Re-using database connection in Java

I have following JavaAWS class in Groovy (it is using Java AWS SDK), but now I don't know how to re-use database connection in stage1 and stage2. Basically I'd like to use the same database connection everywhere and now I am not sure what is the way to achieve it.

My ReplicateInstanceStatus and ReplicateMetricStatistics classes are empty for the moment so I haven't pasted it there.

public class JavaAWS {

    Object database = null

    public static void main(String[] args) {
        def obj = new JavaAWS()
        obj.run()
    }
    public JavaAWS() {
        database = new MongoClient()
    }

    public void run() {
        println "Running stage 1 ReplicateInstanceStatus"
        def stage1 = new ReplicateInstanceStatus()
        def ret1 = stage1.run()

        println "Running stage 2 ReplicateMetricStatistics"
        def stage2 = new ReplicateMetricStatistics()
        def ret2 = stage2.run()

    }
}