Spring Boot 2.1 introduced log groups. A log group is a logical name for one or more loggers. We can define log groups in our application configuration. Then we can set the log level for a group, so all loggers in the group will get the same log level. This can be very useful to change a log level for multiple loggers that belong together with one setting. Spring Boot already provides two log groups by default: web and sql. In the following list we see which loggers are part of the default log groups:

To get an overview of all Gradle tasks in our project we need to run the tasks task. Since Gradle 5.1 we can use the --group option followed by a group name. Gradle will then show all tasks belonging to the group and not the other tasks in the project.

Suppose we have a Gradle Java project and want to show the tasks that belong to the build group:

In a previous post we learned how to include parts of a document in the generated output. The included parts are defined using tags. The start of a tag is defined in a comment with the format tag::_tagName_[] and the end has the format end::_tagName_[]. Next we must use the tags attribute for the include macro followed by the tagName. If we don’t want to include a tag we must prefix it with an exclamation mark (!).

Cucumber-JVM is a framework for writing end to end tests in natural language, with each line backed by a Java method. Each Java method has a regular expression of natural language lines to match, and lines should only match one such pattern. On a recent assignment I was tasked with modernizing a fairly large cucumber test suite, and going through the steps I found a lot of Java methods that were not being called from the natural language feature files anymore. To identify and remove these unused steps, and prevent any new unused steps in the future, I contributed the following plugin to Cucumber 4.4.0 through: - https://github.com/cucumber/cucumber-jvm/pull/1648 - https://github.com/cucumber/cucumber-jvm/pull/1634

It can be run easily through:

Since Java 9 we can specify that the Javadoc output must be generated in HTML 5 instead of the default HTML 4. We need to pass the option -html5 to the javadoc tool. To do this in Gradle we must add the option to the javadoc task configuration. We use the addBooleanOption method of the options property that is part of the javadoc task. We set the argument to html5 and the value to true.

In the following example we reconfigure the javadoc task to make sure the generated Javadoc output is in HTML 5:

Recently we updated one of our internal applications from Spring Boot 1.5 to 2.1, which includes an update of Spring Security. After the update the OAuth2 security started to fail in the backend, it stopped recognizing the authentication.

One of the most important features in Gradle is the support for incremental tasks. Incremental tasks have input and output properties that can be checked by Gradle. When the values of the properties haven’t changed then the task can be marked as up to date by Gradle and it is not executed. This makes a build much faster. Input and output properties can be files, directories or plain object values. We can set a task input property with a date or date/time value to define when a task is up to date for a specific period. As long as the value of the input property hasn’t changed (and of course also the other input and output property values) Gradle will not rerun task and mark it as up to date. This is useful for example if a long running task (e.g. large integration test suite) only needs to run once a day or another period.

In the following example Gradle build file we define a new task Broadcast that will get content from a remote URL and save it in a file. In our case we want to save the latest messages from SDKMAN!. If you don’t know SKDMAN! you should check it out!. The Broadcast task has an incremental task output property, which is the output file of the task:

When building a service in gRPC you define the message and service definition in a .proto file. gRPC generates client, server and DTO implementations automatically for you in multiple languages. At the end of this post you will understand how to make your gRPC API also accessible via HTTP JSON by using Envoy as a transcoding proxy. You can test it out yourself by running the Java code in the attached github repo. For a quick introduction on gRPC itself, please read gRPC as an alternative to REST.