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Debug: UnsupportedOperationException when cleaning a list

Q: Debug: UnsupportedOperationException when cleaning a list

Root cause subList view does not support structural modification via its own iterator/remove.

JavaCollectionsTrickySenior

Removing inactive IDs crashes at runtime.

Java

List<String> all = repository.findAllIds();
List<String> view = all.subList(0, Math.min(50, all.size()));
for (String id : view) {
    if (isInactive(id)) {
        view.remove(id);
    }
}

Model answerPreview

Root cause

subList view does not support structural modification via its own iterator/remove.