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A closer look at the Background Sync API

Published: June 26, 2018  •  pwa, javascript, java, spring

This blog post takes a closer look at the Background Sync API, part of the Service Worker implementation and presents an example that uses Background Sync to synchronize data between an Ionic 4 web application and a Spring Boot server application.

Check for commonly used or compromised passwords

Published: May 03, 2018  •  java, javascript

In this blog post I present four examples how you can implement password checks for commonly used or compromised passwords.

OAuth 2.0 server-to-server authorization flow between a Java application and a Google service

Published: May 01, 2018  •  java

How a Java server application can complete the server-to-server OAuth 2.0 flow and access a Google service

Searching "Have I been pwned?" passwords locally with Java

Published: March 01, 2018  •  java

In this blog post we will create Java applications that download and search the "Have I been pwned?" password list with over 501 million passwords.

Real Time Polling App with Java and JavaScript

Published: February 28, 2018  •  java, javascript

In this blog post we create a simple polling application with Java and JavaScript and send real time updates with server-sent events

Human readable regular expressions

Published: February 27, 2018  •  java, javascript

Writing human readable regular expressions with the VerbalExpression library

Access Server-sent events from Java

Published: February 26, 2018  •  java

How to consume Server-sent events in a Java application.

Working with MongoDB TTL Indexes from Java

Published: February 05, 2018  •  database, mongodb, java

A brief introduction to Time to live indexes in MongoDB and how to access them from Java

Working with MongoDB Capped Collections from Java

Published: February 04, 2018  •  Updated: February 05, 2018  •  mongodb, java, database

A brief overview of capped collections in MongoDB and how to access them from Java

Integrate Parcel into a Maven project

Published: January 13, 2018  •  Updated: January 25, 2018  •  java, javascript

An example project that integrates a front end JavaScript application with the Parcel bundler and a Spring Boot application built with Maven into one project and ultimately create one executable JAR.

Sending Web push messages from Spring Boot to Browsers

Published: January 09, 2018  •  Updated: July 18, 2018  •  java, javascript, pwa, spring

In this blog post I show you how you can send push messages from a Spring Boot application over Firebase Cloud Messaging (FCM) to connected clients with the Web Push API. The Push API is part of the Service Worker specification and does not depend on any native plugins.

Adding speech recognition to an Ionic App

Published: December 18, 2017  •  Updated: February 16, 2018  •  ionic3, javascript, java, spring

In this blog post I present three different way how to integrate a speech recognition functionality into an Ionic app. With a Cordova plugin, the Web Speech API and with RecordRTC and the Google Cloud Speech API.

Developing a self hosted location tracker

Published: November 07, 2017  •  Updated: February 16, 2018  •  ionic3, java, spring, javascript

In this blog post we create together a self hosted location tracker that consists of three parts. An Ionic/Cordova application that continuously sends the current location to a Spring Boot application from where the locations are broadcasted to a website and visualized with Google Maps.

Dynamically loading position data with Ionic and Spring Boot

Published: November 05, 2017  •  Updated: January 31, 2018  •  ionic3, java, spring, javascript

In this blog post we create an Ionic app that dynamically requests location data points from a Spring Boot server and displays them on a OpenStreetMap map. The data points are stored in a MongoDB database and we take advantage of the geospatial query support to read the data points only for a certain area.

JCE policy changes in Java SE 8u151, 8u152 and 8u162

Published: October 21, 2017  •  Updated: January 17, 2018  •  java

The latest Java update changed the way how you enable unlimited cryptography in your Java application.

Upload files from Ionic to Spring Boot with Flow.js

Published: September 26, 2017  •  java, ionic3, javascript, spring

A closer look at the Flow.js JavaScript library that helps uploading files from a browser to the server. Flow.js is a JavaScript library providing multiple simultaneous, stable, fault-tolerant and resumable/restartable file uploads via the HTML5 File API.

Spring Boot and Ionic application development with OpenAPI

Published: September 21, 2017  •  Updated: February 17, 2018  •  spring, java, javascript, ionic3

In this blog we create REST services in Spring Boot and consume them in an Ionic app. We use the OpenAPI specification for generating an API documentation and the client TypeScript code.

Pluggable file systems in Java

Published: September 17, 2017  •  Updated: February 16, 2018  •  java

How to use pluggable file systems in Java and a look at implementations outside the standard library

Do it yourself Multi Value Map with Java 8

Published: September 16, 2017  •  Updated: October 25, 2017  •  java

How to create a simple MultiValue Map with Java 8

Server-Sent Events with Spring

Published: March 05, 2017  •  Updated: February 16, 2018  •  java, spring

What are Server-Sent Events and how can you send them from a Spring Boot application

Send messages from Spring Boot to Ionic over FCM

Published: February 26, 2017  •  Updated: June 11, 2018  •  ionic3, spring, javascript, java

This post describes how a Spring Boot can send messages over FCM to an Ionic 3 app

Uploading files from Ionic 3 / Cordova to Minio / S3

Published: February 16, 2017  •  Updated: February 16, 2018  •  ionic3, cordova, spring, s3, javascript, java

How to upload files from an Ionic 3 / Cordova app directly to a Minio server or Amazon S3 with pre-signed URLs.

Upload files from Java to a Minio server

Published: February 15, 2017  •  Updated: February 16, 2018  •  java, s3

In this article we have a closer look at Minio, a self hosted S3 compatible server, and how to connect a Java application to it.

Uploading pictures from Ionic 3 to Spring Boot

Published: February 12, 2017  •  Updated: November 16, 2017  •  ionic3, cordova, spring, javascript, java

In this article we create an Ionic 3 application where the user can select a picture from the cordova camera plugin and the app uploads it to a Spring Boot server application.

JWT Authentication with Ionic 3 and Spring Boot

Published: February 05, 2017  •  ionic3, spring, java, javascript

How to implement a JWT authentication between an Ionic 3 app and a Spring Boot back end.

Form validation with Angular and Spring Boot

Published: January 26, 2017  •  Updated: November 16, 2017  •  angular, ionic3, spring, java, javascript

Example of form validation in an Ionic application. How to create custom synchronous and asynchronous validators and how to validate data on the server with the Java Bean Validation framework.

Produce RSS and Atom feeds with Springframework

Published: January 24, 2017  •  Updated: February 16, 2018  •  spring, java

How to create RSS and Atom feeds with the Spring Framework and the ROME library

Consume Protocol Buffer messages with Ionic 3

Published: January 14, 2017  •  Updated: December 23, 2017  •  ionic3, spring, java, javascript

Protocol Buffers with Spring Integration

Published: January 08, 2017  •  Updated: December 23, 2017  •  java, spring