@Test
    public void testContainsPoint() {
        RPCAnalysisListener listener = new RPCAnalysisListener(
            new MockReceiver(),
            CONFIG,
            CACHE,
            NAMING_CONTROL
        );
        Assertions.assertTrue(listener.containsPoint(AnalysisListener.Point.Entry));
        Assertions.assertTrue(listener.containsPoint(AnalysisListener.Point.Local));
        Assertions.assertTrue(listener.containsPoint(AnalysisListener.Point.Exit));
        Assertions.assertFalse(listener.containsPoint(AnalysisListener.Point.First));
        Assertions.assertFalse(listener.containsPoint(AnalysisListener.Point.Segment));
    }
RPCAnalysisListenerTest includes the most segment to source(s) logic. This test covers most cases about the segment
to sources translation.

This test is a good way to study about how OAP analysis trace segment.
oap-server/server-receiver-plugin/skywalking-trace-receiver-plugin/src/test/java/org/apache/skywalking/oap/server/receiver/trace/provider/parser/listener/RPCAnalysisListenerTest.java