io.delta.kernel.utils

Class Utils

java.lang.Object

io.delta.kernel.utils.Utils

public class Utils
extends java.lang.Object

Constructor Summary

Constructors

Constructor and Description
Utils()

Method Summary

Modifier and Type	Method and Description
static void	closeCloseables(java.io.Closeable... closeables) Close the given one or more Closeables.
static void	closeCloseablesSilently(java.io.Closeable... closeables) Close the given list of Closeable objects.
static java.lang.String	getColumnMappingMode(Row scanState) Get the column mapping mode from the scan state Row returned by Scan.getScanState(TableClient).
static FileStatus	getFileStatus(Row scanFileInfo) Get the FileStatus from given scan file Row.
static StructType	getLogicalSchema(TableClient tableClient, Row scanState) Utility method to get the logical schema from the scan state Row returned by Scan.getScanState(TableClient).
static java.util.List<java.lang.String>	getPartitionColumns(Row scanState) Get the list of partition column names from the scan state Row returned by Scan.getScanState(TableClient).
static java.util.Map<java.lang.String,java.lang.String>	getPartitionValues(Row scanFileInfo) Get the partition columns and value belonging to the given scan file row.
static StructType	getPhysicalSchema(TableClient tableClient, Row scanState) Utility method to get the physical schema from the scan state Row returned by Scan.getScanState(TableClient).
static Row	requireNonNull(Row row, int ordinal, java.lang.String columnName)
static <T> CloseableIterator<T>	singletonCloseableIterator(T elem) Utility method to create a singleton CloseableIterator.
static ColumnVector	singletonColumnVector(java.lang.String value) Utility method to create a singleton string ColumnVector
static <T> CloseableIterator<T>	toCloseableIterator(java.util.Iterator<T> iter) Convert a Iterator to CloseableIterator.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

Utils

public Utils()

Method Detail

singletonCloseableIterator

public static <T> CloseableIterator<T> singletonCloseableIterator(T elem)

Utility method to create a singleton CloseableIterator.

Type Parameters:

T - Element type.

Parameters:

elem - Element to create iterator with.

Returns:

A CloseableIterator with just one element.

toCloseableIterator

public static <T> CloseableIterator<T> toCloseableIterator(java.util.Iterator<T> iter)

Convert a Iterator to CloseableIterator. Useful when passing normal iterators for arguments that require CloseableIterator type.

Type Parameters:

T - Element type

Parameters:

iter - Iterator instance

Returns:

A CloseableIterator wrapping the given Iterator

singletonColumnVector

public static ColumnVector singletonColumnVector(java.lang.String value)

Utility method to create a singleton string ColumnVector

Parameters:

value - the string element to create the vector with

Returns:

A ColumnVector with a single element value

getLogicalSchema

public static StructType getLogicalSchema(TableClient tableClient,
                                          Row scanState)

Utility method to get the logical schema from the scan state Row returned by Scan.getScanState(TableClient).

Parameters:

tableClient - instance of TableClient to use.

scanState - Scan state Row

Returns:

Logical schema to read from the data files.

getPhysicalSchema

public static StructType getPhysicalSchema(TableClient tableClient,
                                           Row scanState)

Utility method to get the physical schema from the scan state Row returned by Scan.getScanState(TableClient).

Parameters:

tableClient - instance of TableClient to use.

scanState - Scan state Row

Returns:

Physical schema to read from the data files.

getPartitionColumns

public static java.util.List<java.lang.String> getPartitionColumns(Row scanState)

Get the list of partition column names from the scan state Row returned by Scan.getScanState(TableClient).

Parameters:

scanState - Scan state Row

Returns:

List of partition column names according to the scan state.

getColumnMappingMode

public static java.lang.String getColumnMappingMode(Row scanState)

Get the column mapping mode from the scan state Row returned by Scan.getScanState(TableClient).

getFileStatus

public static FileStatus getFileStatus(Row scanFileInfo)

Get the FileStatus from given scan file Row. The FileStatus contains file metadata about the scan file.

Parameters:

scanFileInfo - Row representing one scan file.

Returns:

a FileStatus object created from the given scan file row.

getPartitionValues

public static java.util.Map<java.lang.String,java.lang.String> getPartitionValues(Row scanFileInfo)

Get the partition columns and value belonging to the given scan file row.

Parameters:

scanFileInfo - Row representing one scan file.

Returns:

Map of partition column name to partition column value.

closeCloseables

public static void closeCloseables(java.io.Closeable... closeables)

Close the given one or more Closeables. Closeable.close() will be called on all given non-null closeables. Will throw unchecked RuntimeException if an error occurs while closing. If multiple closeables causes exceptions in closing, the exceptions will be added as suppressed to the main exception that is thrown.

Parameters:

closeables -

closeCloseablesSilently

public static void closeCloseablesSilently(java.io.Closeable... closeables)

Close the given list of Closeable objects. Any exception thrown is silently ignored.

Parameters:

closeables -

requireNonNull

public static Row requireNonNull(Row row,
                                 int ordinal,
                                 java.lang.String columnName)