René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"IllegalArgumentException when starting a QueryBatcher","articleBody":"When we run our integration test-suite especially the tests using the DataMovementManager and a QueryBatcher. The LinkedBlockingQueue used in QueryBatcherImpl#QueryThreadPoolExecutor (QueryBatcherImpl line 1132) is throwing an IllegalArgumentException because the poolSize is calculated to be -1. The line in question is QueryBatcherImpl#1132:\n```\nnew LinkedBlockingQueue\u003c\u003e((forestsLength * docToUriBatchRatio * 2) +  threadCount)\n```\nwith forestsLength=1, **docToUriBatchRatio=-1**, threadCount=1\n\nIt is wierd that `docToUriBatchRatio` is -1. Having a look at QueryBatcherImpl#withBatchSize (line 296), which is called in our case:\n```\npublic QueryBatcher withBatchSize(int docBatchSize) {\n    if (docBatchSize \u003e this.maxUriBatchSize) {\n      logger.debug(\"docBatchSize is beyond maxDocBatchSize, which is {}.\", this.maxUriBatchSize);\n    }\n    if (docBatchSize \u003c 1) {\n      throw new IllegalArgumentException(\"docBatchSize cannot be less than 1\");\n    }\n    requireNotStarted();\n    super.withBatchSize(docBatchSize);\n    this.docToUriBatchRatio = Math.min(this.maxDocToUriBatchRatio, this.maxUriBatchSize / docBatchSize);\n    if (this.docToUriBatchRatio == 0) {\n      this.docToUriBatchRatio = 1;\n    }\n    return this;\n  }\n```\nit happens in line 305 due to maxDocToUriBatchRatio being -1. This -1 is taken from the forest-response given by the MarkLogic server in DataMovementServices#initConfig (line 64). (The else-branch in line 67 is not visited in our case.)\n\nSolutions:\nIt feels like the maxDocToUriBatchRatio=-1 given by the MarkLogic server is supposed to mean something like \"undefined\" or \"unlimited\". Using the -1 in the calculation for the thread pool size seems oddly wrong. If so intended, we would appreciate a proper error message like \"QueryBatcher can not be started ...\". Currently just an IllegalArgumentException without any message is thrown by the Java's native LinkedBlockingQueue.","author":{"url":"https://github.com/ralfhergert","@type":"Person","name":"ralfhergert"},"datePublished":"2026-01-02T16:18:41.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":8},"url":"https://github.com/1872/java-client-api/issues/1872"}