Accessing an EJB deployed on websphere community server using Open EJB? - ejb-3.0

How can I access an EJB deployed on websphere community server using Open EJB? I'm trying to use code like the following but am not sure what to use for a URL. Note I've tried port 2809 and 1099 with ejb: and IIOP URL prefixes.
Properties props = new Properties();
props.put(Context.INITIAL_CONTEXT_FACTORY,"org.apache.openejb.client.RemoteInitialContextFactory");
props.put(Context.PROVIDER_URL,"IIOP://127.0.0.1:2809");
Context ctx = new InitialContext(props);
Object ref = ctx.lookup("CalculatorRemote ");
CalculatorImpl h = (CalculatorImpl )PortableRemoteObject.narrow(ref,CalculatorImpl.class);

Try this:
props.put(Context.PROVIDER_URL,"ejbd://127.0.0.1:4201");

Related

Unable to establish connection using jms jndi

I am very new to JMS & JNDI, and I'm trying to receive message from a queue programatically, but I am not sure how I can connect to the server. I have Websphere console UI where I login to manage all my queues. This console UI is hosted at linux-server:7276. Below is the UI link
https://my-server:9043/ibm/console
I have referred to the sample classes from IBM MQ JmsJndiConsumer:
String contextFactory = "com.sun.jndi.ldap.LdapCtxFactory";
String initialContextUrl = "ldap://my-server:9043"
Hashtable<String, String> environment = new Hashtable<String, String>();
environment.put(Context.INITIAL_CONTEXT_FACTORY, contextFactory);
environment.put(Context.PROVIDER_URL, initialContextUrl);
environment.put(Context.SECURITY_PRINCIPAL, userName);
environment.put(Context.SECURITY_CREDENTIALS, password);
InitialContext context = new InitialContext(environment);
It always throws an error in the context Connection or outbound has closed.
The queue I am trying to connect to has these details:
Connection factories : jms/atConnectionFactory
queue-manager : appit-node.Sit-TBus
Bus name : TBus
queue name : jms/appitone-event
Bootstrap Member : linux-server:7276
You're using my-server:9043 for both your HTTPS and LDAP server. Both of these can't be using the same port on the same machine so one of them must be wrong which is almost certainly why it's failing.

OpenLiberty NameNotFoundException: java:/comp/env

I have a web app running in Tomcat correctly that I want to run on the new OpenLiberty server, the app is starting correctly inside OpenLiberty but at the moment of the database connection initiation is throwing the following exception:
[Default Executor-thread-15] 2018-03-15 15:02:30 ERROR TomcatConnectionManager:41 - Loading jdbc/mysql/myaap failure
javax.naming.NameNotFoundException: java:/comp/env
at com.ibm.ws.jndi.url.contexts.javacolon.internal.JavaURLName.<init>(JavaURLName.java:83)
at com.ibm.ws.jndi.url.contexts.javacolon.internal.JavaURLNameParser.parse(JavaURLNameParser.java:39)
at com.ibm.ws.jndi.url.contexts.javacolon.internal.JavaURLNameParser.parse(JavaURLNameParser.java:60)
at com.ibm.ws.jndi.url.contexts.javacolon.internal.JavaURLContext$NameUtil.<init>(JavaURLContext.java:474)
at com.ibm.ws.jndi.url.contexts.javacolon.internal.JavaURLContext.lookup(JavaURLContext.java:321)
at com.ibm.ws.jndi.url.contexts.javacolon.internal.JavaURLContext.lookup(JavaURLContext.java:370)
at org.apache.aries.jndi.DelegateContext.lookup(DelegateContext.java:161)
The above exception is thrown during the lookup phase:
Context initContext = new InitialContext();
Context envContext = (Context) initContext.lookup("java:/comp/env");
Is there any way to make it work on OpenLiberty doing less changes possible?
On OpenLiberty the equivalent lookup would look like this:
Context initContext = new InitialContext();
Context envContext = (Context) initContext.lookup("java:comp/env");
The key is that you need to use java:comp/... instead of java:/comp/...
The reason why Tomcat is different than Liberty is because Tomcat is just a servlet container and Liberty conforms to the full Java EE specification.
According to section EE.5.2.2 of the Java EE 7 spec:
The application component’s naming environment is composed of four logical
namespaces, representing naming environments with different scopes. The four
namespaces are:
java:comp – Names in this namespace are per-component (for example, per enterprise
bean). Except for components in a web module, each component gets
its own java:comp namespace, not shared with any other component. Components
in a web module do not have their own private component namespace.
See note below.
java:module – Names in this namespace are shared by all components in a
module (for example, all enterprise beans in a single EJB module, or all components
in a web module).
java:app – Names in this namespace are shared by all components in all modules
in a single application, where “single application” means a single deployment
unit, such as a single ear file, a single module deployed standalone, etc.
For example, a war file and an EJB jar file in the same ear file would both have
access to resources in the java:app namespace.
java:global – Names in this namespace are shared by all applications deployed
in an application server instance. Note that an application server instance
may represent a single server, a cluster of servers, an administrative
domain containing many servers, or even more. The scope of an application
server instance is product-dependent, but it must be possible to deploy multiple
applications to a single application server instance.
Had a similar problem going between WebSphere and Tomcat. I'm developing and testing on a Tomcat server and using utilities I can't change that handle the DB connection to our DB2. On WebSphere it uses a constant set to "jdbc/COMPDB2" to retrieve the DataSource when I configure Tomcat and my Web.xml file it resolves to "java:comp/env/jdbc/SFCCDB2"
My work around for on local work space it to add a listener to copy the resource to the level in the InitialContext. I'm not very experienced with the server side of things but this is working so far using TomEE 7.0.81.
InitialContext ctx = new InitialContext();
DataSource ds = (DataSource) ctx.lookup("java:comp/env/jdbc/SFCCDB2");
javax.naming.Context envCtx = (javax.naming.Context) ctx.lookup("java:comp/env");
try{
/*
Added this because after redeploying code to the server it would error
connecting to the DB with an SQLException Datasource is closed
*/
DataSource dataSource = (DataSource) ctx.lookup("jdbc/COMPDB2");
ctx.destroySubcontext("jdbc");
} catch (NamingException e){
//Doesn't exist; safe to just add
}
ctx.createSubcontext("jdbc");
ctx.bind("jdbc/COMPDB2", ds);
ctx.close();

EJB3 & Websphere Application Server 7: NoClassDefFoundError on Remote EJB

I have been trying all day to connect to a Remote EJB on a Websphere Application Server 7. This configuration is necessary for project specific reasons. Its goal is to connect two applications together that are on independent EAR but on the same server.
I have been trying to access a dummy method that does not have any parameters.
The lookup URL is the one copied from the EJB deployment on my local server and it complies with EJB3.0 IBM specifications according to the information here.
I have seen several other posts on stackoverflow related to EJB Remote issues in WAS (but I cannot link all threads because of my user limitations) but they do not resolve or are not the same as my problem.
Local EJB invocation works fine.
Here is the implementation. I do not use any specific IBM WAS libraries in the imports:
The class that is connecting to the Remote EJB:
Properties env = new Properties();
env.put(Context.INITIAL_CONTEXT_FACTORY, "com.ibm.websphere.naming.WsnInitialContextFactory");
env.put(Context.PROVIDER_URL, "iiop://localhost:2809");
Context ctx = new InitialContext(env);
Object object = ctx.lookup("ejb/<component-id>#<package.qualified.interface>");
RemoteInterface interface = (RemoteInterface)javax.rmi.PortableRemoteObject.narrow(object, RemoteInterface.class);
String sResponse = (String)interface.dummy();
The definition of the remote interface is:
#Remote
public interface RemoteInterface {
public String dummy() throws Exception;
}
And my implementation is:
#Override
public String dummy() throws Exception {
return "string";
}
Environment information:
Websphere Application Server 7
JDK 1.6
EJB 3.0
EAR 5.0
Maybe someone can give me some pointers on what to do next.

how to change Java code to access database using JDBC after creating JDBC connection pool in GlassFish?

I'm new to JDBC. I've installed GlassFish 3.1.1 on Centos 6.2 and need to use it with an application that connects to an Oracle 11G database on another server. I've read through the documentation for GlassFish and think I understand how to create a JDBC connection pool as well as a JDBC resource. My question is, how do I use this information when coding the java middle-tier to connect to the database?
Currently (with just GlassFish install and no JDBC configuration), I am relying on the CentOS enviroment variables for java (such as CLASSPATH) to allow the web application to use the JDBC drivers. However, I'm getting the following error:
java.lang.NoClassDefFoundError: oracle/jdbc/pool/OracleDataSource
Thus, my attempt to create a JDBC connection pool and resource in GlassFish (so the app can use the JDBC driver). My java file starts out:
import java.sql.*;
import oracle.jdbc.*;
import oracle.jdbc.pool.OracleDataSource;
class JDBCexample {
public static void main(String args[]) throws SQLException {
Connection conn;
Statement stmt;
ResultSet rset;
String query;
String sqlString;
String person_firstName;
String person_lastName;
String person_email;
int person_salary;
// connect to database
OracleDataSource ds = new OracleDataSource();
ds.setURL("jdbc:oracle:thin:myID/myPWD#192.168.0.1:1521:mySID");
conn = ds.getConnection();
// read something in database
stmt = conn.createStatement();
query = "SELECT first_name, last_name, email, salary FROM HR.Employees where rownum < 6";
rset = stmt.executeQuery(query);
while (rset.next()) {
person_firstName = rset.getString("first_name");
person_lastName = rset.getString("last_name");
person_email = rset.getString("email");
person_salary = rset.getInt("salary");
System.out.format(person_firstName + " " + person_lastName + " " + person_email + " %d%n", person_salary)
}
and so on...
QUESTION: How would I change the above code after I create a JDBC Connection Pool (named: myPool) and a JDBC Resource (named: myDBPool)? If it matters, I'm using Oracle 11.2, CentOS 6.2, GlassFish 3.1.1 with mod_jk and fronted by Apache 2.2 webserver, JDK 1.6. I don't have any clustering or load-balancing.
UPDATE 1: I thought this link was a good reference (see section titled: "Creating a Data Source Instance, Registering with JNDI, and Connecting"). But when I modify the above Java file as follows (just preparing the java file; haven't touched GlassFish yet),
// Add These:
import javax.naming.Context;
import javax.naming.InitialContext;
// Change from this:
// connect to database
OracleDataSource ds = new OracleDataSource();
ds.setURL("jdbc:oracle:thin:myID/myPWD#192.168.0.1:1521:mySID");
conn = ds.getConnection();
// To this:
// connect to database
Context ctext = new InitialContext();
OracleDataSource ds = (OracleDataSource)ctext.lookup("jdbc/myDBPool");
conn = ds.getConnection();
I get the errors:
JitterClass.java:67: unreported exception javax.naming.NamingException; must be caught or declared to be thrown
Context ctext = new InitialContext();
^
JitterClass.java:68: unreported exception javax.naming.NamingException; must be caught or declared to be thrown
OracleDataSource ds = (OracleDataSource)ctext.lookup("jdbc/myDBPool");
^
UPDATE 2: I cleared those compile errors using cyril's comments below (to throw all exceptions). Then I created JDBC Connection Pool and JDBC Resource, and the Ping was successful. So then I run the application from the client and observe the following error:
java.lang.ClassCastException : com.sun.gjc.spi.jdbc40.DataSource40 cannot be cast to oracle.jdbc.pool.OracleDataSource
At this point, if I add an include javax.sql.DataSource to the program, and change this line:
OracleDataSource ds = (OracleDataSource)ctext.lookup("jdbc/myDBPool");
to become this line:
DataSource ds = (DataSource)ctext.lookup("jdbc/myDBPool");
it compiles without errors. But now I'm confused... aren't we supposed to be using OracleDataSource here? Or, does GlassFish somehow implement OracleDataSource since I do see a setting for this connection pool for Datasource Classname set to oracle.jdbc.pool.OracleDataSource (?). Hoping someone can explain this.
Do pings on your connection pool work?
If not, check your pool configuration w/ http://docs.oracle.com/cd/E18930_01/html/821-2416/beamw.html#beanh
Once pings work and the JDBC Resource is configured, you should be able to access it in your app code through JNDI:
InitialContext context = new InitialContext();
DataSource ds = (DataSource) context.lookup("jdbc/myDBPool"); // or whatever name you used when creating the resource
conn = ds.getConnection();
Hope it helps,
RESPONSE TO UPDATE 1:
That's just the compiler telling you to formally catch or declare a checked exception which may be thrown by JNDI.
For testing purposes, the easiest way out of this (and future errors like this) is to just widen your method signature to throw all exceptions, i.e.:
public static void main(String args[]) throws /*SQL*/Exception {
RESPONSE TO UPDATE 2:
There's no reason to cast JDBC interfaces down to Oracle implementations unless you need to access any custom feature not specified in the JDBC spec. The purpose of a DataSource is to be a factory for Connections, whose API is defined in the JDBC interface, so that should be all you need. When you define a connection pool and resource in GlassFish, the app server is adding value by wrapping the JDBC driver classes and proxying them seamlessly for you as long as you stick to import java.sql.*. No need for oracle imports :) The main advantage being that if you ever decide to switch to MySQL or some other data store later on, your code is then portable and doesn't need any change.
To add to cyril's good answer:
Instead of the JNDI lookup, you can also use Resource Injection to set up your DataSource:
#Resource(name = "jdbc/Your_DB_Res")
private DataSource ds;
On startup, the application server will then inject the JDBC ressource. This section of Java EE Tutorial has more on that matter.
By using resource injection, you can reduce the amount of boilerplate code. This article introduces the concepts.
Besides adding the driver to your classpath, you should try adding the appserv-rt.jar file to your project's build path (the jar is located in Glassfish's lib directory). If you don't want to include all the other jars you should first create a library containing the appserv-rt jar and then add it to your project's build path.

Using Spring to Access an EJB Across Clusters in WebSphere using Grails

I have spent the last few days attempting to integrate a Grails (version 1.3.2) application with an EJB 2.1 application that is deployed on WebSphere 6.1. Once our grails apps are in production, they will be deployed to WebSphere as well. The EJB 2.1 application is widely used across our company and, in anything except a local development environment, is deployed to its own cluster. The way we handle this in our existing Java EE applications (all of which are non-Spring, non-Grails) is to bind a CORBA CosNaming Naming Context within each of our other clusters that can then be used to obtain references to our shared EJB 2.1 application. So, up to this point, if one of our application needed to interact with this application, they would do so using an approach like this:
String cosNameBinding = "ejbApp.HighAvail.cluster";
InitialContext initial = new InitialContext();
Context fedContext = (javax.naming.Context) initialCtx.lookup(cosNameBinding);
Then do the normal EJB-style lookup/narrow/invoke using the federated/CosNaming context:
Object ejbHomeAsObject = fedContext.lookup(jndiNameOfService);
EJBHome home = (EJBHome) PortableRemoteObject.narrow(ejbHomeAsObject, homeClass);
Object service = invokeMethod(homeClass, home, "create");
As you can see, there is a level of indirection that occurs here in order to go from the InitialContext to the federated naming Context that can be used to interact with the shared EJB application.
Running locally, I have both the Grails application and the EJB application deployed to the same server (non network deployment WAS, same profile&node). I have Spring configured like so:
beans = {
ejbJndi(org.springframework.jndi.JndiTemplate) {
environment = ["java.naming.factory.initial" :
"com.ibm.websphere.naming.WsnInitialContextFactory"]
}
crewMemberService(org.springframework.ejb.access.SimpleRemoteStatelessSessionProxyFactoryBean) {
jndiName="hotelService/ejb/HotelService"
businessInterface="com.company.appName.hotel.HotelService"
lookupHomeOnStartup="false"
cacheHome="false"
refreshHomeOnConnectFailure="true"
jndiTemplate = ref("ejbJndi")
}
}
And I can successfully inject ejb references into my Grails controllers and invoke them. However, WebSphere can only resolve the JNDI lookup because they are both deployed on the same server. When we move it to one of our development environments, we'll need jndi lookups for these services to go against the federated naming context.
So my questions are:
Is there a way to do this with the classes that are provided within Spring and if so could you give me an idea of how I would need up modify my Spring config to do so?
Given that there is no flexibility around how we deploy the other app or gain references to its services (we must use the federated context), should I consider extending JndiTemplate and do the necessary wiring myself?
If anyone has faced this situation I would be most appreciative for any insights you may be able to offer.
In case anyone has this same question down the road, I ended up implementing an extension to Spring's JndiTemplate and using that. Here is the code:
public class FederatedJndiTemplate extends org.springframework.jndi.JndiTemplate
{
protected static final String JNDI_CONTEXT_BINDING_NAME = "fed.context.jndiName";
/**
* Obtain a JNDI naming context for the specified federated naming context.
*
* #throws NamingException if no "fed.context.jndiName" has been specified in
* the environment properties for the jndiTemplate or the container throws a naming
* exception.
*/
#Override
protected Context createInitialContext() throws NamingException {
Properties props = super.getEnvironment();
if(!props.containsKey(JNDI_CONTEXT_BINDING_NAME)) {
throw new NamingException("You must specify the federated naming context JNDI binding name");
}
String jndiBinding = props.getProperty(JNDI_CONTEXT_BINDING_NAME);
InitialContext initCtx = new InitialContext();
Context fedCtx = (Context) initCtx.lookup(jndiBinding);
return fedCtx;
}
}
Then inside my resources.groovy, I just used this JndiTemplate:
ejbJndi(com.myCompany.spring.jndi.FederatedJndiTemplate) {
environment = [
"fed.context.jndiName":"myServices.HighAvail.Cluster"]
}
hotelService(org.springframework.ejb.access.SimpleRemoteStatelessSessionProxyFactoryBean) {
jndiName="hotelService/ejb/HotelService"
businessInterface="com.mycompany.appName.hotel.HotelService"
homeInterface="com.mycompany.appName.hotel.HotelServiceHome"
lookupHomeOnStartup="false"
jndiTemplate = ref("ejbJndi")
}

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