Why is JanusGraph saying its dropping all the Vertexes when its looking like its really not?
logger.info("g.V().count().next():\t" + g.V().count().next());
g.V().drop().iterate();
logger.info("g.V().count().next():\t" + g.V().count().next());
I run code to drop Vertexes and JanusGraph's response seems to indicate the server's done so.
JanusGraph and Gremlin-Servers are supposed to handle transactions automatically.
But when I run the same drop code again => Bam! 70005 Vertexes to drop again!
If you start JanusGraph as a server (called JanusGraph Server) then it's Gremlin Server with some additions for JanusGraph and Gremlin Server handles transactions automatically: tinkerpop.apache.org/docs/current/reference/… I don't know about OrientDB though. – Florian Hockmann
2023-05-10 08:56:00,444 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 08:56:00,539 [INFO] [c.d.o.d.i.c.DefaultMavenCoordinates.main] :: DataStax Java driver for Apache Cassandra(R) (com.datastax.oss:java-driver-core) version 4.15.0
2023-05-10 08:56:01,067 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] :: Using native clock for microsecond precision
2023-05-10 08:56:01,344 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] :: [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/127.0.0.1:9042, hostId=null, hashCode=22ef1fc3)=null; please provide the correct local DC, or check your contact points
2023-05-10 08:56:01,595 [INFO] [o.j.g.i.UniqueInstanceIdRetriever.main] :: Generated unique-instance-id=c0a8563c2808-rmt-lap-win201
2023-05-10 08:56:01,617 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 08:56:01,656 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] :: Using native clock for microsecond precision
2023-05-10 08:56:01,701 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] :: [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/[0:0:0:0:0:0:0:1]:9042, hostId=null, hashCode=411a6f76)=null; please provide the correct local DC, or check your contact points
2023-05-10 08:56:01,716 [INFO] [o.j.d.c.ExecutorServiceBuilder.main] :: Initiated fixed thread pool of size 40
2023-05-10 08:56:01,836 [INFO] [o.j.g.d.StandardJanusGraph.main] :: Gremlin script evaluation is disabled
2023-05-10 08:56:01,864 [INFO] [o.j.d.l.k.KCVSLog.main] :: Loaded unidentified ReadMarker start time 2023-05-10T13:56:01.864177Z into org.janusgraph.diskstorage.log.kcvs.KCVSLog$MessagePuller@f1d0004
2023-05-10 08:56:01,923 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 08:56:03,469 [INFO] [Main.main] :: g.V().count().next(): 70005
2023-05-10 08:56:03,473 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 08:59:05,959 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 08:59:07,381 [INFO] [Main.main] :: g.V().count().next(): 0
2023-05-10 09:00:57,848 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 09:00:57,955 [INFO] [c.d.o.d.i.c.DefaultMavenCoordinates.main] :: DataStax Java driver for Apache Cassandra(R) (com.datastax.oss:java-driver-core) version 4.15.0
2023-05-10 09:00:58,489 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] :: Using native clock for microsecond precision
2023-05-10 09:00:58,758 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] :: [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/[0:0:0:0:0:0:0:1]:9042, hostId=null, hashCode=70036733)=null; please provide the correct local DC, or check your contact points
2023-05-10 09:00:58,995 [INFO] [o.j.g.i.UniqueInstanceIdRetriever.main] :: Generated unique-instance-id=c0a8563c12580-rmt-lap-win201
2023-05-10 09:00:59,018 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 09:00:59,112 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] :: Using native clock for microsecond precision
2023-05-10 09:00:59,183 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] :: [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/[0:0:0:0:0:0:0:1]:9042, hostId=null, hashCode=411a6f76)=null; please provide the correct local DC, or check your contact points
2023-05-10 09:00:59,207 [INFO] [o.j.d.c.ExecutorServiceBuilder.main] :: Initiated fixed thread pool of size 40
2023-05-10 09:00:59,334 [INFO] [o.j.g.d.StandardJanusGraph.main] :: Gremlin script evaluation is disabled
2023-05-10 09:00:59,358 [INFO] [o.j.d.l.k.KCVSLog.main] :: Loaded unidentified ReadMarker start time 2023-05-10T14:00:59.358381Z into org.janusgraph.diskstorage.log.kcvs.KCVSLog$MessagePuller@f1d0004
2023-05-10 09:00:59,413 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 09:01:00,946 [INFO] [Main.main] :: g.V().count().next(): 70005
2023-05-10 09:01:00,951 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
Variations include combinations of: janusGraph.openManagement() + janusGraphManagement.commit(), g.V().drop(), g.tx().commit(), and janusGraph.tx().commit().
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
import org.janusgraph.core.JanusGraph;
import org.janusgraph.core.JanusGraphFactory;
import org.janusgraph.core.JanusGraphVertex;
public class Test5 {
private static final Logger logger = LogManager.getLogger(Main.class);
public static void main(String[] args) {
JanusGraph janusGraph = JanusGraphFactory.build().set("storage.backend", "cql").set("storage.hostname", "localhost:9042").open();
GraphTraversalSource g = janusGraph.traversal();
logger.info("g.V().count().next():\t" + g.V().count().next());
g.V().drop().iterate();
logger.info("g.V().count().next():\t" + g.V().count().next());
JanusGraphVertex janusGraphVertex = janusGraph.addVertex();
janusGraph.close();
}
}
Thanks Stephen Mallette!
This does put in the same bind I was trying to workaround, but since (I don't think) I'm not using JanusGraph-Server like "inmemory", I'll need to face why the commit() seems to breakdown.
2023-05-10 08:08:14,037 [INFO] [Main.main] :: vp[empty]
2023-05-10 08:08:14,039 [INFO] [Main.main] :: vp[empty]
2023-05-10 08:10:42,407 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 08:10:42,486 [INFO] [c.d.o.d.i.c.DefaultMavenCoordinates.main] :: DataStax Java driver for Apache Cassandra(R) (com.datastax.oss:java-driver-core) version 4.15.0
2023-05-10 08:10:46,473 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 08:10:46,556 [INFO] [c.d.o.d.i.c.DefaultMavenCoordinates.main] :: DataStax Java driver for Apache Cassandra(R) (com.datastax.oss:java-driver-core) version 4.15.0
2023-05-10 08:10:47,045 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] :: Using native clock for microsecond precision
2023-05-10 08:10:47,296 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] :: [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/[0:0:0:0:0:0:0:1]:9042, hostId=null, hashCode=ca3ba3b)=null; please provide the correct local DC, or check your contact points
2023-05-10 08:10:47,521 [INFO] [o.j.g.i.UniqueInstanceIdRetriever.main] :: Generated unique-instance-id=c0a8563c6312-rmt-lap-win201
2023-05-10 08:10:47,536 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 08:10:47,562 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] :: Using native clock for microsecond precision
2023-05-10 08:10:47,599 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] :: [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/[0:0:0:0:0:0:0:1]:9042, hostId=null, hashCode=51018eef)=null; please provide the correct local DC, or check your contact points
2023-05-10 08:10:47,616 [INFO] [o.j.d.c.ExecutorServiceBuilder.main] :: Initiated fixed thread pool of size 40
2023-05-10 08:10:47,735 [INFO] [o.j.g.d.StandardJanusGraph.main] :: Gremlin script evaluation is disabled
2023-05-10 08:10:47,759 [INFO] [o.j.d.l.k.KCVSLog.main] :: Loaded unidentified ReadMarker start time 2023-05-10T13:10:47.759892Z into org.janusgraph.diskstorage.log.kcvs.KCVSLog$MessagePuller@f1d0004
2023-05-10 08:10:47,813 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 08:10:49,268 [INFO] [Main.main] :: g.V().count().next(): 70005
2023-05-10 08:10:49,271 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 08:18:47,042 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 08:18:47,156 [INFO] [c.d.o.d.i.c.DefaultMavenCoordinates.main] :: DataStax Java driver for Apache Cassandra(R) (com.datastax.oss:java-driver-core) version 4.15.0
2023-05-10 08:18:47,679 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] :: Using native clock for microsecond precision
2023-05-10 08:18:48,020 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] :: [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/127.0.0.1:9042, hostId=null, hashCode=5fc0cf)=null; please provide the correct local DC, or check your contact points
2023-05-10 08:18:48,340 [INFO] [o.j.g.i.UniqueInstanceIdRetriever.main] :: Generated unique-instance-id=c0a8563c13272-rmt-lap-win201
2023-05-10 08:18:48,363 [INFO] [c.d.o.d.i.c.ContactPoints.main] :: Contact point localhost:9042 resolves to multiple addresses, will use them all ([localhost/127.0.0.1, localhost/0:0:0:0:0:0:0:1])
2023-05-10 08:18:48,391 [INFO] [c.d.o.d.i.c.t.Clock.JanusGraph Session-admin-0] :: Using native clock for microsecond precision
2023-05-10 08:18:48,443 [WARN] [c.d.o.d.i.c.l.h.OptionalLocalDcHelper.JanusGraph Session-admin-0] :: [JanusGraph Session|default] You specified datacenter1 as the local DC, but some contact points are from a different DC: Node(endPoint=localhost/127.0.0.1:9042, hostId=null, hashCode=5fc66b67)=null; please provide the correct local DC, or check your contact points
2023-05-10 08:18:48,465 [INFO] [o.j.d.c.ExecutorServiceBuilder.main] :: Initiated fixed thread pool of size 40
2023-05-10 08:18:48,615 [INFO] [o.j.g.d.StandardJanusGraph.main] :: Gremlin script evaluation is disabled
2023-05-10 08:18:48,652 [INFO] [o.j.d.l.k.KCVSLog.main] :: Loaded unidentified ReadMarker start time 2023-05-10T13:18:48.652646Z into org.janusgraph.diskstorage.log.kcvs.KCVSLog$MessagePuller@74ea46e2
2023-05-10 08:18:48,723 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 08:18:50,619 [INFO] [Main.main] :: g.V().count().next(): 70005
2023-05-10 08:18:50,626 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 08:20:39,750 [WARN] [o.j.g.t.StandardJanusGraphTx.main] :: Query requires iterating over all vertices [[]]. For better performance, use indexes
2023-05-10 08:20:40,751 [INFO] [Main.main] :: g.V().count().next(): 0
2023-05-10 08:24:51,437 [WARN] [o.j.d.l.c.ConsistentKeyLocker.main] :: Discarded expired claim on KeyColumn [k=0x0x7800000000008080, c=0x0x02] with timestamp 2023-05-09T20:16:07.308532Z
2023-05-10 08:24:51,439 [WARN] [o.j.d.l.c.ConsistentKeyLocker.main] :: Discarded expired claim on KeyColumn [k=0x0x7800000000008180, c=0x0x02] with timestamp 2023-05-09T20:16:08.146591Z
2023-05-10 08:24:51,442 [WARN] [o.j.d.l.c.ConsistentKeyLocker.main] :: Discarded expired claim on KeyColumn [k=0x0x7800000000008280, c=0x0x02] with timestamp 2023-05-09T20:16:08.988543Z
...
2023-05-10 11:21:48,533 [ERROR] [o.j.g.d.StandardJanusGraph.main] :: Could not commit transaction [1] due to storage exception in commit
org.janusgraph.core.JanusGraphException: Could not execute operation due to backend exception
at org.janusgraph.diskstorage.util.BackendOperation.execute(BackendOperation.java:54) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.keycolumnvalue.cache.CacheTransaction.persist(CacheTransaction.java:96) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.keycolumnvalue.cache.CacheTransaction.flushInternal(CacheTransaction.java:147) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.keycolumnvalue.cache.CacheTransaction.commit(CacheTransaction.java:210) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.BackendTransaction.commitStorage(BackendTransaction.java:147) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.graphdb.database.StandardJanusGraph.commit(StandardJanusGraph.java:917) [janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.graphdb.transaction.StandardJanusGraphTx.commit(StandardJanusGraphTx.java:1558) [janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.graphdb.tinkerpop.JanusGraphBlueprintsGraph$GraphTransaction.doCommit(JanusGraphBlueprintsGraph.java:322) [janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.apache.tinkerpop.gremlin.structure.util.AbstractTransaction.commit(AbstractTransaction.java:104) [gremlin-core-3.6.2.jar:3.6.2]
at org.janusgraph.graphdb.tinkerpop.JanusGraphBlueprintsGraph$GraphTransaction.commit(JanusGraphBlueprintsGraph.java:300) [janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at Test3.main(Test3.java:20) [test-classes/:?]
Caused by: org.janusgraph.diskstorage.TemporaryBackendException: Could not successfully complete backend operation due to repeated temporary exceptions after PT1M40S
at org.janusgraph.diskstorage.util.BackendOperation.executeDirect(BackendOperation.java:98) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.util.BackendOperation.execute(BackendOperation.java:52) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
... 10 more
Caused by: org.janusgraph.diskstorage.locking.consistentkey.ExpiredLockException: Expired lock on KeyColumn [k=0x0xE000000000150A80, c=0x0x24]: lock timestamp 2023-05-10T16:16:48.301589Z Micros is older than storage.lock.expiry-time=PT5M
at org.janusgraph.diskstorage.locking.consistentkey.ConsistentKeyLocker.checkSingleLock(ConsistentKeyLocker.java:472) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.locking.consistentkey.ConsistentKeyLocker.checkSingleLock(ConsistentKeyLocker.java:131) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.locking.AbstractLocker.checkLocks(AbstractLocker.java:348) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.locking.consistentkey.ExpectedValueCheckingTransaction.checkAllLocks(ExpectedValueCheckingTransaction.java:178) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.locking.consistentkey.ExpectedValueCheckingTransaction.prepareForMutations(ExpectedValueCheckingTransaction.java:157) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.locking.consistentkey.ExpectedValueCheckingStoreManager.mutateMany(ExpectedValueCheckingStoreManager.java:77) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.keycolumnvalue.cache.CacheTransaction$1.call(CacheTransaction.java:99) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.keycolumnvalue.cache.CacheTransaction$1.call(CacheTransaction.java:96) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.util.BackendOperation.executeDirect(BackendOperation.java:66) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.util.BackendOperation.execute(BackendOperation.java:52) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
... 10 more
2023-05-10 11:21:48,543 [ERROR] [o.j.g.d.StandardJanusGraph.main] :: Could not commit transaction [1] due to exception
org.janusgraph.core.JanusGraphException: Could not execute operation due to backend exception
at org.janusgraph.diskstorage.util.BackendOperation.execute(BackendOperation.java:54) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.keycolumnvalue.cache.CacheTransaction.persist(CacheTransaction.java:96) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.keycolumnvalue.cache.CacheTransaction.flushInternal(CacheTransaction.java:147) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.keycolumnvalue.cache.CacheTransaction.commit(CacheTransaction.java:210) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.BackendTransaction.commitStorage(BackendTransaction.java:147) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.graphdb.database.StandardJanusGraph.commit(StandardJanusGraph.java:917) [janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.graphdb.transaction.StandardJanusGraphTx.commit(StandardJanusGraphTx.java:1558) [janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.graphdb.tinkerpop.JanusGraphBlueprintsGraph$GraphTransaction.doCommit(JanusGraphBlueprintsGraph.java:322) [janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.apache.tinkerpop.gremlin.structure.util.AbstractTransaction.commit(AbstractTransaction.java:104) [gremlin-core-3.6.2.jar:3.6.2]
at org.janusgraph.graphdb.tinkerpop.JanusGraphBlueprintsGraph$GraphTransaction.commit(JanusGraphBlueprintsGraph.java:300) [janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at Test3.main(Test3.java:20) [test-classes/:?]
Caused by: org.janusgraph.diskstorage.TemporaryBackendException: Could not successfully complete backend operation due to repeated temporary exceptions after PT1M40S
at org.janusgraph.diskstorage.util.BackendOperation.executeDirect(BackendOperation.java:98) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
at org.janusgraph.diskstorage.util.BackendOperation.execute(BackendOperation.java:52) ~[janusgraph-core-1.0.0-20230504-014643.988c094.jar:?]
... 10 more
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversalSource;
import org.janusgraph.core.JanusGraph;
import org.janusgraph.core.JanusGraphFactory;
import org.janusgraph.core.JanusGraphVertex;
public class Test5 {
private static final Logger logger = LogManager.getLogger(Main.class);
public static void main(String[] args) {
JanusGraph janusGraph = JanusGraphFactory.build().set("storage.backend", "cql").set("storage.hostname", "localhost:9042").open();
GraphTraversalSource g = janusGraph.traversal();
logger.info("g.V().count().next():\t" + g.V().count().next());
g.V().drop().iterate();
janusGraph.tx().commit();
logger.info("g.V().count().next():\t" + g.V().count().next());
JanusGraphVertex janusGraphVertex = janusGraph.addVertex();
janusGraph.close();
}
}