use of org.apache.hadoop.hbase.protobuf.generated.AggregateProtos.AggregateService in project hbase by apache.
the class AggregationClient method max.
/**
* It gives the maximum value of a column for a given column family for the
* given range. In case qualifier is null, a max of all values for the given
* family is returned.
* @param table
* @param ci
* @param scan
* @return max val <>
* @throws Throwable
* The caller is supposed to handle the exception as they are thrown
* & propagated to it.
*/
public <R, S, P extends Message, Q extends Message, T extends Message> R max(final Table table, final ColumnInterpreter<R, S, P, Q, T> ci, final Scan scan) throws Throwable {
final AggregateRequest requestArg = validateArgAndGetPB(scan, ci, false);
class MaxCallBack implements Batch.Callback<R> {
R max = null;
R getMax() {
return max;
}
@Override
public synchronized void update(byte[] region, byte[] row, R result) {
max = (max == null || (result != null && ci.compare(max, result) < 0)) ? result : max;
}
}
MaxCallBack aMaxCallBack = new MaxCallBack();
table.coprocessorService(AggregateService.class, scan.getStartRow(), scan.getStopRow(), new Batch.Call<AggregateService, R>() {
@Override
public R call(AggregateService instance) throws IOException {
RpcController controller = new AggregationClientRpcController();
CoprocessorRpcUtils.BlockingRpcCallback<AggregateResponse> rpcCallback = new CoprocessorRpcUtils.BlockingRpcCallback<>();
instance.getMax(controller, requestArg, rpcCallback);
AggregateResponse response = rpcCallback.get();
if (controller.failed()) {
throw new IOException(controller.errorText());
}
if (response.getFirstPartCount() > 0) {
ByteString b = response.getFirstPart(0);
Q q = getParsedGenericInstance(ci.getClass(), 3, b);
return ci.getCellValueFromProto(q);
}
return null;
}
}, aMaxCallBack);
return aMaxCallBack.getMax();
}
use of org.apache.hadoop.hbase.protobuf.generated.AggregateProtos.AggregateService in project hbase by apache.
the class AggregationClient method getMedianArgs.
/**
* It helps locate the region with median for a given column whose weight
* is specified in an optional column.
* From individual regions, it obtains sum of values and sum of weights.
* @param table
* @param ci
* @param scan
* @return pair whose first element is a map between start row of the region
* and (sum of values, sum of weights) for the region, the second element is
* (sum of values, sum of weights) for all the regions chosen
* @throws Throwable
*/
private <R, S, P extends Message, Q extends Message, T extends Message> Pair<NavigableMap<byte[], List<S>>, List<S>> getMedianArgs(final Table table, final ColumnInterpreter<R, S, P, Q, T> ci, final Scan scan) throws Throwable {
final AggregateRequest requestArg = validateArgAndGetPB(scan, ci, false);
final NavigableMap<byte[], List<S>> map = new TreeMap<>(Bytes.BYTES_COMPARATOR);
class StdCallback implements Batch.Callback<List<S>> {
S sumVal = null, sumWeights = null;
public synchronized Pair<NavigableMap<byte[], List<S>>, List<S>> getMedianParams() {
List<S> l = new ArrayList<>(2);
l.add(sumVal);
l.add(sumWeights);
Pair<NavigableMap<byte[], List<S>>, List<S>> p = new Pair<>(map, l);
return p;
}
@Override
public synchronized void update(byte[] region, byte[] row, List<S> result) {
map.put(row, result);
sumVal = ci.add(sumVal, result.get(0));
sumWeights = ci.add(sumWeights, result.get(1));
}
}
StdCallback stdCallback = new StdCallback();
table.coprocessorService(AggregateService.class, scan.getStartRow(), scan.getStopRow(), new Batch.Call<AggregateService, List<S>>() {
@Override
public List<S> call(AggregateService instance) throws IOException {
RpcController controller = new AggregationClientRpcController();
CoprocessorRpcUtils.BlockingRpcCallback<AggregateResponse> rpcCallback = new CoprocessorRpcUtils.BlockingRpcCallback<>();
instance.getMedian(controller, requestArg, rpcCallback);
AggregateResponse response = rpcCallback.get();
if (controller.failed()) {
throw new IOException(controller.errorText());
}
List<S> list = new ArrayList<>();
for (int i = 0; i < response.getFirstPartCount(); i++) {
ByteString b = response.getFirstPart(i);
T t = getParsedGenericInstance(ci.getClass(), 4, b);
S s = ci.getPromotedValueFromProto(t);
list.add(s);
}
return list;
}
}, stdCallback);
return stdCallback.getMedianParams();
}
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