Elasticsearch 2.3.4 plugin test error

[8a98bb2968a03fe24acf]

hi there
i developed elasticseach 2.3.4 plugin
i want to run my elasticsearch plugin unit test code
i build it with gradle

because of an error, i edited my code simply
this is my simple test code

public class ClusterHealthMetricCollectorTest extends ESSingleNodeTestCase {
    public void testClusterHealthMetricCollect() {
        assertEquals("a", "a");
    }
}

and this is an test message

com.naver.paas.es.monitoring.collect.cluster.ClusterHealthMetricCollectorTest STANDARD_ERROR
    10월 11, 2017 6:25:50 오후 org.elasticsearch.bootstrap.JNANatives tryMlockall
    warning: Unable to lock JVM Memory: error=78,reason=Function not implemented
    10월 11, 2017 6:25:50 오후 org.elasticsearch.bootstrap.JNANatives tryMlockall
    warning: This can result in part of the JVM being swapped out.
    Oct 11, 2017 10:25:55 PM org.elasticsearch.node.Node <init>
    INFO: [node_s_0] version[2.3.4], pid[73173], build[e455fd0/2016-06-30T11:24:31Z]
    Oct 11, 2017 10:25:55 PM org.elasticsearch.node.Node <init>
    INFO: [node_s_0] initializing ...
    Oct 11, 2017 10:25:55 PM org.elasticsearch.plugins.PluginsService <init>
    INFO: [node_s_0] modules [], plugins [], sites []
    Oct 11, 2017 10:25:55 PM org.elasticsearch.env.NodeEnvironment maybeLogPathDetails
    INFO: [node_s_0] using [1] data paths, mounts [[/ (/dev/disk1)]], net usable_space [178.4gb], net total_space [232.5gb], spins? [unknown], types [hfs]
    Oct 11, 2017 10:25:55 PM org.elasticsearch.env.NodeEnvironment maybeLogHeapDetails
    INFO: [node_s_0] heap size [3.5gb], compressed ordinary object pointers [true]
    Oct 11, 2017 10:25:55 PM org.elasticsearch.env.NodeEnvironment maybeWarnFileDescriptors
    WARNING: [node_s_0] max file descriptors [10240] for elasticsearch process likely too low, consider increasing to at least [65536]
    Oct 11, 2017 10:25:58 PM org.elasticsearch.node.Node <init>
    INFO: [node_s_0] initialized
    Oct 11, 2017 10:25:58 PM org.elasticsearch.node.Node start
    INFO: [node_s_0] starting ...
    Oct 11, 2017 10:25:58 PM org.elasticsearch.transport.TransportService doStart
    INFO: [node_s_0] publish_address {local[1]}, bound_addresses {local[1]}
    Oct 11, 2017 10:25:58 PM org.elasticsearch.discovery.DiscoveryService doStart
    INFO: [node_s_0] single-node-cluster-CHILD_VM=[0]-CLUSTER_SEED=[-7497988778183746746]-HASH=[11BA0F90098E5]/k3aLPoXVRX-TwTBwD3TonA
    Oct 11, 2017 10:25:58 PM org.elasticsearch.cluster.service.InternalClusterService runTasksForExecutor
    INFO: [node_s_0] new_master {node_s_0}{k3aLPoXVRX-TwTBwD3TonA}{local}{local[1]}{local=true}, reason: local-disco-initial_connect(master)
    Oct 11, 2017 10:25:58 PM org.elasticsearch.node.Node start
    INFO: [node_s_0] started
    Oct 11, 2017 10:25:58 PM org.elasticsearch.gateway.GatewayService$GatewayRecoveryListener$1 clusterStateProcessed
    INFO: [node_s_0] recovered [0] indices into cluster_state

com.naver.paas.es.monitoring.collect.cluster.ClusterHealthMetricCollectorTest STANDARD_ERROR
    Oct 11, 2017 10:25:58 PM org.elasticsearch.test.ESSingleNodeTestCase tearDown
    INFO: [ClusterHealthMetricCollectorTest#testClusterHealthMetricCollect]: cleaning up after test
    Oct 11, 2017 10:25:58 PM org.elasticsearch.node.Node stop
    INFO: [node_s_0] stopping ...
    Oct 11, 2017 10:25:58 PM org.elasticsearch.node.Node stop
    INFO: [node_s_0] stopped
    Oct 11, 2017 10:25:58 PM org.elasticsearch.node.Node close
    INFO: [node_s_0] closing ...
    Oct 11, 2017 10:25:58 PM org.elasticsearch.node.Node close
    INFO: [node_s_0] closed
    NOTE: test params are: codec=Asserting(Lucene54): {}, docValues:{}, sim=RandomSimilarity(queryNorm=false,coord=crazy): {}, locale=en-SG, timezone=Pacific/Enderbury

    NOTE: Mac OS X 10.12.6 x86_64/Oracle Corporation 1.8.0_144 (64-bit)/cpus=4,threads=1,free=108011696,total=218103808

    NOTE: All tests run in this JVM: [ClusterHealthMetricCollectorTest]

> Building 85% > :test

Build stoped on 85%
i used this command gradle test

please help me