Data-Flow Management in Streaming Analysis - Real-Time Analytics - page 125

public class RedisSource extends AbstractSource
implements Configurable, EventDrivenSource {
The Configurable interface has a single configure method, which is used to
obtain the Redis hostname, port, and subscription channel. In this case, all
of the configuration parameters have defaults:
String redisHost;
int redisPort;
String redisChannel;
Jedis jedis;
public void configure(Context context) {
redisHost = context.getString("redis-host",
"localhost");
redisPort = context.getInteger("redis-port",
6379);
redisChannel = context.getString("redis-channel",
"flume");
}
The EventDrivenSource does not actually require any methods be
implemented; it is only used to determine the type of source. Any threads
or even handlers are set up and broken down and are handled in the start
and stop methods. In this case, most of the work is done in the start
method:
@Override
public synchronized void start() {
super .start();
processor = getChannelProcessor();
First, the ChannelProcessor is obtained for future use. Recall that the
ChannelProcessor decides which Channel will be used based on the
Event . The ChannelProcessor is used by the subscription thread that is
established next:
JedisPool pool = new JedisPool(
new JedisPoolConfig(),redisHost,redisPort);
jedis = pool.getResource();