Ivan Lagunov's Blog

This is a short "recipe" article explaining how to configure basic authentication for the following setup: Apache Tomcat with some application that need be partially password-protected Apache HTTP Server 2.4 as a proxy CentOS 7 Linux server Although basic authentication can be configured within Tomcat itself, my target is to use Apache for that purpose. In addition, as passing unencrypted credentials over the web is insecure, I'm going to install SSL certificates to enable HTTPS for the part of my application. This setup can be used when a part of an internal application need be secured to make it publicly accessible using a separate firewall/proxy (out of scope of this article), that part will be password-protected and SSL-encrypted. Steps Copy certificates into /etc/ssl/certs/ivanlagunov.com Create symlink: cd /etc/httpd sudo ln -s /etc/ssl/certs/ivanlagunov.com Install Apache mod_ssl sudo yum -y install mod_ssl Create file with user credentials for basi...

Here I'll show an example of using Oracle Data Pump Import (impdp) utility. It allows importing Oracle data dumps. Specifically, below is the list of steps I used on an existing Oracle schema to reload the data from a dump. Steps to reload the data from an Oracle dump We start with logging into SQL Plus as sysdba to be able to manage users. sqlplus sys/password@test as sysdba Dropping the existing user. CASCADE clause will ensure that all schema objects are removed before the user. SQL> DROP USER test CASCADE; Creating a fresh user will automatically create an empty schema with the same name. SQL> CREATE USER test IDENTIFIED BY "testpassword"; Granting DBA role to the user to load the dump later. Actually, it's an overkill and loading the dump can be permitted using a more granular role IMP_FULL_DATABASE . SQL> GRANT DBA TO test; Registering the directory where the dump is located. SQL> CREATE DIRECTORY dump_dir AS '/home/test/dumpd...

Here you'll find a short overview of the actions required for publishing your artifacts to Maven Central Repository . The best way to publish your artifacts is using Open Source Software Repository Hosting (OSSRH) which runs Sonatype Nexus Platform . We'll follow the official guide with some remarks. Get permission for deployment. Deployment of artifacts. Release procedure. Get permission for deployment In the beginning you need to get permission for deployment under a certain Maven groupId. This should be done by signing up and creating a ticket in Sonatype JIRA . If the groupId already exists, either the initial requester should apply for a new user account or you should demonstrate an approval from the project owners. As a result, you'll get an account in OSSRH . For example, this is how I requested permission for com.github.dita-ot groupId. Deployment of artifacts The deployment is the first phase of artifacts publication. Here you need to create and s...

In this article I'm going to review Java 8 Lambdas use cases after I've watched the Lambdas have come to Java! screencast from Typesafe. As a nice example, I've decided to count comparisons in the Quicksort algorithm. Basic algorithm. Inline lambdas. Method references. Basic algorithm Here is a basic implementation where we count comparisons in the Quicksort algorithm: public class QuickSort { public static long countComparisons(List<Integer> a) { if (a.size() <= 1) return 0; int p = getPivot(a); int i = 1; for (int j = 1; j < a.size(); j++) { if (a.get(j) < p) { if (j > i) swapInList(a, i, j); i++; } } swapInList(a, 0, i - 1); return countComparisons(a.subList(0, i - 1)) + countComparisons(a.subList(i, a.size())) + a.size() - 1; } private static Integer getPivot(List<Integer> a) { return...

This article will guide you through the steps showing how to use the Authentication Framework in a Cocoon 2.2 application. Maven dependencies. Spring configuration. Sitemap. Login page and controls. Maven dependencies You need the following dependency in your pom.xml : <dependency> <groupId>org.apache.cocoon</groupId> <artifactId>cocoon-auth-impl</artifactId> <version>1.0.0</version> </dependency> Spring configuration Authentication Framework has a flexible configuration based on a concepts of applications and security handlers . There can be several applications defined and running at the same that are simply independent security zones of your web application. The security details of an application are specified using a security handler. There are several implementations provided and you're free to implement your own. Here is the SimpleSecurityHandler used that takes the hardcoded credentials: <?xml versio...

This article is devoted to an upgrade of a common JSF Spring application. Time flies and there is already Java EE 7 platform out and widely used. It's sometimes said that Spring framework has become legacy with appearance of Java EE 6. But it's out of scope of this post. Here I'm going to provide notes about the minimal changes that I found required for the upgrade of the application from JSF 1.2 to 2.1, from JSTL 1.1.2 to 1.2, from Servlet 2.4 to 3.0, from Spring 3.1.3 to 4.0.5, from RichFaces 3.3.3 to 4.3.7. It must be mentioned that the latest final RichFaces release 4.3.7 depends on JSF 2.1, JSTL 1.2 and Servlet 3.0.1 that dictated those versions. This post should not be considered as comprehensive but rather showing how I did the upgrade. See the links for more details. Jetty & Tomcat. JSTL. JSF & Facelets. Servlet. Spring framework. RichFaces. Jetty & Tomcat First, I upgraded the application to run with the latest servlet container versio...

Quite a while ago I had users complaining they could not use my application from another secure network zone. It appeared the root cause was in using Yahoo CDN for serving YUI resources while there was no internet access in that specific network zone. Also living behind a proxy, our regular users used to suffer from longer delays from time to time due to proxying. An obvious solution turned out to be using a locally served YUI. For this a combo loader is required if you care about efficiency on Production. Installation To start with, there are several alternative open-source tools that can be used for combo loading: Official PHP loader by Yahoo – is obsolete and is said not to work with any version over 3.3.0. CGI script combo – I cannot say much about it besides that it's 3 years old. Node.js combo handler – is kept updated and is the one that I decided to use. The Node.js combo handler is supplied with rather self-contained README file at github. Nevertheless, I...