apache / apache/parquet-java

ParquetReader.read(InputFile) always causes exception on build

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Component: Parquet Priority: Major Type: bug
Dominant language
Java
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Description

The [`ParquetReader.read(InputFile file)`](https://www.javadoc.io/static/org.apache.parquet/parquet-hadoop/1.11.1/org/apache/parquet/hadoop/ParquetReader.html#read-org.apache.parquet.io.InputFile-) static factory method in `parquet-hadoop` creates a builder from an `InputFile`.  This method always throws an `IllegalArgumentException` when `.build()` is subsequently called.
```java

java.nio.Path parquetFile = getParquetFile();
ParquetReader.read(HadoopInputFile.fromPath(new org.apache.hadoop.fs.Path(parquetFile.toUri()), new Configuration()))
.build();
```
```

java.lang.IllegalArgumentException: [BUG] Classes that extend Builder should override getReadSupport()

at org.apache.parquet.Preconditions.checkArgument(Preconditions.java:53)
at org.apache.parquet.hadoop.ParquetReader$Builder.getReadSupport(ParquetReader.java:310)
at org.apache.parquet.hadoop.ParquetReader$Builder.build(ParquetReader.java:337)
```
The issue appears to be that the [`build()`](https://www.javadoc.io/static/org.apache.parquet/parquet-hadoop/1.11.1/org/apache/parquet/hadoop/ParquetReader.Builder.html#build--) method enforces that a [`ReadSupport`](https://www.javadoc.io/static/org.apache.parquet/parquet-hadoop/1.11.1/org/apache/parquet/hadoop/api/ReadSupport.html) value was set on the builder, but `ParquetReader.read(InputFile file)` doesn't take accept a `ReadSupport`, nor is there a way to set it after the builder has been created.

For context, my use case is reading Parquet files directly from Java.
## Expected behavior

I wouldn't expect a method to exist that always results in an exception being thrown. I would expect the `ParquetReader.read(InputFile file)` to be fixed, replaced, or removed.
## Workaround

I am able to achieve my goal by using [`ParquetFileReader.open(InputFile)`](https://www.javadoc.io/static/org.apache.parquet/parquet-hadoop/1.11.1/org/apache/parquet/hadoop/ParquetFileReader.html#open-org.apache.parquet.io.InputFile-) instead of `ParquetReader.read(InputFile)`.
```java

java.nio.Path parquetFile = getParquetFile();
ParquetFileReader reader = ParquetFileReader.open(
HadoopInputFile.fromPath(new org.apache.hadoop.fs.Path(parquetFile.toUri()), new Configuration()));
```

**Reporter**: [M. Justin](https://issues.apache.org/jira/secure/ViewProfile.jspa?name=mjjustin)

**Note**: *This issue was originally created as [PARQUET-1912](https://issues.apache.org/jira/browse/PARQUET-1912). Please see the [migration documentation](https://issues.apache.org/jira/browse/PARQUET-2502) for further details.*

Contributor guide

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Research direction

Start with ParquetReader.read(InputFile), then follow the returned Builder into build() and its getReadSupport() check. Reproduce the failure with HadoopInputFile.fromPath and compare it with the working ParquetFileReader.open(InputFile) path. Done means the documented factory no longer fails immediately, with behavior covered by a regression test.

Written by the indexing model from the issue text.

Assessment

Tech stack
java
Domain
data
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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