https://pieterjd.github.io/posts/Recent content in Posts on pieterjd.beHugo -- gohugo.ioen-usThis work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.Wed, 21 Feb 2024 07:29:12 +0000https://pieterjd.github.io/posts/jq-regex/Wed, 21 Feb 2024 07:29:12 +0000https://pieterjd.github.io/posts/jq-regex/I needed to go through the properties of a JSON object and filter out the desired ones. Although not a big object, I didn&rsquo;t feel like doing it by hand. A nice use-case for JQ!https://pieterjd.github.io/posts/decorator-httpclient/Mon, 19 Feb 2024 12:34:00 +0000https://pieterjd.github.io/posts/decorator-httpclient/The out of the box HttpClient available since Java 11 is great, but is lacking caching. How to add this in a clean way? Welcom to the Decorator Design Pattern!https://pieterjd.github.io/posts/this-algorithm-is-1606240-percent-faster/Sat, 25 Nov 2023 07:10:23 +0200https://pieterjd.github.io/posts/this-algorithm-is-1606240-percent-faster/It is all in the title, but in this post I&rsquo;ll go deeper how to represent encountered characters using bits.https://pieterjd.github.io/posts/wiremock-in-2-minutes/Wed, 04 Oct 2023 07:10:23 +0200https://pieterjd.github.io/posts/wiremock-in-2-minutes/Wiremock helps you mock APIs, but how to get started? Two examples, two minutes of your time.https://pieterjd.github.io/posts/sentry-sprint-boot-global-handler/Fri, 30 Jun 2023 14:03:05 +0200https://pieterjd.github.io/posts/sentry-sprint-boot-global-handler/Adding <code>sentry.io</code> is quite straightforward, but how do you add a global handler?https://pieterjd.github.io/posts/fallback-mechanism-with-streams/Wed, 28 Jun 2023 16:45:31 +0200https://pieterjd.github.io/posts/fallback-mechanism-with-streams/The Problem I would like to summarize Person objects. Use the lastName if it is not null; if null, then use the firstName; else use the birthDay. If all these are null , then use the default text UNKNOWN. Usually, you write something like this: String summary = &#34;&#34;; if(p.getLastName() != null){ summary = p.getLastName(); } else if(p.getFirstName() != null){ summary = p.getFirstName(); } else if (p.getBirthDate() != null){ summary = p.https://pieterjd.github.io/posts/java-stream-advanced-grouping/Mon, 22 May 2023 17:02:49 +0200https://pieterjd.github.io/posts/java-stream-advanced-grouping/The problem I have a list of Person objects. I would like to group them per birth month, and only keep a List of lastnames. I came up with this code from memory Map&lt;String, List&lt;Person&gt;&gt; personsByMonth = persons.stream() .collect(Collectors.groupingBy(Person::getBirthMonth)); System.out.println(personsByMonth); And you get the following output (truncated for readability): {JUNE=[Person{lastName='Doe 11', birthDate=2022-06-07}], JANUARY=[Person{lastName='Doe 10', birthDate=2023-01-26}]} But how do I get rid of the redundant information? The solution The Collectors class provides quite a lot of variation of the groupingBy method.https://pieterjd.github.io/posts/cli-xml-formatting-highlighting/Mon, 08 May 2023 17:06:43 +0200https://pieterjd.github.io/posts/cli-xml-formatting-highlighting/When working on legacy projects, you come across XML. And you would like some querying, highlighting and formatting to make your life less annoying.https://pieterjd.github.io/posts/comparator-and-null/Wed, 03 May 2023 18:27:23 +0200https://pieterjd.github.io/posts/comparator-and-null/Sorting collections has been quite easy with the <code>Comparator</code> class. But how do you deal with possible <code>null</code> values in for instance a <code>List</code>? You probably see already the <code>NullPointerException</code>s fly around, but fear not!https://pieterjd.github.io/posts/jpa-native-updates/Mon, 01 May 2023 19:25:31 +0200https://pieterjd.github.io/posts/jpa-native-updates/The point of JPA is define mappings so you don&rsquo;t have to deal with low level SQL/JDBC statements anymore. In exceptional cases you can&rsquo;t rely on the high level JPQL.