How to use React from the browser

React, as you probably know having reached this page, is a visualization framework created by Facebook. This small guide explains how to use react from the browser without any additional tool. Professional development with React nowadays includes the usage of npm (node package manager) to install packages like React and ReactDOM, and that of module bundlers … Continue reading “How to use React from the browser”

Iniziare con React: come usare React dal browser

React, come probabilmente saprete se siete giunti qui, è il framework per la visualizzazione creato da Facebook. Questa piccola guida spiega come utilizzare React dal browser senza l’uso di altri tool. Lo sviluppo professionale con React oggi come oggi prevede infatti l’uso di npm (node package manager) per l’installazione dei pacchetti come React e ReactDOM, … Continue reading “Iniziare con React: come usare React dal browser”

Canvas o SVG, come scegliere

Canvas ed SVG sono due tecnologie per il disegno disponibili all’interno di HTML 5.  Come scegliere quale utilizzare? Meglio Canvas o SVG? C’è chi usa sempre l’uno o sempre l’altro, ma la scelta non è così semplice. Bisogna capire le caratteristiche dell’uno e dell’altro prima di decidere. Vediamo prima un po’ di storia, per capire … Continue reading “Canvas o SVG, come scegliere”

javax.net.ssl.SSLHandshakeException: “Remote host closed connection during handshake” opening an HTTPS page with HTMLUnit

While trying to fetch the HTTPS page https://portal.mvp.bafin.de/database/AnteileInfo/ using HTML Unit 2.23 under Java 7, Ubuntu Linux, I received the following exception: Remote host closed connection during handshake

The code was the following

  The problem was solved upgrading to Java 8. I upgraded to Java 8 after reading Oracle’s blog about HTTPS … Continue reading “javax.net.ssl.SSLHandshakeException: “Remote host closed connection during handshake” opening an HTTPS page with HTMLUnit”

Hibernate/c3p0: apparent deadlock

The apparent deadlock message issued by c3p0, a connection pool manager of Hibernate, can sometimes be misleading. Most of the times, it is caused by connection errors. So, check your firewall, and, for Postgresql  try the following command from the command line

If this works, you should have no problem connecting to Postgresql. The … Continue reading “Hibernate/c3p0: apparent deadlock”

Create a production build using React JS

You probably saw some warnings that say you’re using React in development mode, and want to know how to create a production build using React. Why you get a warning of being in React development mode Normally you import React JS in your javascript ECMA 6 code with the following statements in a .js file … Continue reading “Create a production build using React JS”

How to downgrade from React JS 16 to 15

If you, as me, upgraded React 15 to 16, and then noticed a bug in you app, you’d like to downgrade, at least temporarily, to React 15. To do this, you need to issue the following command:

This will bring React to version 15.6.2 again. After fixing the bug, you can run the following … Continue reading “How to downgrade from React JS 16 to 15”