gemfire-core/src/main/java/com/gemstone/gemfire/internal/redis/executor/hash/HGetExecutor.java

package com.gemstone.gemfire.internal.redis.executor.hash;

import java.util.List;

import com.gemstone.gemfire.cache.Region;
import com.gemstone.gemfire.internal.redis.ByteArrayWrapper;
import com.gemstone.gemfire.internal.redis.Command;
import com.gemstone.gemfire.internal.redis.ExecutionHandlerContext;
import com.gemstone.gemfire.internal.redis.RedisDataType;
import com.gemstone.gemfire.internal.redis.Coder;
import com.gemstone.gemfire.internal.redis.RedisConstants.ArityDef;

public class HGetExecutor extends HashExecutor {

  @Override
  public void executeCommand(Command command, ExecutionHandlerContext context) {
    List<byte[]> commandElems = command.getProcessedCommand();

    if (commandElems.size() < 3) {
      command.setResponse(Coder.getErrorResponse(context.getByteBufAllocator(), ArityDef.HGET));
      return;
    }

    ByteArrayWrapper key = command.getKey();

    checkDataType(key, RedisDataType.REDIS_HASH, context);
    Region<ByteArrayWrapper, ByteArrayWrapper> keyRegion = getRegion(context, key);

    if (keyRegion == null) {
      command.setResponse(Coder.getNilResponse(context.getByteBufAllocator()));
      return;
    }

    byte[] byteField = commandElems.get(FIELD_INDEX);
    ByteArrayWrapper field = new ByteArrayWrapper(byteField);

    ByteArrayWrapper valueWrapper = keyRegion.get(field);

    if (valueWrapper != null) {
      command.setResponse(Coder.getBulkStringResponse(context.getByteBufAllocator(), valueWrapper.toBytes()));
    } else
      command.setResponse(Coder.getNilResponse(context.getByteBufAllocator()));

  }

}