Java: Find all instances of System.out.println()

A good Java application should print only the absolute necessary to standard out. Not to do so can mean a serious hit in performance and can make it difficult to debug issues. Unfortunately either we ourselves or our colleagues put System.out.println() statements in the code and then forget to remove them. Here are two solutions how … Continue reading Java: Find all instances of System.out.println()

Generate md5 Hash for Maven

Maven creates and checks MD5 checksums at various times. For instance, when downloading an artifact from a repository, Maven checks whether the checksum of the downloaded files (e.g. POM, JAR) is correct. I am uploading Maven artifacts manually to a very simple, file-based repository. This requires me to calculate the Maven checksum for artifacts manually. What sounds … Continue reading Generate md5 Hash for Maven

Understanding Creation of GWT Serialization Policy Files (.gwt.rpc)

Today I deep-dived a bit into how GWT creates and reads Serialization Policy files. These are the .gwt.rpc files which are generated beside the JavaScript files for GWT modules. Chiefly, I learned two things: The .gwt.rpc files are only used by the server. The client never reads them. The .gwt.rpc files are generated in the … Continue reading Understanding Creation of GWT Serialization Policy Files (.gwt.rpc)

Sandboxing JavaScript in Java App – Link Collection

The JVM is by design an insecure environment and it is generally difficult to run untrusted code in a sandboxed environment. However, it seems that is relatively easy to sandbox JavaScript code running in Oracle Nashorn. The instructions are here. Strangely, this was not easy to find through a Google search. Below I have listed … Continue reading Sandboxing JavaScript in Java App – Link Collection

Using RapidSSL Certificate from GoGetSSL for Java Server

IMPORTANT: I found it a lot easier and less error prone to use the GUI tool Portecle to go about generating a SSL certificate/key. You can find my instructions to do so in another post. The following steps show how a RapidSSL certificate obtained through GoGetSSL can be used to secure a Java server. Step … Continue reading Using RapidSSL Certificate from GoGetSSL for Java Server

Xtend Error: Cannot find class Consumer

Problem When deploying you Xtend application to a different environment than your development environment you might encounter an error such as: [ERROR] symbol: class Consumer [...] [ERROR] cannot find symbol Solution This error is caused by Xtend trying to use Java 8 features. It does so when your development machine runs Java 8. For eclipse, … Continue reading Xtend Error: Cannot find class Consumer