org.apache.calcite.avatica

Class Meta.Frame

java.lang.Object

org.apache.calcite.avatica.Meta.Frame

Enclosing interface:

Meta

public static class Meta.Frame
extends Object

A collection of rows.

Field Summary

Fields

Modifier and Type	Field and Description
boolean	done Whether this is definitely the last frame of rows.
static Meta.Frame	EMPTY Frame that has zero rows and is the last frame.
private static com.google.protobuf.Descriptors.FieldDescriptor	HAS_ARRAY_VALUE_DESCRIPTOR
static Meta.Frame	MORE Frame that has zero rows but may have another frame.
long	offset Zero-based offset of first row.
Iterable<Object>	rows The rows.
private static com.google.protobuf.Descriptors.FieldDescriptor	SCALAR_VALUE_DESCRIPTOR

Constructor Summary

Constructors

Constructor and Description
Frame(long offset, boolean done, Iterable<Object> rows)

Method Summary

Modifier and Type	Method and Description
static Meta.Frame	create(long offset, boolean done, List<Object> rows)
(package private) static Object	deserializeScalarValue(Common.TypedValue protoElement)
private static boolean	equalRows(Iterable<Object> rows, Iterable<Object> otherRows)
boolean	equals(Object o)
static Meta.Frame	fromProto(Common.Frame proto)
int	hashCode()
(package private) static boolean	isNewStyleColumn(Common.ColumnValue column) Determines whether this message contains the new attributes in the message.
(package private) static Object	parseArray(Common.TypedValue array) Recursively parses a TypedValue while it is an array.
(package private) static Object	parseColumn(Common.ColumnValue column) Parses the value for a ColumnValue using the separated array and scalar attributes.
(package private) static void	parseColumn(Common.Row.Builder rowBuilder, Object column)
(package private) static Object	parseOldStyleColumn(Common.ColumnValue column) For Calcite 1.5, we made the mistake of using array length to determine when the value for a column is a scalar or an array.
(package private) static Common.TypedValue	serializeScalar(Object element)
Common.Frame	toProto()
(package private) static void	validateColumnValue(Common.ColumnValue column) Verifies that a ColumnValue has only a scalar or array value, not both and not neither.

Methods inherited from class java.lang.Object

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

Field Detail

HAS_ARRAY_VALUE_DESCRIPTOR

private static final com.google.protobuf.Descriptors.FieldDescriptor HAS_ARRAY_VALUE_DESCRIPTOR

SCALAR_VALUE_DESCRIPTOR

private static final com.google.protobuf.Descriptors.FieldDescriptor SCALAR_VALUE_DESCRIPTOR

EMPTY

public static final Meta.Frame EMPTY

Frame that has zero rows and is the last frame.

MORE

public static final Meta.Frame MORE

Frame that has zero rows but may have another frame.

offset

public final long offset

Zero-based offset of first row.

done

public final boolean done

Whether this is definitely the last frame of rows. If true, there are no more rows. If false, there may or may not be more rows.

rows

public final Iterable<Object> rows

The rows.

Constructor Detail

Frame

public Frame(long offset,
             boolean done,
             Iterable<Object> rows)

Method Detail

create

public static Meta.Frame create(long offset,
                                boolean done,
                                List<Object> rows)

toProto

public Common.Frame toProto()

parseColumn

static void parseColumn(Common.Row.Builder rowBuilder,
                        Object column)

serializeScalar

static Common.TypedValue serializeScalar(Object element)

fromProto

public static Meta.Frame fromProto(Common.Frame proto)

isNewStyleColumn

static boolean isNewStyleColumn(Common.ColumnValue column)

Determines whether this message contains the new attributes in the message. We can't directly test for the negative because our hasField trick does not work on repeated fields.

Parameters:

column - The protobuf column object

Returns:

True if the message is the new style, false otherwise.

parseOldStyleColumn

static Object parseOldStyleColumn(Common.ColumnValue column)

For Calcite 1.5, we made the mistake of using array length to determine when the value for a column is a scalar or an array. This method performs the old parsing for backwards compatibility.

Parameters:

column - The protobuf ColumnValue object

Returns:

The parsed value for this column

parseColumn

static Object parseColumn(Common.ColumnValue column)

Parses the value for a ColumnValue using the separated array and scalar attributes.

Parameters:

column - The protobuf ColumnValue object

Returns:

The parse value for this column

parseArray

static Object parseArray(Common.TypedValue array)

Recursively parses a TypedValue while it is an array.

validateColumnValue

static void validateColumnValue(Common.ColumnValue column)

Verifies that a ColumnValue has only a scalar or array value, not both and not neither.

Parameters:

column - The protobuf ColumnValue object

Throws:

IllegalArgumentException - When the above condition is not met

deserializeScalarValue

static Object deserializeScalarValue(Common.TypedValue protoElement)

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Overrides:

equals in class Object

equalRows

private static boolean equalRows(Iterable<Object> rows,
                                 Iterable<Object> otherRows)