Category Archives: Java

Spring inside Netty

http://findevelop.blogspot.ru/2014/02/netty.html Netty: делаем лёгкий сервер с блэкджеком и аннотациями Допустим вам нужно обрабатывать http-запросы в своём приложении… Пишем на servlet-ах! Spring!! ЕщёКакойТоФреймворк!!! A теперь нам нужно слушать websocket… Выбор сужается? А завтра потребуется добавить поддержку SMPP или какого-нибудь ещё “необычного” протокола? Рано или поздно вам прийдётся создать консольное java-приложение и начать изучать “встраиваемые” сервера. Встроить […]

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Java EL implicit objects

http://incepttechnologies.blogspot.ru/p/jsf-implicit-objects.html What are Expression Language Implicit Objects? JSF framework provides several objects related to current request being processed and/or execution environment. These objects aka Implicit Objects can be accessed at runtime in a facelet or backing bean using EL. Although you can access implicit objects using EL and JEE Servlet API as well, having predefined objects […]

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Mutually recuresive type variable bounds

http://stackoverflow.com/questions/23248103/example-8-1-2-1-of-java-language-specificationmutually-recursive-type-variable http://www.javaadvent.com/2013/12/type-safing-the-observer-with-mutually-recursive-bounds.html A recursive type is a type that uses itself in its definition. The simplest example is the linked list: class List<T> { T value; List<T> next; } Here, List<T> is recursively defined because it uses a List<T> in its own definition. A type variable bound (Foo in <T> extends Foo) is recursive if […]

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Apache Shiro

https://shiro.apache.org http://meri-stuff.blogspot.ru/2011/03/apache-shiro-part-1-basics.html The following is a reprint from http://meri-stuff.blogspot.ru Apache Shiro, originally called JSecurity, is Java security framework. It was accepted and became Apache top level project in 2010. It aims to be powerful and easy to be used. The project is in active development with active both users and developers mailing lists. Most important areas are […]

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Running Spring application in WebLogic

http://pauldone.blogspot.ru/2010/02/weblogic-and-spring.html   WebLogic and Spring In this blog topic I describe some of the integration points that WebLogic provides for Spring based applications. I have mixed feelings about Spring. I definitely prefer its primary focus on the Dependency Injection pattern (DI) instead of the more typical JavaEE model of using the Service Locator pattern (think […]

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JDBC url format

In case of PostgreSQL it is documented here. With JDBC, a database is represented by a URL (Uniform Resource Locator). With PostgreSQL™, this takes one of the following forms: jdbc:postgresql:database jdbc:postgresql://host/database jdbc:postgresql://host:port/database In case of MySQL it is documented here. The general format for a JDBC URL for connecting to a MySQL server is as […]

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Functional data structures In Java

Also known as purely functional data structures, these are immutable and persistent. The methods of functional data structures are referential transparent. A persistent data structure does preserve the previous version of itself when being modified and is therefore effectively immutable. Fully persistent data structures allow both updates and queries on any version. Many operations perform […]

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Cipher suites in Java SE

http://www.techstacks.com/howto/j2se5_ssl_cipher_strength.html HOWTO: Distinguish the Good SSL Ciphers from the Bad in J2SE5 One of the things I am always forgetting with SSL in Java is the relationship between the names of the ssl ciphers and whether or not any particular cipher is weak, medium, strong, etc.  The tables below have been set up to provide […]

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How to check isolation level in hibernate session

import java.sql.Connection; import java.sql.SQLException; import javax.persistence.EntityManager; import javax.persistence.FlushModeType; import javax.persistence.LockModeType; import javax.persistence.Query; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.Transaction; import org.hibernate.cfg.Configuration; import org.hibernate.cfg.Environment; import org.hibernate.jdbc.Work; import static org.junit.Assert.assertTrue; import org.junit.Test;   public class TestIsolation { @Test public void testIsolationLevel() { Connection cc = null; Session session = null; Transaction txn = null; EntityManager entityManager = entityManagerFactory.createEntityManager(); […]

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Spring contexts

Web Application context extended Application Context which is designed to work with the standard javax.servlet.ServletContext so it’s able to communicate with the container. public interface WebApplicationContext extends ApplicationContext { ServletContext getServletContext(); } Beans, instantiated in WebApplicationContext will also be able to use ServletContext if they implement ServletContextAware interface package org.springframework.web.context; public interface ServletContextAware extends Aware […]

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Basic map-filter-reduce pattern

??? JDK 7 way public interface Mapper<T, V> { public V map(T t) ; } public interface Predicate<T> { public boolean filter(T t) ; } public interface Reducer<T> { public T reduce(T t1, T t2) ; } List<Person> persons = … ; int sum = persons.map( new Mapper<Person, Integer>() { public Integer map(Person p) { […]

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Batching in Hibernate

https://docs.jboss.org/hibernate/orm/3.3/reference/en/html/batch.html https://abramsm.wordpress.com/2008/04/23/hibernate-batch-processing-why-you-may-not-be-using-it-even-if-you-think-you-are/   Most people who use batch probably find out about it by trying to perform a large operation and finding out the hard way why batching is needed. They run out of memory. Once this is resolved they assume that batching is working properly. The problem is that even if you are flushing […]

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Logging adapter for WebLogic

https://docs.oracle.com/cd/E23943_01/web.1111/e13739/logging_services.htm#WLLOG199 To redirect messages from JDK logging system to WebLogic standard log files we need to add special ServletLoggingHandler. logging.properties: # Specify the handlers to create in the root logger handlers = weblogic.logging.ServerLoggingHandler # Register handlers for the com.foo.toyshop and its child loggers com.foo.toyshop.handlers = java.util.logging.ConsoleHandler, weblogic.logging.ServerLoggingHandler # Do not send the toyshop log messages […]

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Java Unsafe

http://mishadoff.com/blog/java-magic-part-4-sun-dot-misc-dot-unsafe/   Java Magic. Part 4: sun.misc.Unsafe Java is a safe programming language and prevents programmer from doing a lot of stupid mistakes, most of which based on memory management. But, there is a way to do such mistakes intentionally, using Unsafe class. This article is a quick overview of sun.misc.Unsafe public API and few […]

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Mondrian and Pivot4J

http://www.drdobbs.com/database/olap4j-online-analytical-processing-for/230800051https://github.com/OSBI/saiku/blob/master/saiku-core/saiku-olap-util/src/main/java/mondrian/olap4j/SaikuMondrianHelper.java

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JPivot analogs

Webpivotable costs not much, works fine, but their design may be better, but thats just for me. Here their demo. icCube – nice team, support, tool totally for OLAP and their webreporting tool is enough for some usual needs, but not more. Regarding futher detailisation, this is not for you. Flexmonster – looks nice, works […]

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Configuring maven

On Windows 7 one may get the following error message: caught when connecting to the target host: Permission denied: connect to fix the problem set “MAVEN_OPTS=-Djava.net.preferIPv4Stack=true” \ in mvn.cmd

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