we are using the Jboss fuse 6.2 along with technical stack blueprint,camel ,activeMQ and Mybatis.
We need to know about how to configure the property files in OSGI ,
as per my knowledge we could configure .cfg files, but is there any simplest way to use like spring configuring the configuring.
In Our code we are reading from property files . using namespace ext:proeprtyplaceHolder giving that bean id and values we are giving .
Help to provide is there any simplest way to read the property files
There is several ways to add configuration, because OSGi services can access configuration via ConfigurationAdmin service. The blueprint also can access property values over it.
JBoss fuse using karaf, so you can use the following methods.
(There is some quotes from http://www.liquid-reality.de/display/liquid/2011/09/23/Karaf+Tutorial+Part+2+-+Using+the+Configuration+Admin+Service)
Configuration with Blueprint
The integration with our bean class is mostly a simple bean definition where we define the title property and assign the placeholder which will be resolved using the config admin service. The only special thing is the init-method. This is used to give us the chance to react after all changes were made like in the pure OSGi example.
For blueprint we do not need any maven dependencies as our Java Code is a pure Java bean. The blueprint context is simply activated by putting it in the OSGI-INF/blueprint directory and by having the blueprint extender loaded. As blueprint is always loaded in Karaf we do not need anything else.
<cm:property-placeholder persistent-id="ConfigApp" update-strategy="reload" >
<cm:default-properties>
<cm:property name="title" value="Default Title"/>
</cm:default-properties>
</cm:property-placeholder>
<bean id="myApp" init-method="refresh">
<property name="title" value="${title}"></property>
</bean>
After you can put a cfg file (which is a standard java property file) to
karaf's etc or deploy directory with the name of of the given persistent-id which is MyApp in our example. (For example: /etc/ConfigApp.cfg)
title=Configured title
I need to change the value of the project stage dynamically ( at runtime ), based on the environment, using JNDI. From what I understand, the JNDI will override what is defined in web.xml. Is there a document / link that will help me with how I should code it? I am using websphere 8.5
In some examples I have seen that it is defined as resource-ref, but I am not sure I understand how is that used with JNDI to make it work and change the value at runtime.
Can someone help me with this?
As JSF 2.0 spec states, you can override context parameter javax.faces.PROJECT_STAGE via JNDI entry, which is looked via reference java:comp/env/jsf/ProjectStage.
To override the context parameter, you need to define following resource environment reference in your web.xml file:
<resource-env-ref>
<description />
<resource-env-ref-name>jsf/ProjectStage</resource-env-ref-name>
<resource-env-ref-type>java.lang.String</resource-env-ref-type>
</resource-env-ref>
in the application server configuration, you can define your ProjectStage value via Namespace binding ( in the web admin console select Environment > Name Space Bindings, define new String variable with jndi name jsf/ProjectStage and value Development or Production, depending on the environment).
Finally you need to bind your reference in the project with variable in JNDI. You can do it it 2 ways, via ibm-web-bnd.xml file, defining:
<resource-ref name="jsf/ProjectStage" binding-name="jsf/ProjectStage" />
Or during application installation, in the step were you provide mappings for Resource environment references.
For detailed discussion on this topic check Dynamically change project stage value at runtime using JNDI
I have a project that I am deploying to CloudBees and I have defined some param-names inside my cloudbees-web.xml file. I would like to access these from my java application but have tried System.getProperty(),(String)env.lookup("email.user.name") all with no luck.
How can I access these from within Java?
Below is my cloudbees-web.xml file which is located under WEB-INF:
<?xml version="1.0"?>
<cloudbees-web-app xmlns="http://www.cloudbees.com/xml/webapp/1">
<!-- Changed for Privacy -->
<appid>CB_ACCOUNT/APPNAME</appid>
<!-- Extra context parameters -->
<context-param>
<param-name>email.user.name</param-name>
<param-value>test#gmail.com</param-value>
</context-param>
</cloudbees-web-app>
You can access those context parameters just like you can access any context parameter defined in your WEB-INF/web.xml, in other words:
getServletContext().getInitParameter("email.user.name")
Note that you need to be in a class instance that has access to the ServletContext, or else you need to pass the ServletContext from a class that has access to it.
Typically you will have requests served by a Servlet or JSP page... or the framework you are using will provide a means to access the context (e.g. Java Server Faces provides the external context concept - which is either a ServletContext or a PortletContext because JSF supports both containers) so in those cases it is just a question of accessing the parameter from your servlet.
If you are starting background threads to do work (which is strictly against the Servlet specification... or at least out of scope) you should be starting (and stopping - don't forget to stop them) those threads via a ServletContextListener... which also is fed the ServletContext... if you are a bold person and starting background threads from class static initializers... well your only solution is to have a ServletContextListener pull the config and hand it over to the background thread... at which point you are better off starting the tread from the ServletContextListener (also solves the loading multiple contexts from the same .war file issue... not that you'll have that on RUN#cloud)
This question is now up for Bounty! First answer that solves this problem wins.
So I've recently discovered that bundles in OSGI are not 100% isolated from each other, especially when your bundles share a common bundle that has a singleton in it, which can result in two unrelated bundles overwritting the singleton. This issue has manifested itself with the CXF libraries. Let me give a detailed example of what is happening:
We have bundle A, B and the shared bundle CXF all in a FuseESB ServiceMix (An osgi platform). CXF's Bus class is a singleton and because of how OSGI has a single classloader per bundle it will share this singleton with every other bundle that uses CXF. So I seem to be unable to create different buses for bundle A and bundle B, which is important that I do because bundle A should be using SSL and bundle B should not be using SSL. This is even more frustrating given that bundle A and bundle B have nothing to do with each other at all other than that they must be deployed together on the same ServiceMix.
Now I've been at this problem for a while now (1-2 months) and I've read up a lot of different solutions. The problem however is that a lot of the solutions require me to have complete control over the source code and in this case I do not. Bundle A that I'm creating is using some proprietary third-party non-osgi library, called Xenara, which uses CXF. For business reasons beyond my control I MUST use this third-party library. Fortunately I do have access to the CXF spring bean file that this library uses.
My guess for solving this problem is that I need to some how make it so that bundle A can use its own personal instance of CXF or at least make it instantiate its CXF Bus that isn't shared with other bundles. Here are the methods I've tried or considered:
I embedded CXF into bundle A but unfortunately the classloader kept fetching CXF from outside of bundle A instead of looking on the classpath. Never figured out how to force it to search for CXF in bundle A first before searching outside of bundle A.
Suggestions were made to make bundle A into a service. I think there were some misunderstandings and people thought that the singleton was in A and not in CXF. Regardless I tried it and it didn't solve the problem. The CXF bus was still shared between bundle A and B.
Override the classloading so that bundle A uses a different classloader for loading the CXF classes. I don't fully understand the logic for this but I'm sure it will be very tricky given that a spring bean is being used to create the CXF bus and http-conduit. See (4) below to get a better idea.
In CXF there is a way to set the CXF bus and http-conduit for a given thread context. I really want to use this solution, but I can't figure out how to translate the CXF bean file into equivalent java code. The CXF spring bean file is provided below. Note I don't have access to the source code using this http-conduit, which is why I haven't used examples show in this link here at "Using Java Code" because I don't have access to the SOAPService, the wsdl, etc...
<bean class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="systemPropertiesModeName" value="SYSTEM_PROPERTIES_MODE_OVERRIDE" />
<property name="searchSystemEnvironment" value="true" />
<property name="ignoreUnresolvablePlaceholders" value="true" />
</bean>
<cxf:bus>
<cxf:outInterceptors>
<bean class="com.xenara.messaging.security.IdentityAssertingOutInterceptor"
scope="singleton" />
</cxf:outInterceptors>
<cxf:features>
<wsa:addressing xmlns:wsa="http://cxf.apache.org/ws/addressing"/>
</cxf:features>
</cxf:bus>
<http-conf:conduit name="*.http-conduit">
<http-conf:client AllowChunking="false" Connection="Keep-Alive" />
<http-conf:tlsClientParameters disableCNCheck="true" secureSocketProtocol="TLS">
<sec:keyManagers keyPassword="${javax.net.ssl.keyStorePassword}">
<sec:keyStore type="JKS" password="${javax.net.ssl.keyStorePassword}"
file="${javax.net.ssl.keyStore}" />
</sec:keyManagers>
<sec:trustManagers>
<sec:keyStore type="JKS" password="${javax.net.ssl.trustStorePassword}" file="${javax.net.ssl.trustStore}" />
</sec:trustManagers>
<sec:cipherSuitesFilter>
<sec:include>SSL_RSA_WITH_3DES_EDE_CBC_SHA</sec:include>
...
</sec:cipherSuitesFilter>
</http-conf:tlsClientParameters>
</http-conf:conduit>
This sounds like the basic premisse of OSGi to me: isolation is provided, but you can do a lot of what you can in regular OSGi; such as, modify static members of a class, and since you all share that class (A presumably exports it, B and C import it), others will notice.
In most situations, I would advise you to not use static class state, since it is bound to mess something up for other bundles.
In your situation, it seems to me that bundle A is a library that has no real use being shared in the framework. I would package the library inside both of the using bundles, if you need real isolation, and not worry about the overhead too much.
For the record: this situation has nothing to do with Servicemix, it's basic Java: if we're talking about the same class, and someone changes a static property, others will notice. If this situation confuses you, you could read up a bit about the class loading and sharing mechanisms in OSGi.
The problem you are facing is fairly essential and basic. You have a static state in a supporting library CXF, while you still want shared instances of the libraries using CXF. You cannot modify the shared libraries (due to the sheer size), nor can you modify CXF (closed-source?). Let's call these shared libraries Foo and Bar.
Suppose you have the following classes:
CXF#1
Foo#1, using CXF#1
Bar#1, using CXF#1
WebApp#1, using Foo#1 and Bar#1
If I understand correctly, you now want another application to use the same instances of Foo and Bar, without using the same underlying library CXF#1. This amounts to the following situation.
CXF#2
CXF#1
Foo#1, using CXF#1 when called by App#1, using CXF#2 when called by App#2
Bar#1, using CXF#1 when called by App#1, using CXF#2 when called by App#2
WebApp#1, using Foo#1 and Bar#1
WebApp#2, using Foo#1 and Bar#1
This is just not possible; not in OSGi and not in any Java framework. An existing class cannot dynamically bind to another class, making the choice based on the calling Bundle. The only way to do this without modifying the libraries, is to duplicate the supporting libraries:
CXF#2
CXF#1
Foo#1, using CXF#1
Bar#1, using CXF#1
Foo#2, using CXF#2
Bar#2, using CXF#2
WebApp#1, using Foo#1 and Bar#1
WebApp#2, using Foo#2 and Bar#2
Indeed, this is a lot of effort and will explode the number of packages on disk and in memory. If the CXF package can only be used by a single application, the most logical solution is to duplicate the package and embed it everywhere you use it. Yes, this includes any and all libraries the package depends on.
A hacky/risky way to resolve this is as follows. You should be able to decompile the CXF class. This will allow you to modify the class as follows:
class CXF {
[...]
public static CXF getInstance() {
// based on the current Stack frame, determine which instance to return. Remember, the instance should be based on the WebApp bundle (while you still have shared libraries in between!)
}
}
This is not foolproof. Suppose your WebApp starts a callback thread originating from library A. This thread calls CXF.getInstance() -> The getInstance() method has no way of determining which WebApp started the callback thread.
The correct solution is to modify all libraries not to use the Singleton pattern. You can probably hack your way around the problem by implementing a special classloader, but this opens a whole other can of worms.
-- EDIT --
After reading up on CXF, it seems very strange that CXF exposes a Singleton class. The thing is made for OSGi! You are probably better off asking the question on the CXF mailing list; they will know all of the special sugar and reasons for making a singleton instance, and probably already thought about this usecase.
It's clear to me how to inject an object which is in my domain (I have access to the source) using Weld. You just annotate the implementation with e.g. #Named and #ApplicationScoped, and then annotate the target attribute with #Inject to get the implementation injected.
However, not sure how can I inject implementations of classes which I don't have access to its source code. For example, I am using Dozer. Dozer mapper is programmed against an interface (Mapper) and I want Weld to inject the implementation (DozerBeanMapper), but since I don't have access to the source cause I am using a .jar dependency, I cannot annotate it.
Any ideas on how to achieve this?
Annotations embedded within POJOs is the internal configuration. Internal configuration and 3rd party components don't mix. External configuration(such as beans.xml) is the only way. You should check the document of Weld for external configuration.