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Using Multiple Dynamic Caches With Spring

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In a third post about cache managers in spring (over a long period of time), I’d like to expand on the previous two by showing how to configure multiple cache managers that dynamically create caches. Spring has CompositeCacheManager which, in theory, should allow using more than one cache manager. It works by asking the underlying cache managers whether they have ...

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Build Reactive REST APIs with Spring WebFlux – Part3

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In continuation of the last article, we will see an application to expose reactive REST APIs. In this application, we used, Spring Boot with WebFluxSpring Data for Cassandra with Reactive SupportCassandra Database Below is the high-level architecture of the application. Let us look at the build.gradle file to see what dependencies are included to work with the Spring WebFlux. plugins { ...

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Vaadin Tip: Lazy Loading and Item Identity

Lazy Loading When using grids, trees or any other of multi-valued component with Vaadin you often want to display data from a database table and typically you have more than a few rows in the database. In this case loading thousands or even millions of records don’t make sense and would be a huge performance problem. For this use case ...

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Build Reactive REST APIs with Spring WebFlux – Part2

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In continuation of the last post, in this article, we will see the reactive streams specification and one of its implementation called Project Reactor. Reactive Streams specification has the following interfaces defined. Let us see the details of those interfaces. Publisher → A Publisher is a provider of a potentially unlimited number of sequenced elements, publishing them as requested by ...

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Test Coverage Reports For Maven Projects In SonarQube 8.3.x

Some years ago I write a blog post about how to generate test reports in SonarQube separate in test report for unit tests and for integration tests. Since SonarQube 6.2 the test report isn’t separate in these categories any more (see SonarQube’s blog post). SonarQube merges all test reports to one test report with an overall coverage. So how to ...

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Supersonic Subatomic GraphQL

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MicroProfile GraphQL is now included in the just released version 1.5.0 of Quarkus. You can now use code.quarkus.io to get going with Quarkus and include the SmallRye GraphQL Extension. This will create a Quarkus starter application with the following dependencies: <dependency> <groupId>io.quarkus</groupId> <artifactId>quarkus-resteasy</artifactId> </dependency> <dependency> <groupId>io.quarkus</groupId> <artifactId>quarkus-junit5</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>io.rest-assured</groupId> <artifactId>rest-assured</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>io.quarkus</groupId> <artifactId>quarkus-smallrye-graphql</artifactId> </dependency> NOTE: At ...

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Apache Camel K 1.0 is here – Why should you care

Yesterday we released Apache Camel K 1.0 and it was announced on social media and on the Camel website. So what is Camel K and why should you care? That is a great question and I want to help answer this by referring to great minds. Hugo Guerrero posted the following tweet   That is a powerful statement from Hugo, ...

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AWS CloudFormation: Target Group does not have an associated Load Balancer

java-interview-questions-answers

Yesterday I was using an AWS CloudFormation template to ultimately create an ECS Service (Fargate type), but also create resources including an Application Load Balancer, Target Group and IAM Roles. When the stack was being created, I received the following error: The target group with targetGroupArn arn:aws:elasticloadbalancing:us-east-1:599074885545:targetgroup/a204516-S2S-Sandbox-TargetGroup/9f4aa2eb4051a952 does not have an associated load balancer. (Service: AmazonECS; Status Code: 400; Error ...

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