I have below code and it complies fine. On run time it gives Exception in thread "main" java.lang.StackOverflowError.
The reason could be recursive object creation.
But my question is in this case we should get OutOfMemory Error. Then why we are getting StackOverflowError.
public class MainClass {
MainClass m = new MainClass();
public static void main(String a[]) throws Exception {
MainClass mc = new MainClass();
mc.getHello();
}
public void getHello(){
System.out.println("Hello");
}
}
Thanks in advance
Because your constructor calls itself.
That's the definition of a stack overflow.
Related
I have two application e.g) A, B
A has a Saga
B is just web application
A sent Command messages to B and
B sent exception for that Command to A's Saga and A's Saga received well
and B have a #ExceptionHandler which I hope to be invoked but it's not working
How can I make them be invoked?
EDIT
this is A application's Saga that sends command messages to B application
and deals with exception which B sent
#Saga
public class OrderSaga {
#Autowired
private transient CommandGateway commandGateway;
#StartSaga
#SagaEventHandler(associationProperty = "orderId")
public void handle(CreateOrderEvent evt) {
String paymentId = UUID.randomUUID().toString();
SagaLifecycle.associateWith("paymentId", paymentId);
commandGateway.send(new CreatedPaymentCommand(paymentId, evt.getUserId(),evt.getFoodPrice())).exceptionally(exp -> {
System.out.println("got it");
System.out.println(exp.getMessage());
return null;
});
}
}
this is B application that throws exception for test
#Aggregate
#NoArgsConstructor
public class PaymentAggregate {
#AggregateIdentifier
private String paymentId;
private String userId;
private PaymentStatus status;
#CommandHandler
public PaymentAggregate(CreatedPaymentCommand cmd) {
throw new IllegalStateException("this exception was came from payment aggregates");
// AggregateLifecycle.apply(new CreatedPaymentEvent(cmd.getPaymentId(),
// cmd.getUserId(),cmd.getMoney()));
}
#ExceptionHandler(resultType = IllegalStateException.class)
public void error(IllegalStateException exp) {
System.out.println(exp.getMessage());
}
// I want this #ExceptionHandler to be invoked
#EventSourcingHandler
public void on(CreatedPaymentEvent evt) {
this.paymentId = evt.getPaymentId();
this.userId = evt.getUserId();
}
}
A application catch exception well like below
2021-08-24 11:46:43.534 WARN 14244 --- [ault-executor-2] o.a.c.gateway.DefaultCommandGateway : Command 'com.common.cmd.CreatedPaymentCommand' resulted in org.axonframework.commandhandling.CommandExecutionException(this exception was came from payment aggregates)
got it
this exception was came from payment aggregates
but B is not I thought that B's #ExceptionHandler will catch that exception
in short, How can I make B's #ExceptionHandler to be invoked
It doesn't work right now because the exception is thrown from the constructor of your aggregate.
As you are using a constructor command handler, there is no instance present yet.
And without an instance, Axon Framework cannot spot the #ExceptionHandler annotated method you've set up.
This is the only missing point for the exception handlers at this stage. Honestly, the reference guide should be a bit more specific about this. I am sure this will change in the future, though.
There's a different approach for having a command handler that constructs the aggregate and that can use the #ExceptionHandler: with the #CreationPolicy annotation. The reference guide has this to say about it, by the way.
Thus, instead of having a constructor command handler, you would set up a regular command handler using the AggregateCreationPolicy.ALWAYS.
That would adjust your sample like so:
#Aggregate
#NoArgsConstructor
public class PaymentAggregate {
#AggregateIdentifier
private String paymentId;
private String userId;
private PaymentStatus status;
#CommandHandler
#CreationPolicy(AggregateCreationPolicy.ALWAYS)
public void handle(CreatedPaymentCommand cmd) {
throw new IllegalStateException("this exception was came from payment aggregates");
// AggregateLifecycle.apply(new CreatedPaymentEvent(cmd.getPaymentId(),
// cmd.getUserId(),cmd.getMoney()));
}
#ExceptionHandler(resultType = IllegalStateException.class)
public void error(IllegalStateException exp) {
System.out.println(exp.getMessage());
}
// I want this #ExceptionHandler to be invoked
#EventSourcingHandler
public void on(CreatedPaymentEvent evt) {
this.paymentId = evt.getPaymentId();
this.userId = evt.getUserId();
}
}
Please give this a try in your application, #YongD.
I am trying to mockStatic method using PowerMockito , where I tried some options to mockStatic for a class, resulting in different exceptions.
#RunWith(PowerMockRunner.class)
#PrepareForTest({Base64.class})
public class BqClientFactoryTest {
#Test
public void testGetBigQueryClient() throws Exception {
mockStatic(Base64.class);
Base64.Decoder mockDecoder = mock(Base64.Decoder.class);
when(Base64.getDecoder()).thenReturn(mockDecoder);
This resulted in org.mockito.exceptions.misusing.MissingMethodInvocationException:
I used another example like this
#RunWith(PowerMockRunner.class)
#PrepareForTest({Base64.class})
public class BqClientFactoryTest {
#Test
public void testGetBigQueryClient() throws Exception {
mockStatic(Base64.class);
Base64.Decoder mockDecoder = mock(Base64.Decoder.class);
doReturn(mockDecoder).when(Base64.class, "getDecoder");
which gives me
org.mockito.exceptions.misusing.UnfinishedStubbingException:
Unfinished stubbing detected here:
If I use
BDDMockito.given(Base64.getDecoder()).willReturn(mockDecoder);
from Mocking static methods with Mockito , it still returns org.mockito.exceptions.misusing.MissingMethodInvocationException
I tried to check similar questions on SO, they haven't seemed to help.
Any help resolving this is appreciated.
I solved it following this, all other solutions didn't work for me. It is difficult to search for this solution, since there are too many on SO on the same.
PowerMockito mock single static method and return object inside another static method , PowerMock, mock a static method, THEN call real methods on all other statics
#RunWith(PowerMockRunner.class)
#PrepareForTest({Base64.class})
public class BqClientFactoryTest {
#Test
public void testGetBigQueryClient() throws Exception {
Base64.Decoder mockDecoder = mock(Base64.Decoder.class);
stub(method(Base64.class, "getDecoder")).toReturn(mockDecoder);
Picocli has to introspect the command tree. Doing so it needs to load the domain object classes for every Command which slows down the jvm startup.
What options are there to avoid this startup lag? One solution I've come up with is described in https://github.com/remkop/picocli/issues/482:
I am using reflection to postpone any class loading until after the command is selected. This way only the command classes themselves are loaded and finally the classes which implement the single command requested by the user:
abstract class BaseCommand implements Runnable {
interface CommandExecutor {
Object doExecute() throws Exception;
}
// find the CommandExecutor declared at the BaseCommand subclass.
protected Object executeReflectively() throws Exception {
Class<?> innerClass = getExecutorInnerClass();
Constructor<?> ctor = innerClass.getDeclaredConstructor(getClass());
CommandExecutor exec = (CommandExecutor) ctor.newInstance(this);
return exec.doExecute();
}
private Class<?> getExecutorInnerClass() throws ClassNotFoundException {
return getClass().getClassLoader().loadClass(getClass().getName() + "$Executor");
}
public void run() {
try {
executeReflectively();
} catch(...){
/// usual stuff
}
}
}
A concrete commend class:
#Command(...)
final class CopyProfile extends BaseCommand {
#Option String source;
#Option String dest;
// class must NOT be static and must be called "Executor"
public class Executor implements CommandExecutor {
#Override
public Object doExecute() throws Exception {
// you can basically wrap your original run() with this boilerplate
// all the CopyProfile's field are in scope!
FileUtils.copy(source, dest);
}
}
}
It seems like https://github.com/remkop/picocli/issues/500 may provide the ultimate solution to this. What are the other options until then?
UPDATE February 2020:
Upgrading to a recent version of picocli should fix this issue.
From the picocli 4.2.0 release notes:
From this release, subcommands are not instantiated until they are matched on the command line. This should improve the startup time for applications with subcommands that do a lot of initialization when they are instantiated.
An alternative that doesn’t require any code changes is to use GraalVM to compile your picocli-based application to a native image.
This article shows how to do this and the resulting startup time is 3 milliseconds.
One operator deleted Data Dictionary and restarted Alfresco 3.4.12 Enterprise Edition. The context /alfresco doesn't start with the following exception:
17:43:11,100 INFO [STDOUT] 17:43:11,097 ERROR [web.context.ContextLoader] Context initialization failed
org.alfresco.error.AlfrescoRuntimeException: 08050000 Failed to find 'app:dictionary' node
at org.alfresco.repo.action.scheduled.ScheduledPersistedActionServiceImpl.locatePersistanceFolder(ScheduledPersistedActionServiceImpl.java:132)
Looking at the source code in org.alfresco.repo.action.scheduled.ScheduledPersistedActionServiceImpl.java, the path is hardwired.
Then we followed the tip from https://community.alfresco.com/thread/202859-error-failed-to-find-appdictionary-node, editing bootstrap-context.xml, comment out the class.
After the change the error went over, now the RenditionService couldn't start.
We're looking for a way to recover the deleted node, since we can obtain the nodeid from the database. So we created a small class and invoke it through spring in bootstrap-context.xml, but it's failing due to permissions. Could you take a look at the code and tell us what's wrong. The code is:
package com.impulseit.test;
import javax.transaction.UserTransaction;
import org.alfresco.repo.node.archive.NodeArchiveService;
import org.alfresco.repo.node.archive.RestoreNodeReport;
import org.alfresco.repo.security.authentication.AuthenticationUtil;
import org.alfresco.repo.security.authentication.AuthenticationUtil.RunAsWork;
import org.alfresco.service.ServiceRegistry;
import org.alfresco.service.cmr.repository.NodeRef;
public class RestoreNode {
private NodeArchiveService nodeArchiveService;
private ServiceRegistry serviceRegistry;
private String nodeName ="archive://SpacesStore/adfc0cfe-e20b-467f-ad71-253aea8f9ac9";
public void setNodeArchiveService(NodeArchiveService value)
{
this.nodeArchiveService = value;
}
public void setServiceRegistry(ServiceRegistry value)
{
this.serviceRegistry = value;
}
public void doRestore() {
RunAsWork<Void> runAsWork = new RunAsWork<Void>()
{
public Void doWork() throws Exception
{
NodeRef nodeRef = new NodeRef(nodeName);
//RestoreNodeReport restoreNodeReport =
UserTransaction trx_A = serviceRegistry.getTransactionService().getUserTransaction();
trx_A.begin();
AuthenticationUtil.setFullyAuthenticatedUser(AuthenticationUtil.getSystemUserName());
RestoreNodeReport restored = nodeArchiveService.restoreArchivedNode(nodeRef);
trx_A.commit();
return null;
}
};
AuthenticationUtil.runAs(runAsWork,AuthenticationUtil.getSystemUserName());
}
public RestoreNode() {
}
}
The exception is:
19:31:21,747 User:admin ERROR [node.archive.NodeArchiveServiceImpl] An unhandled exception stopped the restore
java.lang.NullPointerException
at org.alfresco.repo.security.permissions.impl.model.PermissionModel.getPermissionReference(PermissionModel.java:1315)
at org.alfresco.repo.security.permissions.impl.PermissionServiceImpl.getPermissionReference(PermissionServiceImpl.java:956)
at org.alfresco.repo.security.permissions.impl.PermissionServiceImpl.hasPermission(PermissionServiceImpl.java:976)
Thank you in advance.
Luis
I have created AdvancedRobot. After first round in Run() I have got exceptions from Ahead method.
public override void Run()
{
//...
var moveAmount = Math.Max(BattleFieldWidth, BattleFieldHeight);
Ahead(moveAmount);
//...
}
The exceptions are:
System.InvalidCastException: „Unable to cast object of type 'net.sf.robocode.dotnet.peer.ExecCommands' to type 'net.sf.robocode.dotnet.peer.ExecResults'.”
and
java.lang.Throwable;
StackTrace „($exception).StackTrace”:
„System.InvalidCastException” {System.InvalidCastException}
Source "jni4net.n-0.8.7.0"
As a result my robot has a label "Disabled" and doesn't move.
Have you got any ideas?
I use Robocode for .NET.