gistfile1.java

import com.google.common.util.concurrent.*;
import org.apache.commons.dbcp.cpdsadapter.DriverAdapterCPDS;
import org.apache.commons.dbcp.datasources.SharedPoolDataSource;
import org.apache.commons.dbutils.AsyncQueryRunner;
import org.apache.commons.dbutils.ResultSetHandler;

import javax.sql.DataSource;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.concurrent.ThreadPoolExecutor;

import static com.google.common.base.Throwables.propagate;
import static com.google.common.util.concurrent.Futures.addCallback;
import static com.google.common.util.concurrent.MoreExecutors.getExitingExecutorService;
import static com.google.common.util.concurrent.MoreExecutors.listeningDecorator;
import static java.util.concurrent.Executors.newCachedThreadPool;

public class AsyncDB {

  public static void main(String[] args) {

    try {

      final DriverAdapterCPDS adapter = new DriverAdapterCPDS();
      adapter.setDriver("org.hsqldb.jdbc.JDBCDriver");
      adapter.setUrl("jdbc:hsqldb:mem:mymemdb");
      adapter.setUser("SA");
      adapter.setPassword(null);

      final SharedPoolDataSource datasource = new SharedPoolDataSource();
      datasource.setConnectionPoolDataSource(adapter);
      datasource.setMaxActive(10);
      datasource.setMaxWait(50);

      datasource.getConnection().createStatement().execute("create table users(name varchar(256))");

      final ListeningExecutorService executor =
        listeningDecorator(
          getExitingExecutorService(
            (ThreadPoolExecutor) newCachedThreadPool()));

      final AsyncQueryRunner runner = new AsyncQueryRunner(datasource, executor);

      final ListenableFuture<Integer> future =
        (ListenableFuture<Integer>) runner.query(
          "select count(*) from users",
          new ResultSetHandler<Integer>() {
            @Override
            public Integer handle(ResultSet resultSet) throws SQLException {
              while (resultSet.next()) {
                return resultSet.getInt(1);
              }
              return 0;
            }
          });

      addCallback(future, new FutureCallback<Integer>() {

        @Override
        public void onSuccess(Integer userCount) {
          System.out.println("There are " + userCount + " users");
        }

        @Override
        public void onFailure(Throwable throwable) {
          propagate(throwable);
        }

      });

    } catch (Throwable e) {
      propagate(e);
    }
  }

}