Apache Parquet Java
This report presents the forensic synthetic code analysis of apache/parquet-java, a Java project with 3,065 GitHub stars. SynthScan v2.0 examined 207,873 lines of code across 937 source files, recording 102 pattern matches distributed across 5 syntactic categories. The overall adjusted score of 4.3 places this repository in the Likely human-written band.
The scanner applied 160+ deterministic lexical heuristics, multi-line block detectors, abstract syntax tree depth profilers, and a cross-file Jaccard similarity matrix to construct a statistically normalised synthetic code estimate. All matches are individually weighted by severity coefficient and contextual multiplier before summation, and the resulting headline score is temporally discounted to account for the repository's development history relative to the commercial emergence of large language model coding tooling (November 2022 onward).
Longitudinal tracking requires multiple scan runs. Once this repository is re-scanned after new commits land, this chart will visualise how the synthetic code signal evolves over time — enabling you to detect whether AI authorship is growing, stabilising, or being actively corrected by human engineers.
Classifies detected patterns by their diagnostic confidence and structural impact. CRITICAL patterns (coefficient 10) represent definitive synthetic signatures — hallucinated imports, explicit LLM attribution metadata — virtually never produced by human authors. HIGH (5) indicates strong structural tells such as cross-file repetition or cross-linguistic idioms. MEDIUM (2) covers recognisable conversational padding and AI-specific vocabulary. LOW (1) captures subtle indicators like tautological comments and generic boilerplate that require density to carry independent signal.
This horizontal bar chart decomposes the repository's raw synthetic code score by top-level directory, allowing you to pinpoint precisely which modules or components carry the highest AI authorship density. Directories with disproportionately high scores relative to their size warrant targeted manual review: concentrated AI signatures often trace back to mass-generated configuration layers, auto-ported test suites, LLM-scaffolded boilerplate classes, or entire subsystems authored under heavy copilot assistance. Use this view to prioritise your human code-review effort.
The scanner identified 102 distinct pattern matches across 5 syntactic categories. Each entry below represents a discrete location in the source code where the engine recorded a statistically significant AI authorship indicator. Expand any category row to inspect the individual file paths, line numbers, code snippets, and the lexical context (CODE, COMMENT, or STRING) in which each match was detected.
Reading the findings table: The Severity column indicates the diagnostic confidence level (CRITICAL / HIGH / MEDIUM / LOW). The Context column identifies whether the match occurred inside executable code, an inline comment, or a string literal — comment-context matches receive a ×1.5 weight because LLMs systematically over-annotate. The ⚡ bolt icon marks clustered matches: three or more patterns within a 10-line window, each receiving an additional ×1.5 density multiplier as dense clusters constitute far stronger evidence of synthetic authorship than isolated hits.
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| CRITICAL⚡ | …a/org/apache/parquet/avro/TestAvroRecordConverter.java | 150 | // MODEL$.addLogicalTypeConversion(new org.apache.avro.data.TimeConversions.TimestampMillisConversion()); | COMMENT |
| CRITICAL⚡ | …a/org/apache/parquet/avro/TestAvroRecordConverter.java | 151 | // MODEL$.addLogicalTypeConversion(new org.apache.avro.data.TimeConversions.TimeMillisConversion()); | COMMENT |
| CRITICAL⚡ | …a/org/apache/parquet/avro/TestAvroRecordConverter.java | 155 | new org.apache.avro.data.TimeConversions.DateConversion(), | CODE |
| CRITICAL⚡ | …a/org/apache/parquet/avro/TestAvroRecordConverter.java | 156 | new org.apache.avro.data.TimeConversions.TimeMillisConversion(), | CODE |
| CRITICAL⚡ | …a/org/apache/parquet/avro/TestAvroRecordConverter.java | 185 | // MODEL$.addLogicalTypeConversion(new org.apache.avro.data.TimeConversions.DateConversion()); | COMMENT |
| CRITICAL⚡ | …a/org/apache/parquet/avro/TestAvroRecordConverter.java | 186 | // MODEL$.addLogicalTypeConversion(new org.apache.avro.data.TimeConversions.TimestampMillisConversion()); | COMMENT |
| CRITICAL⚡ | …a/org/apache/parquet/avro/TestAvroRecordConverter.java | 187 | // MODEL$.addLogicalTypeConversion(new org.apache.avro.data.TimeConversions.TimeMillisConversion()); | COMMENT |
| CRITICAL⚡ | …a/org/apache/parquet/avro/TestAvroRecordConverter.java | 191 | new org.apache.avro.data.TimeConversions.TimestampMillisConversion(), null, null | CODE |
| CRITICAL | …t/java/org/apache/parquet/avro/TestStringBehavior.java | 178 | avroFile, new SpecificDatumReader<>(org.apache.parquet.avro.StringBehaviorTest.getClassSchema()))) { | CODE |
| CRITICAL | …t/java/org/apache/parquet/avro/TestStringBehavior.java | 359 | AvroReadSupport.setAvroReadSchema(conf, org.apache.parquet.avro.StringBehaviorTest.getClassSchema()); | CODE |
| CRITICAL | …/thrift/TestParquetToThriftReadWriteAndProjection.java | 295 | new RequiredListFixture(Arrays.asList(new org.apache.parquet.thrift.test.Name("first_name"))); | CODE |
| CRITICAL | …/thrift/TestParquetToThriftReadWriteAndProjection.java | 309 | Arrays.asList(new org.apache.parquet.thrift.test.Name("first_name")))); | CODE |
| CRITICAL | …quet/filter2/statisticslevel/TestStatisticsFilter.java | 114 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading( | CODE |
| CRITICAL | …quet/filter2/statisticslevel/TestStatisticsFilter.java | 119 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading( | CODE |
| CRITICAL | …quet/filter2/statisticslevel/TestStatisticsFilter.java | 400 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading( | CODE |
| CRITICAL | …quet/filter2/statisticslevel/TestStatisticsFilter.java | 745 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading( | CODE |
| CRITICAL | …quet/filter2/statisticslevel/TestStatisticsFilter.java | 798 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading(ieee754Type) | CODE |
| CRITICAL | …quet/filter2/statisticslevel/TestStatisticsFilter.java | 953 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading(FLOAT16_TYPE) | CODE |
| CRITICAL | …quet/filter2/statisticslevel/TestStatisticsFilter.java | 982 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading(FLOAT16_TYPE) | CODE |
| CRITICAL | …quet/filter2/statisticslevel/TestStatisticsFilter.java | 1013 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading(FLOAT16_TYPE) | CODE |
| CRITICAL | …quet/filter2/dictionarylevel/DictionaryFilterTest.java | 649 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading(type) | CODE |
| CRITICAL | …a/org/apache/parquet/hadoop/TestParquetFileWriter.java | 154 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading( | CODE |
| CRITICAL | …a/org/apache/parquet/hadoop/TestParquetFileWriter.java | 870 | org.apache.parquet.format.converter.ParquetMetadataConverter.toParquetStatistics(parquetMRstats); | CODE |
| CRITICAL | …a/org/apache/parquet/hadoop/TestParquetFileWriter.java | 872 | (LongStatistics) org.apache.parquet.format.converter.ParquetMetadataConverter.fromParquetStatistics( | CODE |
| CRITICAL | …a/org/apache/parquet/hadoop/TestParquetFileWriter.java | 1144 | return org.apache.parquet.column.statistics.Statistics.getBuilderForReading(col.getPrimitiveType()) | CODE |
| CRITICAL | …a/org/apache/parquet/hadoop/TestParquetFileWriter.java | 1503 | org.apache.parquet.column.statistics.Statistics.createStats(C1.getPrimitiveType()); | CODE |
| CRITICAL | …a/org/apache/parquet/hadoop/TestParquetFileWriter.java | 1516 | org.apache.parquet.column.statistics.Statistics.createStats(C2.getPrimitiveType()); | CODE |
| CRITICAL | …he/parquet/hadoop/TestInputFormatColumnProjection.java | 127 | org.apache.hadoop.mapreduce.JobContext.class.isInterface()); | CODE |
| CRITICAL | …g/apache/parquet/hadoop/DeprecatedInputFormatTest.java | 124 | org.apache.hadoop.mapred.TextOutputFormat.setOutputPath(jobConf, outputPath); | CODE |
| CRITICAL | …g/apache/parquet/hadoop/DeprecatedInputFormatTest.java | 246 | org.apache.hadoop.mapred.FileInputFormat.setInputPaths(conf, new Path(inputDir.toURI())); | CODE |
| CRITICAL | …g/apache/parquet/hadoop/DeprecatedInputFormatTest.java | 247 | org.apache.hadoop.mapred.TextOutputFormat.setOutputPath(conf, new Path(outputDir.toURI())); | CODE |
| CRITICAL⚡ | …ache/parquet/hadoop/example/TestInputOutputFormat.java | 352 | Method getGroup = org.apache.hadoop.mapreduce.Counters.class.getMethod("getGroup", String.class); | CODE |
| CRITICAL⚡ | …ache/parquet/hadoop/example/TestInputOutputFormat.java | 354 | Method findCounter = org.apache.hadoop.mapreduce.CounterGroup.class.getMethod("findCounter", String.class); | CODE |
| CRITICAL⚡ | …ache/parquet/hadoop/example/TestInputOutputFormat.java | 356 | Method getValue = org.apache.hadoop.mapreduce.Counter.class.getMethod("getValue"); | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 473 | for (org.apache.parquet.column.Encoding encoding : org.apache.parquet.column.Encoding.values()) { | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 477 | for (org.apache.parquet.format.Encoding encoding : org.apache.parquet.format.Encoding.values()) { | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 661 | new org.apache.parquet.hadoop.metadata.FileMetaData( | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 688 | new org.apache.parquet.hadoop.metadata.FileMetaData( | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 767 | new HashSet<>(Arrays.asList(org.apache.parquet.column.Encoding.values())); | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 1326 | new org.apache.parquet.hadoop.metadata.FileMetaData(schema, new HashMap<String, String>(), null); | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 1394 | new org.apache.parquet.hadoop.metadata.FileMetaData(schema, new HashMap<String, String>(), null); | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 1832 | new org.apache.parquet.column.statistics.geospatial.BoundingBox( | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 1845 | new org.apache.parquet.column.statistics.geospatial.GeospatialStatistics(bbox, geospatialTypes); | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 1914 | new org.apache.parquet.column.statistics.geospatial.GeospatialStatistics(null, geospatialTypes); | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 1945 | new org.apache.parquet.column.statistics.geospatial.BoundingBox( | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 1956 | new org.apache.parquet.column.statistics.geospatial.GeospatialStatistics(invalidBbox, null); | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 1994 | new org.apache.parquet.hadoop.metadata.FileMetaData(schema, new HashMap<String, String>(), null); | CODE |
| CRITICAL | …uet/format/converter/TestParquetMetadataConverter.java | 2031 | new org.apache.parquet.hadoop.metadata.FileMetaData(schema, new HashMap<String, String>(), null); | CODE |
| CRITICAL | …org/apache/parquet/hadoop/rewrite/ParquetRewriter.java | 811 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading(type); | CODE |
| CRITICAL | …/java/org/apache/parquet/hadoop/codec/CodecConfig.java | 160 | return org.apache.hadoop.mapred.FileOutputFormat.getCompressOutput(conf); | CODE |
| CRITICAL | …/java/org/apache/parquet/hadoop/codec/CodecConfig.java | 165 | return org.apache.hadoop.mapred.FileOutputFormat.getOutputCompressorClass(conf, defaultCodec); | CODE |
| CRITICAL | …/org/apache/parquet/hadoop/codec/Lz4RawCompressor.java | 31 | return io.airlift.compress.lz4.Lz4RawCompressor.maxCompressedLength(byteSize); | CODE |
| CRITICAL | …parquet/format/converter/ParquetMetadataConverter.java | 381 | return org.apache.parquet.format.TimeUnit.MICROS(new MicroSeconds()); | CODE |
| CRITICAL | …parquet/format/converter/ParquetMetadataConverter.java | 383 | return org.apache.parquet.format.TimeUnit.MILLIS(new MilliSeconds()); | CODE |
| CRITICAL | …parquet/format/converter/ParquetMetadataConverter.java | 764 | return org.apache.parquet.column.Encoding.valueOf(encoding.name()); | CODE |
| CRITICAL | …parquet/format/converter/ParquetMetadataConverter.java | 952 | org.apache.parquet.column.statistics.Statistics.getBuilderForReading(type); | CODE |
| CRITICAL | …parquet/format/converter/ParquetMetadataConverter.java | 1039 | bbox = new org.apache.parquet.column.statistics.geospatial.BoundingBox( | CODE |
| CRITICAL | …parquet/format/converter/ParquetMetadataConverter.java | 1059 | return new org.apache.parquet.column.statistics.geospatial.GeospatialStatistics(bbox, geospatialTypes); | CODE |
| CRITICAL | …parquet/format/converter/ParquetMetadataConverter.java | 1061 | return new org.apache.parquet.column.statistics.geospatial.GeospatialStatistics( | CODE |
| CRITICAL | …parquet/format/converter/ParquetMetadataConverter.java | 1991 | new org.apache.parquet.hadoop.metadata.FileMetaData( | CODE |
| 11 more matches not shown… | ||||
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| MEDIUM⚡ | …ava/org/apache/parquet/cli/commands/ToAvroCommand.java | 126 | "# Create an Avro file from a Parquet file", | CODE |
| MEDIUM⚡ | …ava/org/apache/parquet/cli/commands/ToAvroCommand.java | 128 | "# Create an Avro file in HDFS from a local JSON file", | CODE |
| MEDIUM⚡ | …ava/org/apache/parquet/cli/commands/ToAvroCommand.java | 130 | "# Create an Avro file from data in S3", | CODE |
| MEDIUM⚡ | …va/org/apache/parquet/cli/commands/ConvertCommand.java | 157 | "# Create a Parquet file from an Avro file", | CODE |
| MEDIUM⚡ | …va/org/apache/parquet/cli/commands/ConvertCommand.java | 159 | "# Create a Parquet file in S3 from a local Avro file", | CODE |
| MEDIUM⚡ | …va/org/apache/parquet/cli/commands/ConvertCommand.java | 161 | "# Create a Parquet file from Avro data in S3", | CODE |
| MEDIUM | …org/apache/parquet/cli/commands/ConvertCSVCommand.java | 203 | "# Create a Parquet file from a CSV file", | CODE |
| MEDIUM | …org/apache/parquet/cli/commands/ConvertCSVCommand.java | 205 | "# Create a Parquet file in HDFS from local CSV", | CODE |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | changelog.sh | 1 | # | COMMENT |
| LOW | .asf.yaml | 1 | # | COMMENT |
| LOW | parquet-benchmarks/run.sh | 1 | #!/usr/bin/env bash | COMMENT |
| LOW | …mn/src/main/java/org/apache/parquet/example/Paper.java | 81 | // Name | COMMENT |
| LOW | …/org/apache/parquet/io/RecordReaderImplementation.java | 101 | COMMENT | |
| LOW | .github/dependabot.yml | 1 | # | COMMENT |
| LOW | .github/workflows/ci-hadoop3.yml | 1 | # Licensed to the Apache Software Foundation (ASF) under one | COMMENT |
| LOW | .github/workflows/stale-prs.yml | 1 | # Licensed to the Apache Software Foundation (ASF) under one | COMMENT |
| LOW | .github/workflows/vector-plugins.yml | 1 | # Licensed to the Apache Software Foundation (ASF) under one | COMMENT |
| LOW | .github/ISSUE_TEMPLATE/config.yaml | 1 | # Licensed to the Apache Software Foundation (ASF) under one | COMMENT |
| LOW | .github/ISSUE_TEMPLATE/usage_question.yaml | 1 | # Licensed to the Apache Software Foundation (ASF) under one | COMMENT |
| LOW | .github/ISSUE_TEMPLATE/bug_report.yaml | 1 | # Licensed to the Apache Software Foundation (ASF) under one | COMMENT |
| LOW | .github/ISSUE_TEMPLATE/feature_request.yaml | 1 | # Licensed to the Apache Software Foundation (ASF) under one | COMMENT |
| LOW | …olumn/values/bitpacking/ByteBitPacking512VectorLE.java | 3181 | // TODO Replace these helpers with ByteVector.fromMemorySegment(...) once the project's minimum | COMMENT |
| LOW | dev/prepare-release.sh | 1 | #!/bin/bash | COMMENT |
| LOW | dev/ci-before_install.sh | 1 | #!/usr/bin/env bash | COMMENT |
| LOW | dev/source-release.sh | 1 | #!/bin/bash | COMMENT |
| LOW | dev/ci-before_install-master.sh | 1 | # Licensed to the Apache Software Foundation (ASF) under one | COMMENT |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| MEDIUM | …ache/parquet/hadoop/UnmaterializableRecordCounter.java | 28 | // Essentially taken from: | COMMENT |
| MEDIUM | parquet-benchmarks/run.sh | 82 | # Actually run a benchmark in the JMH harness. | COMMENT |
| Severity | File | Line | Snippet | Context |
|---|---|---|---|---|
| LOW | …va/org/apache/parquet/cli/commands/CatCommandTest.java | 153 | .append("customer-name", "Jane Doe") | CODE |
| LOW | …e/parquet/cli/commands/ShowBloomFilterCommandTest.java | 91 | phoneCommand.testValues = Arrays.asList(new String[] {"555-0001", "555-9999"}); | CODE |
| LOW | …e/parquet/cli/commands/ShowBloomFilterCommandTest.java | 126 | String[] phoneValues = {"555-0001", "555-0002", "555-0003", "555-0004", "555-0005"}; | CODE |