Posts Tagged “java”
Say I have these numbers in an array, for example: I want to do something with that set of numbers, such as taking out null values, and extracting only the odd ones. Too take it further, maybe I want an even number or two mixed in the processed list as well. So I have this…
Did a simple, customized SQL query builder that’s only specific for UPDATE statements some time early last year. Thought I’d just write it down here. It was a smaller part of a bigger application. It wasn’t required for all update cases, but a number of them did. I’ve mostly re-written it from memory. It should…
I recently started on the path on building content on the fly that gets sent out as soon as possible, using a template engine, but from a back-end perspective. If that makes sense? This is for an event-driven application that sits there and listens for incoming messages. A simple one. Consume the message as soon…
From time to time I get some of this odd API response from requesting information for a specific something. I expect the response data to be a simple JSON object. Instead I am looking at a JSON array. I suppose that is still simple enough and it’s not so odd. This kind of response happens…
Somebody asked me recently why their POJO validator was not working as expected. They had already followed the “code I wrote” down to a T. Emphasis on the quotes, because trust me that block of code for bean validation they used as reference from an older project I did, was pretty much a very trivial…
There is this Java library that I utilize to quickly get values from JSON objects that is fairly easy to use. This would be Jayway JsonPath. More can be had at their GitHub page. It is still being actively maintained. There appear to be a number of contributors involved in this project at different points…
Part 2 – Accessing a Resource Recap This is a continuation of the previous post that I made some time last month. You can start reading from there to get more context – https://www.joseyamut.xyz/2021/02/24/spring-oauth2-using-password-grant-type-with-additional-headers The first part dealt with getting the access token from a 3rd party token service provider using a password grant. The…
Part 1 – Getting the Access Token In this example, I am using the older Spring Security library which is: spring-security-oauth2 The JAR file can be found at Maven public repositories here. Dependency For my case, I am specifically using the release version below because I am trying to match some limitations (Such as what…
Properties written in YAML format in my opinion reads better, far better for a human, especially when an application has tons of properties in there. Well, after all YAML was designed to be a human-readable data-serialization language. Officially it complies with JSON and is a subset of the latter (depends which version though as I’ve…
The other day I was trying to assign a container of, let’s say, numbers distributed across 20 groups, to a container with a smaller size that can only hold up to 6 groups. The bigger group has values from 0 to 19. It also means that group 0 will always have zero number value, 1…
The other day, I was working on a huge JSON object that had a number of collections in it. The entire object had to be saved into a relational database, which means I was mapping out the raw JSON data to its logical representation as database tables. Though the object wasn’t that complicated, it did…
Using Repository implementation with Spring Data, one can develop applications with an underlying database rapidly in Spring Boot. The Spring Data JPA handles the abstraction of the persistence layer quite well. Many times you probably won’t need anything else beyond what it has to offer. A lot can already be done with the exposed methods…
As a back-end developer, consuming JSON objects is pretty much very common. I think it is second only to publishing data in JSON format, the other end of what is usually a 2-way street. We may have a REST API endpoint that accepts orders for an online food delivery service that takes in JSON formatted…
Going to skip right away to the juicy stuff as much as I can. I won’t discuss about what OpenShift is or what the Secrets feature does. This is only about my experience the first time I dealt with Secrets and how I used it for a Spring Boot Kafka consumer/client application. The problem I…
So I am involved in this project currently where the project architect suggested that we follow HATEOAS-driven RESTful web service. This is probably something I have read about before, but didn’t really pay much attention to, or I simply forgot. Learning something new is always fun. Well, most of the time it is. It depends…