## What changes were proposed in this pull request?
This PR proposes to
- improve the R-friendly error messages rather than raw JVM exception one.
As `read.json`, `read.text`, `read.orc`, `read.parquet` and `read.jdbc` are executed in the same path with `read.df`, and `write.json`, `write.text`, `write.orc`, `write.parquet` and `write.jdbc` shares the same path with `write.df`, it seems it is safe to call `handledCallJMethod` to handle
JVM messages.
- prevent `zero-length variable name` and prints the ignored options as an warning message.
**Before**
``` r
> read.json("path", a = 1, 2, 3, "a")
Error in env[[name]] <- value :
zero-length variable name
```
``` r
> read.json("arbitrary_path")
Error in invokeJava(isStatic = FALSE, objId$id, methodName, ...) :
org.apache.spark.sql.AnalysisException: Path does not exist: file:/...;
at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$12.apply(DataSource.scala:398)
...
> read.orc("arbitrary_path")
Error in invokeJava(isStatic = FALSE, objId$id, methodName, ...) :
org.apache.spark.sql.AnalysisException: Path does not exist: file:/...;
at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$12.apply(DataSource.scala:398)
...
> read.text("arbitrary_path")
Error in invokeJava(isStatic = FALSE, objId$id, methodName, ...) :
org.apache.spark.sql.AnalysisException: Path does not exist: file:/...;
at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$12.apply(DataSource.scala:398)
...
> read.parquet("arbitrary_path")
Error in invokeJava(isStatic = FALSE, objId$id, methodName, ...) :
org.apache.spark.sql.AnalysisException: Path does not exist: file:/...;
at org.apache.spark.sql.execution.datasources.DataSource$$anonfun$12.apply(DataSource.scala:398)
...
```
``` r
> write.json(df, "existing_path")
Error in invokeJava(isStatic = FALSE, objId$id, methodName, ...) :
org.apache.spark.sql.AnalysisException: path file:/... already exists.;
at org.apache.spark.sql.execution.datasources.InsertIntoHadoopFsRelationCommand.run(InsertIntoHadoopFsRelationCommand.scala:68)
> write.orc(df, "existing_path")
Error in invokeJava(isStatic = FALSE, objId$id, methodName, ...) :
org.apache.spark.sql.AnalysisException: path file:/... already exists.;
at org.apache.spark.sql.execution.datasources.InsertIntoHadoopFsRelationCommand.run(InsertIntoHadoopFsRelationCommand.scala:68)
> write.text(df, "existing_path")
Error in invokeJava(isStatic = FALSE, objId$id, methodName, ...) :
org.apache.spark.sql.AnalysisException: path file:/... already exists.;
at org.apache.spark.sql.execution.datasources.InsertIntoHadoopFsRelationCommand.run(InsertIntoHadoopFsRelationCommand.scala:68)
> write.parquet(df, "existing_path")
Error in invokeJava(isStatic = FALSE, objId$id, methodName, ...) :
org.apache.spark.sql.AnalysisException: path file:/... already exists.;
at org.apache.spark.sql.execution.datasources.InsertIntoHadoopFsRelationCommand.run(InsertIntoHadoopFsRelationCommand.scala:68)
```
**After**
``` r
read.json("arbitrary_path", a = 1, 2, 3, "a")
Unnamed arguments ignored: 2, 3, a.
```
``` r
> read.json("arbitrary_path")
Error in json : analysis error - Path does not exist: file:/...
> read.orc("arbitrary_path")
Error in orc : analysis error - Path does not exist: file:/...
> read.text("arbitrary_path")
Error in text : analysis error - Path does not exist: file:/...
> read.parquet("arbitrary_path")
Error in parquet : analysis error - Path does not exist: file:/...
```
``` r
> write.json(df, "existing_path")
Error in json : analysis error - path file:/... already exists.;
> write.orc(df, "existing_path")
Error in orc : analysis error - path file:/... already exists.;
> write.text(df, "existing_path")
Error in text : analysis error - path file:/... already exists.;
> write.parquet(df, "existing_path")
Error in parquet : analysis error - path file:/... already exists.;
```
## How was this patch tested?
Unit tests in `test_utils.R` and `test_sparkSQL.R`.
Author: hyukjinkwon <gurwls223@gmail.com>
Closes#15608 from HyukjinKwon/SPARK-17838.
1ecfafa086