:compileJava
less
./runners/direct-java/build/generated/sources/annotationProcessor/java/main/org/apache/beam/runners/direct/AutoValue_ImmutableListBundleFactory_CommittedImmutableListBundle.java
./gradlew :runners:direct-java:compileJava --rerun-tasks
less
./runners/direct-java/build/generated/sources/annotationProcessor/java/main/org/apache/beam/runners/direct/AutoValue_ImmutableListBundleFactory_CommittedImmutableListBundle.java
The class at https://github.com/apache/beam/blob/1dff59b4ff26310f88f927edfcf44709ed6ea9c2/runners/direct-java/src/main/java/org/apache/beam/runners/direct/ImmutableListBundleFactory.java#L130
abstract static class CommittedImmutableListBundle<T> implements CommittedBundle<T> {
public static <T> CommittedImmutableListBundle<T> create(
@Nullable PCollection<T> pcollection,
StructuralKey<?> key,
Iterable<WindowedValue<T>> committedElements,
Instant minElementTimestamp,
Instant synchronizedCompletionTime) {
return new AutoValue_ImmutableListBundleFactory_CommittedImmutableListBundle<>(
pcollection, key, committedElements, minElementTimestamp, synchronizedCompletionTime);
}
...
}
extends https://github.com/apache/beam/blob/1dff59b4ff26310f88f927edfcf44709ed6ea9c2/runners/direct-java/src/main/java/org/apache/beam/runners/direct/CommittedBundle.java#L35
interface CommittedBundle<T> extends Bundle<T, PCollection<T>> {
/** Returns the PCollection that the elements of this bundle belong to. */
@Override
@Nullable
PCollection<T> getPCollection();
...
}
In all cases the PCollection
field should be nullable.
In a "good" build, the AutoValue generated code constructor does not check for null
AutoValue_ImmutableListBundleFactory_CommittedImmutableListBundle(
@Nullable PCollection<T> PCollection,
StructuralKey<?> key,
Iterable<WindowedValue<T>> elements,
Instant minimumTimestamp,
Instant synchronizedProcessingOutputWatermark) {
this.PCollection = PCollection;
in a 'bad' build, the autovalue java is re-generated, but has an added nullness check:
AutoValue_ImmutableListBundleFactory_CommittedImmutableListBundle(
PCollection<T> PCollection,
StructuralKey<?> key,
Iterable<WindowedValue<T>> elements,
Instant minimumTimestamp,
Instant synchronizedProcessingOutputWatermark) {
if (PCollection == null) {
throw new NullPointerException("Null PCollection");
}
this.PCollection = PCollection;
and then with --rerun-tasks
it gets re-re-generated without the nullness check.
type=defect Component: value P3