@InterfaceAudience.Public public class SkipFilter extends org.apache.hadoop.hbase.filter.FilterBase
For example, if all columns in a row represent weights of different things,
with the values being the actual weights, and we want to filter out the
entire row if any of its weights are zero. In this case, we want to prevent
rows from being emitted if a single key is filtered. Combine this filter
with a ValueFilter
:
scan.setFilter(new SkipFilter(new ValueFilter(CompareOp.NOT_EQUAL,
new BinaryComparator(Bytes.toBytes(0))));
Any row which contained a column whose value was 0 will be filtered out
(since ValueFilter will not pass that Cell).
Without this filter, the other non-zero valued columns in the row would still
be emitted.
Filter.ReturnCode
Constructor and Description |
---|
SkipFilter(Filter filter) |
Modifier and Type | Method and Description |
---|---|
boolean |
equals(Object obj) |
Filter.ReturnCode |
filterCell(Cell c)
A way to filter based on the column family, column qualifier and/or the column value.
|
Filter.ReturnCode |
filterKeyValue(Cell c)
Deprecated.
|
boolean |
filterRow()
Filters that never filter by rows based on previously gathered state from
Filter.filterCell(Cell) can inherit this implementation that
never filters a row. |
boolean |
filterRowKey(Cell cell)
Filters a row based on the row key.
|
Filter |
getFilter() |
boolean |
hasFilterRow()
Fitlers that never filter by modifying the returned List of Cells can
inherit this implementation that does nothing.
|
int |
hashCode() |
boolean |
isFamilyEssential(byte[] name)
By default, we require all scan's column families to be present.
|
static SkipFilter |
parseFrom(byte[] pbBytes) |
void |
reset()
Filters that are purely stateless and do nothing in their reset() methods can inherit
this null/empty implementation.
|
byte[] |
toByteArray()
Return length 0 byte array for Filters that don't require special serialization
|
String |
toString()
Return filter's info for debugging and logging purpose.
|
Cell |
transformCell(Cell v)
By default no transformation takes place
Give the filter a chance to transform the passed KeyValue.
|
createFilterFromArguments, filterAllRemaining, filterRowCells, filterRowKey, getNextCellHint
isReversed, setReversed
public SkipFilter(Filter filter)
public void reset() throws IOException
org.apache.hadoop.hbase.filter.FilterBase
IOException
.reset
in class org.apache.hadoop.hbase.filter.FilterBase
IOException
- in case an I/O or an filter specific failure needs to be signaled.public boolean filterRowKey(Cell cell) throws IOException
Filter
Filter.filterCell(Cell)
below.
If Filter.filterAllRemaining()
returns true, then Filter.filterRowKey(Cell)
should
also return true.
Concrete implementers can signal a failure condition in their code by throwing an
IOException
.filterRowKey
in class org.apache.hadoop.hbase.filter.FilterBase
cell
- The first cell coming in the new rowIOException
- in case an I/O or an filter specific failure needs to be signaled.@Deprecated public Filter.ReturnCode filterKeyValue(Cell c) throws IOException
Filter
ReturnCode.NEXT_ROW
, it should return
ReturnCode.NEXT_ROW
until Filter.reset()
is called just in case the caller calls
for the next row.
Concrete implementers can signal a failure condition in their code by throwing an
IOException
.filterKeyValue
in class Filter
c
- the Cell in questionIOException
- in case an I/O or an filter specific failure needs to be signaled.Filter.ReturnCode
public Filter.ReturnCode filterCell(Cell c) throws IOException
Filter
ReturnCode.NEXT_ROW
, it should return
ReturnCode.NEXT_ROW
until Filter.reset()
is called just in case the caller calls
for the next row.
Concrete implementers can signal a failure condition in their code by throwing an
IOException
.filterCell
in class Filter
c
- the Cell in questionIOException
- in case an I/O or an filter specific failure needs to be signaled.Filter.ReturnCode
public Cell transformCell(Cell v) throws IOException
org.apache.hadoop.hbase.filter.FilterBase
transformCell
in class org.apache.hadoop.hbase.filter.FilterBase
v
- the KeyValue in questionIOException
- in case an I/O or an filter specific failure needs to be signaled.The transformed KeyValue is what is eventually returned to the client. Most filters will
return the passed KeyValue unchanged.
,
for an example of a
transformation.
Concrete implementers can signal a failure condition in their code by throwing an
{@link IOException}.
public boolean filterRow()
org.apache.hadoop.hbase.filter.FilterBase
Filter.filterCell(Cell)
can inherit this implementation that
never filters a row.
Last chance to veto row based on previous Filter.filterCell(Cell)
calls. The filter
needs to retain state then return a particular value for this call if they wish to exclude a
row if a certain column is missing (for example).
Concrete implementers can signal a failure condition in their code by throwing an
IOException
.filterRow
in class org.apache.hadoop.hbase.filter.FilterBase
public boolean hasFilterRow()
org.apache.hadoop.hbase.filter.FilterBase
hasFilterRow
in class org.apache.hadoop.hbase.filter.FilterBase
public byte[] toByteArray() throws IOException
org.apache.hadoop.hbase.filter.FilterBase
toByteArray
in class org.apache.hadoop.hbase.filter.FilterBase
IOException
- in case an I/O or an filter specific failure needs to be signaled.public static SkipFilter parseFrom(byte[] pbBytes) throws org.apache.hadoop.hbase.exceptions.DeserializationException
pbBytes
- A pb serialized SkipFilter
instanceSkipFilter
made from bytes
org.apache.hadoop.hbase.exceptions.DeserializationException
toByteArray()
public boolean isFamilyEssential(byte[] name) throws IOException
org.apache.hadoop.hbase.filter.FilterBase
IOException
.isFamilyEssential
in class org.apache.hadoop.hbase.filter.FilterBase
IOException
- in case an I/O or an filter specific failure needs to be signaled.public String toString()
org.apache.hadoop.hbase.filter.FilterBase
toString
in class org.apache.hadoop.hbase.filter.FilterBase
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