using janusGraph git code example : example-remotegraph
It works well when i going to create elements and do some query things.
But it report exception when update and delete...
java.util.concurrent.CompletionException: org.apache.tinkerpop.gremlin.driver.exception.ResponseException: Could not locate method: DefaultGraphTraversal.none()
at java.util.concurrent.CompletableFuture.reportJoin(CompletableFuture.java:375)
at java.util.concurrent.CompletableFuture.join(CompletableFuture.java:1934)
at org.apache.tinkerpop.gremlin.driver.ResultSet.one(ResultSet.java:107)
at org.apache.tinkerpop.gremlin.driver.ResultSet$1.hasNext(ResultSet.java:159)
at org.apache.tinkerpop.gremlin.driver.ResultSet$1.next(ResultSet.java:166)
at org.apache.tinkerpop.gremlin.driver.ResultSet$1.next(ResultSet.java:153)
at org.apache.tinkerpop.gremlin.driver.remote.DriverRemoteTraversal$TraverserIterator.next(DriverRemoteTraversal.java:142)
at org.apache.tinkerpop.gremlin.driver.remote.DriverRemoteTraversal$TraverserIterator.next(DriverRemoteTraversal.java:127)
at org.apache.tinkerpop.gremlin.driver.remote.DriverRemoteTraversal.nextTraverser(DriverRemoteTraversal.java:108)
at org.apache.tinkerpop.gremlin.process.remote.traversal.step.map.RemoteStep.processNextStart(RemoteStep.java:80)
at org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep.next(AbstractStep.java:128)
at org.apache.tinkerpop.gremlin.process.traversal.step.util.AbstractStep.next(AbstractStep.java:38)
at org.apache.tinkerpop.gremlin.process.traversal.Traversal.iterate(Traversal.java:203)
at org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal.iterate(GraphTraversal.java:2694)
at org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.GraphTraversal$Admin.iterate(GraphTraversal.java:178)
at org.apache.tinkerpop.gremlin.process.traversal.dsl.graph.DefaultGraphTraversal.iterate(DefaultGraphTraversal.java:48)
at org.janusgraph.example.GraphApp.deleteElements(GraphApp.java:301)
at org.janusgraph.example.GraphApp.runApp(GraphApp.java:350)
at org.janusgraph.example.RemoteGraphApp.main(RemoteGraphApp.java:227)
here is the code :
public void deleteElements() {
try {
if (g == null) {
return;
}
LOGGER.info("deleting elements");
// note that this will succeed whether or not pluto exists
g.V().has("name", "pluto").drop().iterate();
if (supportsTransactions) {
g.tx().commit();
}
} catch (Exception e) {
LOGGER.error(e.getMessage(), e);
if (supportsTransactions) {
g.tx().rollback();
}
}
}
emmm.....i thought i have fixed this problem.....
the only reason perhaps the library version used doesn't match the gremlin-server's version;
I tried to turn the gremlin driver library to 3.2.9 version, and it works well.
You need to use the same Tinkerpop version JanusGraph is using, as this is an incompatible change that was introduced in Tinkerpop
Related
I have two Debezium SQL Server connectors that have to connect to one database and publish two different tables. Their name and database.history.kafka.topic are unique. Still when adding the second one (using a POST request) I get below exceptions. I don't want to use a unique value for database.server.name which counterintuitively has been used for metric name.
java.lang.RuntimeException: Unable to register the MBean 'debezium.sql_server:type=connector-metrics,context=schema-history,server=mydatabase'
Caused by: javax.management.InstanceAlreadyExistsException: debezium.sql_server:type=connector-metrics,context=schema-history,server=mydatabase
We won't be using JMX/MBeans so it's okay to disable it, but the question is how. If there is a common way to do it for JVM please advise.
I even see below code in Debezium where it registers a MBean. Looking just at two first lines, it seems one way to bypass this issue is forcing ManagementFactory.getPlatformMBeanServer() to return null. So another way of asking the same question may be how to force ManagementFactory.getPlatformMBeanServer() return null?
public synchronized void register() {
try {
final MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
if (mBeanServer == null) {
LOGGER.info("JMX not supported, bean '{}' not registered", name);
return;
}
// During connector restarts it is possible that Kafka Connect does not manage
// the lifecycle perfectly. In that case it is possible the old metric MBean is still present.
// There will be multiple attempts executed to register new MBean.
for (int attempt = 1; attempt <= REGISTRATION_RETRIES; attempt++) {
try {
mBeanServer.registerMBean(this, name);
break;
}
catch (InstanceAlreadyExistsException e) {
if (attempt < REGISTRATION_RETRIES) {
LOGGER.warn(
"Unable to register metrics as an old set with the same name exists, retrying in {} (attempt {} out of {})",
REGISTRATION_RETRY_DELAY, attempt, REGISTRATION_RETRIES);
final Metronome metronome = Metronome.sleeper(REGISTRATION_RETRY_DELAY, Clock.system());
metronome.pause();
}
else {
LOGGER.error("Failed to register metrics MBean, metrics will not be available");
}
}
}
// If the old metrics MBean is present then the connector will try to unregister it
// upon shutdown.
registered = true;
}
catch (JMException | InterruptedException e) {
throw new RuntimeException("Unable to register the MBean '" + name + "'", e);
}
}
You should use a single Debezium SQL Server connector for this, and use the table.include.list property on the connector to list the two tables you want to capture.
https://debezium.io/documentation/reference/stable/connectors/sqlserver.html#sqlserver-property-table-include-list
I'm using this library:
"io.github.microutils:kotlin-logging:2.0.4"
with this logging implementation:
"ch.qos.logback:logback-classic:1.2.3"
In my code I call:
private val logger = KotlinLogging.logger{}
and then use this logger as follows:
logger.debug("message")
this runs fine until I try to debug my code at which point the following to two NoSuchMethodErrors pop up in the library:
private static IMarkerFactory bwCompatibleGetMarkerFactoryFromBinder() throws
NoClassDefFoundError {
try {
return StaticMarkerBinder.getSingleton().getMarkerFactory();
} catch (NoSuchMethodError var1) {
return StaticMarkerBinder.SINGLETON.getMarkerFactory();
}
}
And:
private static MDCAdapter bwCompatibleGetMDCAdapterFromBinder() throws
NoClassDefFoundError {
try {
return StaticMDCBinder.getSingleton().getMDCA();
} catch (NoSuchMethodError var1) {
return StaticMDCBinder.SINGLETON.getMDCA();
}
}
(the first time I try to log something)
Others on my team do not experience this issue. they are on macs, in case that matters.
If, I just continue running the code everything is fine as the exception is caught, but I don't want to hit continue twice anytime I want to debug. I'm willing to ignore exceptions if that is possible, or better yet, fix the underlying issue.
In nonreactive ElasticsearchRepository, there's a class AbstractElasticsearchRepository that does
try {
if (createIndexAndMapping()) {
createIndex();
putMapping();
}
} catch (Exception exception) {
LOGGER.warn("Cannot create index: {}", exception.getMessage());
}
Is there a different, more manual, setup for ReactiveElasticsearchRepository? My index mapping only gets created when creating a record and not on startup.
For reactive repositories this is implemented in 4.1.0-M1, so it will be available in the next release (or when using the milestone).
If you cannot switch to the milestone version, you will need to create a non-reactive client as well and do the createIndex and putMapping with this client.
I use for two providers for Entity Framework Core in my ASP.NET Core application. SqlServer for production mode and Sqlite for integration tests mode.
In my application DbContext, when an exception occurs during SaveChangesAsync, I catch it to know what kind of problem occurred. I do that to be able to detect unique index constraint violation for example.
I have the following problems: it seems that different exception types are created for Sqlite and SqlServer providers (SqlException and SqliteException). These exceptions have different ErrorCode so I have to always specify the two error codes if I want to detect one kind of error.
Did someone find any solution to easily manage usual relational database errors and to get the same exception handler work for many providers ?
More of that, do you have any solution to know what is the type of the entity throwing the exception or do we have to get it from the string Message included in the exception?
Thanks in advance for your answers
For SQL Server error codes, you can refer here: Database engine errors
For Sqlite error codes, you can refer here: Result and Error Codes
For getting the entity, you will not know that from SqlException. But you can catch more specific exceptions. For instance, DbUpdateConcurrencyException has an Entries property you can work with.
Reference: Resolving concurrency conflicts
Here is an example for an handling an auth error that might work for you:
try
{
⋮
}
catch (SqlException e)
{
foreach (SqlError sqlError in e.Errors)
{
switch (sqlError.Number)
{
case 10028:
{
HandleAuthError(e);
break;
}
⋮
}
}
}
catch (SqliteException e)
{
switch (e.SqliteErrorCode)
{
case 23:
{
HandleAuthError(e);
break;
}
⋮
}
}
private void HandleAuthError(SystemException e)
{
⋮
}
Note : In 3.0.1, a bug makes that Entries Collection is empty when a unique index constraint violation is raised... Supposed to be fixed in 3.1
I am new to JavaFX coding (in IntelliJ IDEA), and have been reading / searching all over on how to swap scenes in the main controller / container. I found jewelsea's answer in another thread (Loading new fxml in the same scene), but am receiving an error on the following code.
public static void loadVista(String fxml) {
try {
mainController.setVista(
FXMLLoader.load(VistaNavigator.class.getResource(fxml)));
} catch (IOException e) {
e.printStackTrace();
}
}
The error I am receiving is the following:
Error:(56, 27) java: method setVista in class sample.MainController cannot be applied to given types;
required: javafx.scene.Node
found: java.lang.Object
reason: actual argument java.lang.Object cannot be converted to javafx.scene.Node by method invocation conversion
I know other people have gotten this to work, but all I have done is create a new project and copy the code. Can anyone help me?
It looks like you are trying to compile this with JDK 1.7: the code will only work in JDK 1.8 (the difference here being the enhanced type inference for generic methods introduced in JDK 1.8).
You should configure IntelliJ to use JDK 1.8 instead of 1.7.
If you want to try to revert the code to be JDK 1.7 compatible, you can try to replace it with
public static void loadVista(String fxml) {
try {
mainController.setVista(
FXMLLoader.<Node>load(VistaNavigator.class.getResource(fxml)));
} catch (IOException e) {
e.printStackTrace();
}
}
(with the appropriate import javafx.scene.Node ;, if needed). Of course, there may be other incompatibilities since the code you are using is targeted at JDK 1.8.