Kubernetes is a system for running and coordinating containerized applications across a cluster of machines. Minikube runs a single-node Kubernetes cluster and can be used for local development. In this blog post I’ll compare 2 different ways to get a working Minikube environment on Windows based on experience with a […]
Maarten Smeets
Maarten is a software architect and Oracle ACE. Over the past years he has worked for numerous customers in the Netherlands in developer, analyst and architect roles on topics like software delivery, performance, security and other integration related challenges. Maarten is passionate about his job and likes to share his knowledge through publications, frequent blogging and presentations.
JVM performance: OpenJ9 uses least memory. GraalVM most. OpenJDK distributions differ
In a previous blog post I created a setup to compare JVM performance of several JVMs. I received some valuable feedback on the measures I conducted and requests to add additional JVMs. In this second post I’ll look at some more JVMs and I’ve added some measures like process memory […]
Comparing JVM performance; Zulu OpenJDK, OpenJDK, Oracle JDK, GraalVM CE
There are many different choices for a JVM for your Java application. Which would be the best to use? This depends on various factors. Performance being an important one. Solid performance research however is difficult. In this blog I’ll describe a setup I created to perform tests on different JVMs […]
Monitoring Spring Boot applications with Prometheus and Grafana
In order to compare the performance of different JDKs for reactive Spring Boot services, I made a setup in which a Spring Boot application is wrapped in a Docker container. This makes it easy to create different containers for different JDKs with the same Spring Boot application running in it. […]
Running Reactive Spring Boot on GraalVM in Docker
GraalVM is an open source polyglot VM which makes it easy to mix and match different languages such as Java, Javascript and R. It has the ability (with some restrictions) to compile code to native executables. This of course offers great performance benefits. Recently, GraalVM Docker files and images have […]
Securing Oracle Service Bus REST services with OAuth2 client credentials flow (without using additional products)
OAuth2 is a popular authentication framework. As a service provider it is thus common to provide support for OAuth2. How can you do this on a plain WebLogic Server / Service Bus without having to install additional products (and possibly have to pay for licenses)? If you just want to […]
Docker host and bridged networking. Running library/httpd on different ports
Docker provides different networking options. When using the Docker host networking, you don’t have the option to create port mappings. When using images like library/httpd:2.4, you don’t have the option to update the port on which it runs; it runs by default on port 80. Suppose you want to use […]
Running Spring Tool Suite and other GUI applications from a Docker container
Running an application within a Docker container helps in isolating the application from the host OS. Running GUI applications like for example an IDE from a Docker container, can be challenging. I’ll explain several of the issues you might encounter and how to solve them. For this I will use […]
Automate the installation of Oracle JDK 8 and 10 on RHEL and Debian derivatives
Automating the Oracle JDK installation on RHEL derivatives (such as CentOS, Oracle Linux) and Debian derivatives (such as Mint, Ubuntu) differs. This is due to different package managers and repositories. In this blog I’ll provide quick instructions on how to automate the installation of Oracle JDK 8 and 10 on […]
VirtualBox networking explained
VirtualBox networking is extremely flexible. With this flexibility comes the challenge of making the correct choices. In this blog, the different options are explained and some example use cases are elaborated. Access between guests, host and other members of the network is explained and the required configuration is shown. This […]
How to securely access remote content without using a VPN: Use a proxy server accessed through an SSH tunnel
There are numerous occasions that I was limited in my work because of connectivity which could not be trusted. For example; I could not download large installers due to a proxy anti virus tool which manipulated downloads causing files to become corrupted. I needed to visit a website to find […]
SOA Suite 12c in Docker containers. Only a couple of commands, no installers, no third party scripts
For developers, installing a full blown local SOA Suite environment has never been a favorite (except for a select few). It is time consuming and requires you to download and run various installers after each other. If you want to start clean (and you haven’t taken precautions), it could be […]
Running Spring Boot in a Docker container on OpenJDK, Oracle JDK, Zulu on Alpine Linux, Oracle Linux, Ubuntu
Spring Boot is great for running inside a Docker container. Spring Boot applications ‘just run’. A Spring Boot application has an embedded servlet engine making it independent of application servers. There is a Spring Boot Maven plugin available to easily create a JAR file which contains all required dependencies. This […]
Application Container Cloud Service (ACCS): Using the Application Cache from a Spring Boot application
Spring Boot allows you to quickly develop microservices. Application Container Cloud Service (ACCS) allows you to easily host Spring Boot applications. Oracle provides an Application Cache based on Coherence which you can use from applications deployed to ACCS. In order to use the Application Cache from Spring Boot, Oracle provides […]
Java: How to fix Spring @Autowired annotation not working issues
Spring is a powerful framework, but it requires some skill to use efficiently. When I started working with Spring a while ago (actually Spring Boot to develop microservices) I encountered some challenges related to dependency injection and using the @Autowired annotation. In this blog I’ll explain the issues and possible […]
Automate calls to SOAP and REST webservices using simple Python scripts
Probably not many people will tell you running batches over webservices is a good idea. Sometimes though, it can be handy to have a script available to generate webservice calls based on a template message with variables and automate processing the response messages. In addition, if you have a large […]
Getting started with Spring Boot microservices. Why and how.
In order to quickly develop microservices, Spring Boot is a common choice. Why should I be interested in Spring Boot? In this blog post I’ll give you some reasons why looking at Spring Boot is interesting and give some samples on how to get started quickly. I’ll shortly talk about […]
Getting started with Oracle Database in a Docker container!
One of the benefits of using Docker is quick and easy provisioning. I wanted to find out first-hand if this could help me get an Oracle Enterprise Edition database quickly up and running for use in a development environment. Oracle provides Docker images for its Standard and Enterprise Edition database […]
10 reasons NOT to implement Blockchain now
A secure distributed ledger with smart contract capabilities not requiring a bank as an intermediary! Also a single source of truth with complete traceability. Definitely something we want! Blockchain technology promises to make this possible. Blockchain became famous through cryptocurrency like Bitcoin and Ethereum. The technology could also be considered […]
Quickly create a Virtualbox development VM with XE DB using Kickstart, Packer, Vagrant
The topic of quickly creating an Oracle development VM is not new. Several years ago Edwin Biemond and Lucas Jellema have written several blogs about this and have given presentations about the topics at various conferences. You can also download ready made Virtualbox images from Oracle here and specifically for […]
Oracle SOA Suite and WebLogic: Overview of key and keystore configuration
Keystores and the keys within can be used for security on the transport layer and application layer in Oracle SOA Suite and WebLogic Server. Keystores hold private keys (identity) but also public certificates (trust). This is important when WebLogic / SOA Suite acts as the server but also when it […]
R and the Oracle database: Using dplyr / dbplyr with ROracle on Windows 10
R uses data extensively. Data often resides in a database. In this blog I will describe installing and using dplyr, dbplyr and ROracle on Windows 10 to access data from an Oracle database and use it in R.
Oracle Mobile Cloud Service (MCS): Overview of integration options
Oracle Mobile Cloud Service has a lot of options which allows it to integrate with other services and systems. Since it runs JavaScript on Node.js for custom APIs, it is very flexible. Some features allow it to extent its own functionality such as the Firebase configuration option to send notifications […]
Oracle Mobile Cloud Service (MCS) and Integration Cloud Service (ICS): How secure is your TLS connection?
In a previous blog I have explained which what cipher suites are, the role they play in establishing SSL connections and have provided some suggestions on how you can determine which cipher suite is a strong cipher suite. In this blog post I’ll apply this knowledge to look at incoming […]
SSL/TLS: How to choose your cipher suite
For SSL/TLS connections, cipher suites determine for a major part how secure the connection will be. A cipher suite is a named combination of authentication, encryption, message authentication code (MAC) and key exchange algorithms used to negotiate the security settings (here). But what does this mean and how do you […]
Oracle SOA Suite: Want performance? Don’t log so much and clean up your database!
The Oracle SOA Suite infrastructure, especially composites, use the database intensively. Not only are the process definitions stored in the database, also a lot of audit information gets written there. The SOA infrastructure database, if not well managed, will grow and will eventually have detrimental effects on performance. In this […]
Oracle SOA Suite: Two-way SSL with TLS1.2 made easy (slightly less complicated)
Transport layer security (TLS) is not an easy topic. Many blogs have been written about this already. Surprisingly though, I did not find a single blog which was more or less complete and provided me with everything I needed to know to get this working on SOA Suite 12.2.1. In […]
R: Utilizing multiple CPUs
R is a great piece of software to perform statistical analyses. Computing power can however be a limitation. R by default uses only a single CPU. In almost every machine, multiple CPUs are present, so why not utilize them? In this blog post I’ll give a minimal example and some […]
Oracle Mobile Cloud Service (MCS): An introduction to API security: Basic Authentication and OAuth2
As an integration/backend developer, when starting a project using Mobile Cloud Service, it is important to have some understanding of what this MBaaS (Mobile Backend as a Service) has to offer in terms of security features. This is important in order to be able to configure and test MCS. In […]
Machine learning: Getting started with random forests in R
According to Gartner, machine learning is on top of the hype cycle at the peak of inflated expectations. There is a lot of misunderstanding about what machine learning actually is and what it can be done with it. Machine learning is not as abstract as one might think. If you […]
Oracle SOA Suite: Find that composite instance!
When executing BPM or BPEL processes, they are usually executed in the context of a specific entity. Sometimes you want to find instances involved with a specific entity. There are different ways to make this easy. You can for example use composite instance titles or sensors and set them to […]
Oracle Service Bus: Produce messages to a Kafka topic
Oracle Service Bus is a powerful tool to provide features like transformation, throttling, virtualization of messages coming from different sources. There is a (recently opensourced!) Kafka transport available for Oracle Service Bus (see here). Oracle Service Bus can thus be used to do all kinds of interesting things to messages […]
Oracle Service Bus: Pipeline alerts in Splunk using SNMP traps
Oracle Service Bus provides a reporting activity called Alert. The OSB pipeline alerts use a persistent store. This store is file based. Changing the persistent store to JDBC based, does not cause pipeline alerts to be stored in a database instead of on disk. When the persistent store on disk […]
Ubuntu VM in VirtualBox: How to increase the size of a disk and make small(er) exports for distribution
Sometimes I create a VirtualBox disk for usage in a VM with a certain size. I think it will be enough for what I want to use the VM for. After using the VM for a while, it happens (often) that I need more space than I initially assigned. For […]
WebLogic Server: Logging the SOAP action in the access.log
WebLogic Server allows you to customize your access.log. This can be very powerful if you want to monitor for example service response times in a tool like Splunk (see here). When working with SOAP services though, especially those with many operations, it can be insufficient to monitor services to the […]
Oracle Mobile Cloud Service (MCS). Implementing custom APIs using JavaScript on Node.js
Oracle Mobile Cloud Service is a mobile backend as a service. MCS does its magic by providing a lot of features to make implementing mobile services easy such as (among many others) authentication, logging/analytics, lookups and calling other services. There are also features available to make integration with mobile clients […]
WebLogic Server: Automate obtaining performance metrics from the DMS
Oracle provides the Dynamic Monitoring Service (DMS) as part of WebLogic Server which is extremely useful if you want to obtain aggregated data of an environment in case of for example a performance test. The data which can be obtained from DMS is extensive. This varies from average duration of […]
Oracle Service Bus: A quickstart for the Kafka transport
As mentioned on the following blog post by Lucas Jellema, Kafka is going to play a part in several Oracle products. For some usecases it might eventually even replace JMS. In order to allow for easy integration with Kafka, you can use Oracle Service Bus to create a virtualization layer […]
Sonatype Nexus 2.x: Using the REST API to clean-up your repository
Sonatype provides Nexus. An extensive artifact Repository Manager. It can hold large amounts of stored artifacts and still requests get processed quickly. Also it has an extensive easy to use API which is a definite asset. When a project has been running for a longer period (say years), the repository […]
Sonatype Nexus 3.0. Using the new Groovy API
Sonatype Nexus 3.0 does not have the REST API which was available in Nexus 2.x (see the discussion here). This provides a challenge in case you want to automate certain tasks. Nexus 3 does provide a Groovy API however which allows you to write your own scripts and upload them […]