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Java Technologies such as J2EE, JEE,…

Using System properties in Grails

Retrieving a few of system variables is inevitable in developing computer applications within any environment. In this post, we would show you system variables existing once the application is loaded and how to retrieve a specific variable to pass it ...

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Online learning resources and tutorials for Grails learners

Since joining in EMBL-EBI as a software engineer, I have been worked with Grails for two years and a half in all my passion for this amazing framework. There has been a boring issue is that Grails official documentation and hands-on ...

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How to add a manifest file to jar file

JAR files support a wide range of functionality, including electronic signing, version control, package sealing, and others. What gives a JAR file this versatility? The answer is the JAR file's manifest. The manifest is a special file that can contain information about the files packaged in a JAR file. By tailoring this "meta" information that the manifest contains, you enable the JAR file to serve a variety of purposes. This post will explain the contents of the manifest file and show you how to work with it, with examples for the basic features:

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Combine two lists in Groovy

Combination or concatenation of two or multiple lists are believed to appear quite frequently in programming. This article aims to show you how to union two lists in Groovy in different ways. Combine lists with addAll The [crayon-5bcc011743af1481046112-i/]  method appends all ...

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Java Books and References

This text will introduce useful learning resources for someones who want to learn Java programming language. Because resources are continuously updated, this writing is too keep up. Official Java Documentation Oracle, the company owning Java, provides qualified Java Tutorials. The ...

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HashMap class in Java

The Map Hierarchy

This text aims to introduce HashMap and how to use it in Java programs. In the series of Map involved articles, HaspMap is implemented from Map interface and inherited from AbstractMap class (as shown in Fig. 1). HashMap works on ...

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Simple steps to log messages in Java programs using Log4j

This article explains a bit of the importance of application logging and log4j API in Java. The following paragraphs will give you an overview of how logging mechanism works in Java application and how use one of the common logging ...

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Unveil magic of hibernate lazy loading

SQL logging in hibernate

Recently we have discussed about the performance of retrieving collections/relations/associations inside objects. By the way, we also review the machinery that hibernate handles these relational concepts to improve the effectiveness of database operations. One of the techniques being implemented in ...

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How to create an Executable Jar File

How to create an executable jar file

In Java programming, it is common to combine several classes in one .jar (“java archive”) file.  Library classes are released in this fashion which these classes are packed into a single jar file so that it can be used flexible ...

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How to run JAR packaged applications

A few questions can be questioned when someone wants to learn Java programming. For example, how is its independent on working environment? How can we create a standalone program? How to run a Java program? etc. This post will answer ...

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