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Automatically converting password hashes in Grails spring-security-core


I was looking at this Stack Overflow question about converting password hashes and realized that it’s possible and rather convenient when using the spring-security-core plugin to automate the process. To start, we’ll need a PasswordEncoder that can work with both algorithms. Here I’m assuming that you’ll be converting from SHA-256 (optionally with a salt) to bcrypt, but the general approach ...

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Event Emitter in node.js


Event emitter from one class triggers an event to which other functions from other classes can listen. Libraries offer implementations of a framework for publishing events and listening to them. On Node many objects can emit events. The .on method in a Event Emitter – We can listen for these events by calling one of these objects “on” method, passing ...

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An Annotation Nightmare


                      @XmlElementWrapper(name="orders") @XmlJavaTypeAdapter(OrderJaxbAdapter.class) @XmlElements({ @XmlElement(name="order_2",type=Order2.class), @XmlElement(name="old_order",type=OldOrder.class) }) @JsonIgnore @JsonProperty @NotNull @ManyToMany @Fetch(FetchMode.SUBSELECT) @JoinTable( name = "customer_order", joinColumns = { @JoinColumn(name = "customer_id", referencedColumnName = "id") }, inverseJoinColumns = { @JoinColumn(name = "order_id", referencedColumnName = "id") } ) private List orders; Wait. What? Is this really what we have come to? ...

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Project Student: Persistence With Spring Data


This is part of Project Student. Other posts are Webservice Client With Jersey, Webservice Server with Jersey and Business Layer. The final layer of the RESTful webapp onion is the persistence layer. There are two philosophies for persistence layers. One camp sees the database as a simple store and wants to keep this layer extremely thin. The other camp knows ...

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Searching Subversion Logs with Groovy


There are times when I want to quickly search a Subversion repository by author, by range of revisions, and/or by commit messages. Krzysztof Kotowicz has posted the blog post Grep Subversion log messages with svn-grep that introduces svn-grep, a bash script making use of the command line XML toolkit called xmlstarlet (xmlstarlet is also available on Windows). This is a ...

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Memory leaks and memory management in Java applications


One of the more prominent features of the Java platform is its automatic memory management. Many people translate this feature erroneously into there are no memory leaks in Java. However, this is not the case and I am under the impression that modern Java frameworks and Java-based platforms, especially the Android platform, increasingly contradict this erroneous assumption. In order to ...

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Big Data and R


This blog post is a presentation of tips on computing with Big Data in R, using Revolution R Enterprise 7.0 and RevoScaleR, Revolution’s R package for HPA computing, as introduced by Revolution Analytics blog. For more detailed information you can take a look at Tips on Computing with Big Data in R. 1 Upgrade your hardware Since bigger is better, ...

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Determining Presence of Characters or Integers in String with Guava CharMatcher and Apache Commons Lang StringUtils


A recent Reddit post asked the question, “Is there a predefined method for checking if a variable value contains a particular character or integer?” That question-based title was also asked a different way, “A method or quick way for checking if a variable contains any numbers say or (‘x’,2,’B’) like a list?” I am not aware of any single method ...

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