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Getting Started with jOOQ, H2, and Maven


This article is part of our Academy Course titled jOOQ – Type safe DB querying. jOOQ is a good choice in a Java application where SQL and the specific relational database are important. It is an alternative when JPA / Hibernate abstract too much, JDBC too little. It shows, how a modern domain-specific language can greatly increase developer productivity, internalising ...

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An introduction to optimising a hashing strategy


Overview The strategy that’s used for hashing keys, can have a direct impact on the performance of a hashed collections such as a HashMap or HashSet. The built-in hashing functions are designed to be generic and work well in a wide range of use cases. Can we do better, especially if you have a good idea of the use case? ...

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New in JMS 2.0


This post lists ALL of the new APIs (interfaces/classes/annotations etc.) introduced in JMS 2.0 (part of the Java EE 7 platform). These have been categorized as follows API simplification Ease of use Exception Handling Miscellaneous Here is a quick summary along with some code snippets API simplification JMSContext Simpler abstraction on top of Connection and Session objects which eliminates the ...

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Custom User types in GORM


Recently, I wanted to model a Merchant which like many things in a domain model had an Address. I thought it made sense that the Address was embedded inside the Merchant. Reasons: It had no lifecycle outside the Merchant. Merchant dies so should the address. It only ever belonged to one and only one Merchant So pretty obvious this was ...

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Question for self-organizing teams


Try this thought experiment. You are a software development manager. You learn about agile and you think it is good. You adopt agile and you make all your teams into self-organizing teams. (Leave aside the question of whether you then quit in a fit of “no managers needed” – we can talk about that later.) Most of your teams work ...

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7 Java Performance Metrics to Watch After a Major Release


The Java performance metrics you need to follow for understanding how your application behaves in production Unlike the days when software used to be shipped in boxes and there was no way of knowing how it will perform in production, today almost any metric you can think of can be tracked down and reported. The problems we’re now dealing with ...

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JAR Manifest Class-Path is Not for Java Application Launcher Only


I’ve known almost since I started learning about Java that the Class-Path header field in a Manifest file specifies the relative runtime classpath for executable JARs (JARs with application starting point specified by another manifest called Main-Class). A colleague recently ran into an issue that surprised me because it proved that a JAR file’s Manifest’s Class-Path entry also influences the ...

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Chronicle Journal – Customizable Data Store


Overview The way to make any data structure or algorithm as fast as possible is for the code to do exactly what you want and no more. The problem with building a data store which does every thing anyone could want is that it won’t do anything particularly well. What can you achieve with a custom data store in terms ...

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Passing Arrays to a PostgreSQL PL/pgSQL Function


It can be handy to pass a collection of strings to a PL/pgSQL stored function via a PostgreSQL array. This is generally a very easy thing to accomplish, but this post demonstrates a couple of nuances to be aware of when passing an array to a PL/pgSQL function from JDBC or psql. The next code listing is for a contrived ...

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FREE RescueTime Annual Subscription Giveaway from Java Code Geeks and RescueTime!


Feeling your productivity is plummeting with all the distractions of modern digital life? Struggling to find your ideal work‑life balance? Then we have something especially for you! We are running a contest giving away a FREE annual subscription for the kick-ass RescueTime app. RescueTime helps you understand your daily habits so you can focus and be more productive. It runs ...

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