Category Archives: Programming

How to get a job with 70 lines of code

After my recent post How to get a job with 250 lines of code there is a new challenge available, cf. followthewhiterabbit: They kindly provide a list of words containing the building blocks of the solution as well as an “anagram … Continue reading

Posted in Hash functions, Programming | Tagged , , , , , | 3 Comments

Java bean differences

From time to time your application needs to work on certain data objects or entities. Depending on the situation and the complexity, you want to have logging that will help analyzing what the application was doing during a past time … Continue reading

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Apache commons-collections vulnerability – try it at home

The commons-collections certainly belong to the most popular java libraries out there and are used by many projects and people, including me. In my opinion it is beautiful library, has a nice API, fantastic test coverage etc. In many situations … Continue reading

Posted in Programming, Security, Security/Encryption | Tagged , , , | 2 Comments

Mocking Spring Data repositories

Unit testing should be a substantial part of the work of any developer. If you are using Spring Data, maybe in conjunction with Spring Boot, the time it takes to boot up a test environment can be quite substantial. For … Continue reading

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TLS/SSL certificate exchange in Java

In today’s blog post, we will take a look on how to handle (somewhat self-signed) certificates in Java. 1. Example server using spring-boot Let’s set up a minimal spring-boot RESTful service. Basically a ‘Hello world’-type one. Nothing fancy, just for … Continue reading

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How to get a job with 250 lines of code

Recently, I stumbled upon a cryptographic challenge posed by a company called “Trustpilot”. The problem was available at http://followthewhiterabbit.trustpilot.com/challenge2.html. For completeness I post a screenshot here: Let that sink for a little while. Generously, the key has only six unknowns, … Continue reading

Posted in Encryption, Programming, Security/Encryption | Tagged , , , , , | 1 Comment

Random Java objects for testing

As a Java developer you should test the code you’re writing. In a perfect world every line of code should be covered by a test scenario. But writing tests takes time and doesn’t add functionality to your product. To make … Continue reading

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