The problem I’ve been address in my most recent work block has been to develop an interface to a relational data store which can be used either as a local DB, or via webservices. The concept is quite straight forward, we want CRUD operations on a set of data objects. The schema is fairly straight forward too, with a core hierarchy of elements with a few enumerated lists. As well as a few cuts across the hierarchy. ...
Recently I had need to deploy some Spring webapps which required predeploy configuration. Being the first time I had to find a serious answer I looked to the mythical JNDI for an answer. This document is meant to complement other Spring JNDI documents out there. Essentially the problem is this. We need to deploy a webapp. The webapp needs configurations (database and webservice endpoint locations). Editing properties files or XML config within the webapp isn’t nice, because on a redeploy the config will be lost. Inside containers like Tomcat I am not aware of a way to easily add extra items to the classpath which won’t get nuked unexpectedly, so solutions like PropertyPlaceholderConfigurer don’t really fly as the properties file will end up within the webapp. And I don’t like the idea of setting environment variables for to locate such things. ...
Here’s a very weird Maven/Java issue. The error message (below) occurs in my build phase where JaxB is called to produce some Java objects from XML. JaxB calls HyperJaxB, and on some systems it crashes. [ERROR] XJC while compiling schema(s): org.apache.commons.logging.LogConfigurationException: org.apache.commons.logging.LogConfigurationException: org.apache.commons.logging.LogConfigurationException: Class org.apache.commons.logging.impl.Log4JLogger does not implement Log Caused by: org.apache.commons.logging.LogConfigurationException: org.apache.commons.logging.LogConfigurationException: org.apache.commons.logging.LogConfigurationException: Class org.apache.commons.logging.impl.Log4JLogger does not implement Log Caused by: org.apache.commons.logging.LogConfigurationException: org.apache.commons.logging.LogConfigurationException: Class org.apache.commons.logging.impl.Log4JLogger does not implement Log Caused by: org.apache.commons.logging.LogConfigurationException: Class org.apache.commons.logging.impl.Log4JLogger does not implement Log ...
In this example an InvestigationType has many SampleType’s. If I load an InvestigationType via em (entity manager) find it also loads the samples. InvestigationType inv2 = (InvestigationType) em.find( InvestigationType.class, inv.getId()); System.out.println(“Inv2 ID="+inv2.getId()); System.out.println(“Inv2 Title="+inv2.getTitle()); assertTrue(inv2.getSample().size() == 2); However, if I load a SampleType the investigation field is null, unless I refresh the object. // Get a sample SampleType s3 = (SampleType) em.find( SampleType.class, inv2.getSample().get(0).getId()); em.refresh(s3); System.out.println(convertDataToXmlString(s3)); InvestigationType inv3 = s3.getInvestigation(); assertNotNull(inv3); From my understanding I should not have to do this as the fetching should be the same in both instances, ie resolving the parent by default. Similarly, if I query for both objects the references are correctly loaded. ...
Slashdot | Is Apple Killing Linux on the Desktop? This is a summary of my experiences walking the path between Linux (Ubuntu/Gnome) and OSX. For background I’ve been using Linux on the desktop for about 7 years, and only in the past 2 months have purchased a MacBook. For years I’ve been using linux on the desktop, first Debian/Gnome and more recently Ubuntu/Gnome. I must say I really appreciated how well configured the Ubuntu desktop was out-of-the-box, and through good things coming together, how well the dynamic monitor configuration worked. As a programmer, web monkey, researcher and academic writer I had no complaints about the Linux desktop per se. I didn’t really miss any applications, and VM ware could certainly facilitate whatever was required. ...
The situation is this. I had a working application which used Hibernate annotated classes, and JTA for data bindings, within a spring framework. Then I moved the annotated classes into a Jar file, and the application stopped working. Hibernate knew nothing about the classes because the PersistenceAnnotationBeanPostProcessor does not traverse into the JARS on the classpath. Further neither the entity manager or HibernateJpaVendorAdapter have options to specify the explicit paths to the classes. ...
Because ACEGI depends on spring 1.2.6, we need to override a few dependencies if we want to use spring 2.0.6. To do this, we use the following exclusions:
The situation I want to deal with is this: Public Web Root |-plone \-portals |-portal1 (server A) \-portal2 (server B) In apache 2.2 they (the writers of the Apache docs) seem to prefer the use of mod_proxy_ajp, which is an AJP/1.3 driver for mod_proxy. At the apache end we just install mod_proxy_ajp and add a line such as the following to the proxy_ajp.conf file: ProxyPass /portals/portal1 ajp://nigel-dev:8009/portals/portal1 Note that the paths on the proxy host and the application server are the same. This is important, as at the application end it will only know its path name from its context, and unless you want to do some url rewriting, and possible use something called ProxyHTMLURLMap. It, like most potentially useful software, isn’t available in Red Hat, so we can’t investigate this option. ...
Some brief background. Ant is the stock standard Java build system, much as Make is for C/C++. Maven is a newer Java build system which tried to, amongst other things, solver the Jar dependency hell problem, as well as make a standard project directory layout. From the Maven guide: <groupId>log4j</groupId> <artifactId>log4j</artifactId> <version>1.2.9</version> </dependency> Now when you go to compile with maven it goes and gets all the dependencies, puts them in your local repository (~/.m2/repository) and then into your project’s build class path. This is covered in more detail at the Maven website. ...
function spawn() { NODE=$1 COUNT=$2 echo Spawning $COUNT on $NODE rsh $NODE -n “~/mark.sh” & #rsh $NODE -n “cd $PWD ; ./run.sh –agent –threads $COUNT” & } LAST= COUNT=0 for N in $NODES ; do if [ “$N” = “$LAST” ] ; then COUNT=$[COUNT+1] else if [ 0 -ne $COUNT ] ; then spawn $LAST $COUNT fi COUNT=1 LAST=$N fi done if [ 0 -ne $COUNT ] ; then spawn $LAST $COUNT fi ...