com.google.cloud.bigtable.hbase.adapters.filters

Class WhileMatchFilterAdapter

java.lang.Object

com.google.cloud.bigtable.hbase.adapters.filters.TypedFilterAdapterBase<org.apache.hadoop.hbase.filter.WhileMatchFilter>

com.google.cloud.bigtable.hbase.adapters.filters.WhileMatchFilterAdapter

All Implemented Interfaces:

TypedFilterAdapter<org.apache.hadoop.hbase.filter.WhileMatchFilter>

@InternalApi(value="For internal usage only")
public class WhileMatchFilterAdapter
extends TypedFilterAdapterBase<org.apache.hadoop.hbase.filter.WhileMatchFilter>

Adapter for WhileMatchFilter.

For internal use only - public for technical reasons.

Constructor Summary

Constructors

Constructor and Description
WhileMatchFilterAdapter(FilterAdapter subFilterAdapter) Constructor for WhileMatchFilterAdapter.

Method Summary

Modifier and Type	Method and Description
com.google.cloud.bigtable.data.v2.models.Filters.Filter	adapt(FilterAdapterContext context, org.apache.hadoop.hbase.filter.WhileMatchFilter filter) Adapt the given filter.
FilterSupportStatus	isFilterSupported(FilterAdapterContext context, org.apache.hadoop.hbase.filter.WhileMatchFilter filter) Determine if the given filter can be adapted to a Bigtable RowFilter.

Methods inherited from class com.google.cloud.bigtable.hbase.adapters.filters.TypedFilterAdapterBase

getIndexScanHint

Methods inherited from class java.lang.Object

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

Constructor Detail

WhileMatchFilterAdapter

public WhileMatchFilterAdapter(FilterAdapter subFilterAdapter)

Constructor for WhileMatchFilterAdapter.

Parameters:

subFilterAdapter - a FilterAdapter object.

Method Detail

adapt

public com.google.cloud.bigtable.data.v2.models.Filters.Filter adapt(FilterAdapterContext context,
                                                                     org.apache.hadoop.hbase.filter.WhileMatchFilter filter)
                                                              throws IOException

Adapt the given filter. Implementers of this method should assume that isFilterSupported has already been called with a result indicating it is in fact supproted.

Adapt WhileMatchFilter as follow:

| V +--------+--------+ | | | | label('id-in') wrappedFilter.filter() | | | | sink() +-----+-----+ + | | label('id-out') all() | | sink() | + v

The above implementation gives enough information from the server side to determine whether the remaining rows should be filtered out. For each WhileMatchFilter instance, an unique ID is generated for labeling. The input label is the unique ID suffixed by "-in" and the output label is the unique ID suffixed by "-out". When wrappedFilter decides to filter out the rest of rows, there is no out label ("id-out") applied in the output. In other words, when there is a missing "id-out" for an input "id-in", WhileMatchFilter.filterAllRemaining() returns true. Since the server continues to send result even though WhileMatchFilter.filterAllRemaining() returns true, we need to replace this WhileMatchFilter instance with a "block all" filter and rescan from the next row.

Parameters:

context - a FilterAdapterContext object.

filter - a S object.

Returns:

a Filters.Filter object.

Throws:

IOException - if any.

isFilterSupported

public FilterSupportStatus isFilterSupported(FilterAdapterContext context,
                                             org.apache.hadoop.hbase.filter.WhileMatchFilter filter)

Determine if the given filter can be adapted to a Bigtable RowFilter.

Parameters:

context - a FilterAdapterContext object.

filter - a S object.

Returns:

a FilterSupportStatus object.