org.apache.flink.table.runtime.operators.rank

Class ComparableRecordComparator

java.lang.Object

org.apache.flink.table.runtime.operators.rank.ComparableRecordComparator

All Implemented Interfaces:

Serializable, Comparator<RowData>, RecordComparator

public final class ComparableRecordComparator
extends Object
implements RecordComparator

Because it's impossible to restore a RecordComparator instance generated by GeneratedRecordComparator from checkpoint snapshot. Hence, we introduce ComparableRecordComparator class to wrap the GeneratedRecordComparator. A ComparableRecordComparator instance is serializable and can restore the RecordComparator from the serialized ComparableRecordComparator. Besides, the equals(Object) doesn't take GeneratedRecordComparator into account, because the code is not deterministic across different client. Therefore, equals(Object) only compares the meta information used for generating code of RecordComparator.

Note: currently, this class is only used for RetractableTopNFunction.

See Also:

RetractableTopNFunction, Serialized Form

Constructor Summary

Constructors

Constructor and Description
ComparableRecordComparator(GeneratedRecordComparator generatedRecordComparator, int[] compareKeyPositions, LogicalType[] compareKeyTypes, boolean[] compareOrders, boolean[] nullsIsLast)

Method Summary

Modifier and Type	Method and Description
int	compare(RowData o1, RowData o2)
boolean	equals(Object o)
GeneratedRecordComparator	getGeneratedRecordComparator()
int	hashCode()

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Comparator

comparing, comparing, comparingDouble, comparingInt, comparingLong, naturalOrder, nullsFirst, nullsLast, reversed, reverseOrder, thenComparing, thenComparing, thenComparing, thenComparingDouble, thenComparingInt, thenComparingLong

Constructor Detail

ComparableRecordComparator

public ComparableRecordComparator(GeneratedRecordComparator generatedRecordComparator,
                                  int[] compareKeyPositions,
                                  LogicalType[] compareKeyTypes,
                                  boolean[] compareOrders,
                                  boolean[] nullsIsLast)

Method Detail

getGeneratedRecordComparator

public GeneratedRecordComparator getGeneratedRecordComparator()

compare

public int compare(RowData o1,
                   RowData o2)

Specified by:

compare in interface Comparator<RowData>

Specified by:

compare in interface RecordComparator

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object o)

Specified by:

equals in interface Comparator<RowData>

Overrides:

equals in class Object