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# Geode Continuous Query Example

This is a simple example that demonstrates Apache Geode's Continuous Queries(CQs) feature.  CQs allow clients to subscribe
to server-side events using a SQL-like query.  When a client registers a CQ, the client will receive all events that
modify the query results.

In this example, the client program will first register a CQ with the query 
`SELECT * FROM /example-region i where i > 70`. The region has keys and values that are both Integer types.
 
The program loops, randomly generating two integers to put on the server as the key and value.
 
If a value is either created or updated that is greater than 70, the above CQ will trigger the `RandomEventLister`,
which prints to stdout.

The client will generate data for 20 seconds, close the CQ and Cache, and then exit.

This example assumes you have installed Java and Geode.

## Steps

1. From the `geode-examples/cq` directory, build the example.

        $ ../gradlew build

2. Next start a locator, start a server, and create a region.

        $ gfsh run --file=scripts/start.gfsh

3. Run the example to demonstrate continues queries.

        $ ../gradlew run

4. Shut down the server.

        $ gfsh run --file=scripts/stop.gfsh