bwjoh opened a new issue, #3013:
URL: https://github.com/apache/parquet-java/issues/3013
### Describe the bug, including details regarding any error messages,
version, and platform.
Noticed when upgrading from 1.13.1 to 1.14.1
```
java.lang.ClassCastException: class
org.apache.parquet.column.values.dictionary.DictionaryValuesReader cannot be
cast to class
org.apache.parquet.column.values.deltastrings.DeltaByteArrayReader
(org.apache.parquet.column.values.dictionary.DictionaryValuesReader and
org.apache.parquet.column.values.deltastrings.DeltaByteArrayReader are in
unnamed module of loader 'app')
at
org.apache.parquet.column.values.deltastrings.DeltaByteArrayReader.setPreviousReader(DeltaByteArrayReader.java:92)
at
org.apache.parquet.column.impl.ColumnReaderBase.initDataReader(ColumnReaderBase.java:734)
at
org.apache.parquet.column.impl.ColumnReaderBase.readPageV2(ColumnReaderBase.java:766)
at
org.apache.parquet.column.impl.ColumnReaderBase.access$400(ColumnReaderBase.java:56)
at
org.apache.parquet.column.impl.ColumnReaderBase$3.visit(ColumnReaderBase.java:695)
at
org.apache.parquet.column.impl.ColumnReaderBase$3.visit(ColumnReaderBase.java:686)
at org.apache.parquet.column.page.DataPageV2.accept(DataPageV2.java:232)
at
org.apache.parquet.column.impl.ColumnReaderBase.readPage(ColumnReaderBase.java:686)
at
org.apache.parquet.column.impl.ColumnReaderBase.checkRead(ColumnReaderBase.java:660)
at
org.apache.parquet.column.impl.ColumnReaderBase.consume(ColumnReaderBase.java:802)
at
org.apache.parquet.column.impl.ColumnReaderImpl.consume(ColumnReaderImpl.java:30)
at
org.apache.parquet.io.RecordReaderImplementation.read(RecordReaderImplementation.java:427)
```
This appears to be due to PARQUET-2431 -
https://github.com/apache/parquet-java/pull/1274/files#diff-362b7d44b24283c1bb1f6ca3e124cb72706a33ed96d86b58bf3339f20aafb4e9R732
Looking into how my code hit this and it seems to be that
`CorruptDeltaByteArrays.requiresSequentialReads` was essentially doing the
`dataColumn instanceof RequiresPreviousReader` check previously
(`CorruptDeltaByteArrays.requiresSequentialReads` can only return true when
`encoding == Encoding.DELTA_BYTE_ARRAY`, and
`org.apache.parquet.column.values.RequiresPreviousReader` is only implemented
by *DeltaByteArrayReader classes).
With no check on `previousReader instanceof RequiresPreviousReader` the
ClassCastException is possible above.
This is more likely to happen when using
`org.apache.parquet.io.ColumnIOFactory#ColumnIOFactory()` to read files without
`createdBy`. In my case I was able to fix this by adding createdBy, knowing
that all Parquet files I have were written after PARQUET-246, which prevents
`CorruptDeltaByteArrays.requiresSequentialReads` from returning true
```
val reader: ParquetFileReader = ...
val fileMetadata = reader.getFooter.getFileMetaData
val createdBy = fileMetadata.getCreatedBy
val columnIO: MessageColumnIO = new ColumnIOFactory(createdBy)...
```
### Component(s)
_No response_
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