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Re: problem in testing coprocessor endpoint
You can't register and end point just for one table. It's like a stored
procedure - you choose to run it and pass parameters to it.

On Friday, July 12, 2013, ch huang wrote:

> what your describe is how to load endpoint coprocessor for every region in
> the hbase, what i want to do is just load it into my test table ,only for
> the regions of the table
>
> On Fri, Jul 12, 2013 at 12:07 PM, Asaf Mesika <[EMAIL PROTECTED]>
> wrote:
>
> > The only way to register endpoint coprocessor jars is by placing them in
> > lib dir if hbase and modifying hbase-site.xml to point to it under a
> > property name I forgot at the moment.
> > What you described is a way to register an Observer type coprocessor.
> >
> >
> > On Friday, July 12, 2013, ch huang wrote:
> >
> > > i am testing coprocessor endpoint function, here is my testing process
> > ,and
> > > error i get ,hope any expert on coprocessor can help me out
> > >
> > >
> > > # vi ColumnAggregationProtocol.java
> > >
> > > import java.io.IOException;
> > > import org.apache.hadoop.hbase.ipc.CoprocessorProtocol;
> > > // A sample protocol for performing aggregation at regions.
> > > public interface ColumnAggregationProtocol
> > > extends CoprocessorProtocol {
> > > // Perform aggregation for a given column at the region. The
> aggregation
> > > // will include all the rows inside the region. It can be extended to
> > > // allow passing start and end rows for a fine-grained aggregation.
> > >    public long sum(byte[] family, byte[] qualifier) throws IOException;
> > > }
> > >
> > >
> > > # vi ColumnAggregationEndpoint.java
> > >
> > >
> > > import java.io.FileWriter;
> > > import java.io.IOException;
> > > import java.util.ArrayList;
> > > import java.util.List;
> > > import org.apache.hadoop.hbase.CoprocessorEnvironment;
> > > import org.apache.hadoop.hbase.KeyValue;
> > > import org.apache.hadoop.hbase.client.Scan;
> > > import org.apache.hadoop.hbase.coprocessor.BaseEndpointCoprocessor;
> > > import
> org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment;
> > > import org.apache.hadoop.hbase.ipc.ProtocolSignature;
> > > import org.apache.hadoop.hbase.regionserver.HRegion;
> > > import org.apache.hadoop.hbase.regionserver.InternalScanner;
> > > import org.apache.hadoop.hbase.util.Bytes;
> > >
> > > //Aggregation implementation at a region.
> > >
> > > public class ColumnAggregationEndpoint extends BaseEndpointCoprocessor
> > >   implements ColumnAggregationProtocol {
> > >      @Override
> > >      public long sum(byte[] family, byte[] qualifier)
> > >      throws IOException {
> > >        // aggregate at each region
> > >          Scan scan = new Scan();
> > >          scan.addColumn(family, qualifier);
> > >          long sumResult = 0;
> > >
> > >          CoprocessorEnvironment ce = getEnvironment();
> > >          HRegion hr = ((RegionCoprocessorEnvironment)ce).getRegion();
> > >          InternalScanner scanner = hr.getScanner(scan);
> > >
> > >          try {
> > >            List<KeyValue> curVals = new ArrayList<KeyValue>();
> > >            boolean hasMore = false;
> > >            do {
> > >          curVals.clear();
> > >          hasMore = scanner.next(curVals);
> > >          KeyValue kv = curVals.get(0);
> > >          sumResult += Long.parseLong(Bytes.toString(kv.getValue()));
> > >
> > >            } while (hasMore);
> > >          } finally {
> > >              scanner.close();
> > >          }
> > >          return sumResult;
> > >       }
> > >
> > >       @Override
> > >       public long getProtocolVersion(String protocol, long
> clientVersion)
> > >              throws IOException {
> > >          // TODO Auto-generated method stub
> > >          return 0;
> > >       }
> > >
> > > > 192.168.10.22:9000/alex/test.jar|ColumnAggregationEndpoint|1001<
> http://192.168.10.22:9000/alex/test.jar%7CColumnAggregationEndpoint%7C1001
> >
> > '
> > >
> > > here is my testing java code
> > >
> > > package com.testme.demo;
> > > import java.io.IOException;
>