I am using Tomcat server in java and wanted to be able to access the ServletContext from the restlet Resource in order to access my cached DataSource object (to pool mysql connections). org.restlet.resource.Resource comes with a Context object but that is not in any way related to the ServletContext. So after some googling around, I found the following:
final String contextKey = "org.restlet.ext.servlet.ServletContext";
final String poolKey = "MyCachedDBPool";
final Map<String, Object> attrs = getContext().getAttributes();
final ServletContext ctx = (ServletContext) attrs.get(contextKey);
if (ctx == null) {
throw new Exception("Cannot find ServletContext: " + contextKey);
}
final DataSource ds = (DataSource) ctx.getAttribute(poolKey);
if (ds == null) {
throw new DetourQAException("DataSource not stored in context"
+ poolKey + "attr");
}
But it returns null for the ServletContext. Has anybody successfully accessed the ServletContext from within the restlet resource and how did you do it?
If this is not the recommended way to do connection pooling, what is the best way to do connection pooling in the restlet?
This was the way to do it before Restlet 2.0 (actually I think they changed it around 2.0-M5, or so). Anyway, the way you'd do it now is:
ServletContext sc = (ServletContext) getContext().getServerDispatcher().getContext().getAttributes().get( "org.restlet.ext.servlet.ServletContext" );
Hope that helps.
Related
I have my web services jar file deployed under webapps\nyx\WEB-INF\services in my tomcat server. Now I am trying to get no of active sessions using below code inside a web service method.
MBeanServer mBeanServer = ManagementFactory.getPlatformMBeanServer();
ObjectName objectName = new ObjectName("Catalina:type=Manager,context=/nyx/services,host=localhost");
Object activeSessions =mBeanServer.getAttribute(objectName,"activeSessions");
But this gives me Instance not found exception.
Can someone help me with the value for the context attribute?
Try to refer to this SO question, reading your code the first thing that i think is try using JMX (Java Management eXtension)
Something like this:
JMXServiceURL url = new JMXServiceURL("service:jmx:rmi:///jndi/rmi://localhost:9999/jmxrmi");
try(JMXConnector jmxc = JMXConnectorFactory.connect(url)) {
MBeanServerConnection mbsc = jmxc.getMBeanServerConnection();
ObjectName mbeanName = new ObjectName("Catalina:type=Manager,context=/,host=localhost");
Object value = mbsc.getAttribute(mbeanName, "activeSessions");
}
EDIT
If you need to retrieve the number of session locally your code should be fine, try with your code but getting the context at runtime.
Override the init method:
#Override
public void init(final ServletConfig config) throws ServletException {
context = config.getServletContext().getContextPath();
}
Then pass it as ObjectName parameter:
ObjectName objectName = new ObjectName("Catalina:type=Manager,context="+context+",host=localhost");
I would like to know how JMS and RMI uses JNDI ,i would also appreciate any snippets of code explaining it .
Thanks
The Java Naming and Directory Interface (JNDI) provides a standard way of accessing naming and directory services
Example Obtaining the initial JNDI context:
import javax.naming.*;
private static InitialContext ctx = null;
...
public static InitialContext getInitialContext( ) throws NamingException {
if (ctx == null) {
Hashtable env = new Hashtable( );
env.put(Context.INITIAL_CONTEXT_FACTORY,
"weblogic.jndi.WLInitialContextFactory");
env.put(Context.PROVIDER_URL,
"t3://myserver:8001");
ctx = new InitialContext(env);
}
return ctx;
}
See Chapter 4. Using JNDI and RMI of WebLogic: The Definitive Guide for more details.
I need to process a file on the app startup and create some objects out of the given information and then add them as beans to the camel context. Eg: Mysql DataSource object.
public static void load(CamelContext context) throws Exception {
JndiRegistry registry = (JndiRegistry) context.getRegistry();
PropertiesComponent pc = context.getComponent("properties", PropertiesComponent.class);
pc.setLocation("classpath:mysql.properties");
for (String mysql: pc.parseUri("{{mysqlConfigs}}").split(",")) {
String MYSQL_DB_URL = pc.parseUri("{{" + mysql + ".url}}");
String MYSQL_DB_USERNAME = pc.parseUri("{{" + mysql + ".username}}");
String MYSQL_DB_PASSWORD = pc.parseUri("{{" + mysql + ".passwd}}");
String DB_NAME = pc.parseUri("{{" + mysql + ".name}}");
MysqlDataSource mysqlDS = new MysqlDataSource();
mysqlDS.setURL(MYSQL_DB_URL);
mysqlDS.setUser(MYSQL_DB_USERNAME);
mysqlDS.setPassword(MYSQL_DB_PASSWORD);
registry.bind(DB_NAME, (DataSource) mysqlDS);
}
}
The code throws exception,
org.apache.camel.impl.PropertyPlaceholderDelegateRegistry cannot be cast to org.apache.camel.impl.JndiRegistry
Same error if I try to cast it to SimpleRegistry. Is there way this can be achieved this way or if any other methodology shall be adopted given that no more contexts are to be added.
Try:
JndiRegistry registry = context.getRegistry(JndiRegistry.class);
I am trying to call RES server (v 7.1) from EAR deployed on WAS (8.5) instance. I was able to invoke rule server from standalone program and its working without any problems.
However my main problem is to invoke EJB deployed on RES server remotely from another EAR deployed on some other WAS instance. In this case we are not able to look-up the EJB remotely.
As per below thread we should bypass the EJB3 IlrSessionFactory API and should use Java EJB API to look up rule sessions directly.
http://www-01.ibm.com/support/docview.wss?uid=swg21586621
Recommendation from IBM is to use standard java api for ejb lookup or to upgrade to Rule Server 7.5 (latest 8.x).
Code snippet
// Initialization
Map<String, Object> outputParms = null;
IlrStatelessSession session=null;
IlrSessionResponse response=null;
// IlrSessionFactory factory = getFactory();
try {
sessionFactory = JRulesInvoker.getFactory();
Hashtable<String, String> env = new Hashtable<String, String>();
env.put(Context.INITIAL_CONTEXT_FACTORY,"com.ibm.websphere.naming.WsnInitialContextFactory");
env.put(Context.PROVIDER_URL,"corbaloc:iiop:localhost:28004");
Context ctx = new InitialContext(env);
Object lookupResult = ctx.lookup("ilog.rules.res.session.impl.ejb3.IlrStatelessSessionRemote");
PortableRemoteObject aPortableRemoteObject = new PortableRemoteObject();
session = (IlrStatelessSession) aPortableRemoteObject.narrow(lookupResult, IlrStatelessSession.class);
IlrPath path = new IlrPath(ruleApp, ruleSet);
IlrSessionRequest request = sessionFactory.createRequest();
request.setRulesetPath(path);
request.setInputParameters(inputParms);
request.getTraceFilter().setInfoTotalRulesFired(true);
request.getTraceFilter().setInfoExecutionEvents(true);
request.setTraceEnabled(true);
// session = sessionFactory.createStatelessSession();
System.out.println("created session " + IlrJNDIConstants.STATELESS_SESSION_EJB3_NAME);
response = session.execute(request);
System.out.println(response.getRulesetExecutionTrace().getTotalRulesFired() + " rule(s) fired.");
System.out.println("Execution output=" + response.getRulesetExecutionOutput());
// Return the result(s)
outputParms = response.getOutputParameters();
if (logger.isEnabledFor(Level.DEBUG)) {
if (response.getRulesetExecutionOutput() != null) {
logger.debug("RuleSet execution output: \n" + response.getRulesetExecutionOutput());
}
}
}catch (IlrSessionCreationException cx) {
if (logger.isEnabledFor(Level.ERROR)) {
logger.error(cx.getMessage(), cx);
}
} catch (IlrSessionException e) {
if (logger.isEnabledFor(Level.ERROR)) {
logger.error(e.getMessage(), e);
}
} catch (NamingException e) {
if (logger.isEnabledFor(Level.ERROR)) {
logger.error(e.getMessage(), e);
}
}
Error
Context: idewas/nodes/ide/servers/server1, name: ilog.rules.res.session.impl.ejb3.IlrStatelessSessionRemote: First component in name ilog.rules.res.session.impl.ejb3.IlrStatelessSessionRemote not found.
javax.naming.NameNotFoundException: Context: idewas/nodes/ide/servers/server1, name: ilog.rules.res.session.impl.ejb3.IlrStatelessSessionRemote: First component in name ilog.rules.res.session.impl.ejb3.IlrStatelessSessionRemote not found. [Root exception is org.omg.CosNaming.NamingContextPackage.NotFound: IDL:omg.org/CosNaming/NamingContext/NotFound:1.0]
at com.ibm.ws.naming.jndicos.CNContextImpl.mapNotFoundException(CNContextImpl.java:4563)
at com.ibm.ws.naming.jndicos.CNContextImpl.doLookup(CNContextImpl.java:1821)
at com.ibm.ws.naming.jndicos.CNContextImpl.doLookup(CNContextImpl.java:1776)
at com.ibm.ws.naming.jndicos.CNContextImpl.lookupExt(CNContextImpl.java:1433)
at com.ibm.ws.naming.jndicos.CNContextImpl.lookup(CNContextImpl.java:615)
at com.ibm.ws.naming.util.WsnInitCtx.lookup(WsnInitCtx.java:165)
at com.ibm.ws.naming.util.WsnInitCtx.lookup(WsnInitCtx.java:179)
at org.apache.aries.jndi.DelegateContext.lookup(DelegateContext.java:161)
at javax.naming.InitialContext.lookup(InitialContext.java:436)
Check in the SystemOut.log of the RES server what are the binding names for EJBs as it looks like there is no ilog.rules.res.session.impl.ejb3.IlrStatelessSessionRemote there. Also if you have two servers on the same host under the same name e.g. server1 you may have interoberability issues and need to set JVM property com.ibm.websphere.orb.uniqueServerName to true. For more details check the following page Application access problems
Does anyone now a way to obtain server Context using Embeddable API (using org.glassfish.embeddable.GlassFish, not javax.ejb.embeddable.EJBContainer)?
It would be possible if there's a way to obtain EJBContainer from a running Glassfish, but I can't find even the list of services available for lookup.
Here's a workaround - we can obtain InitialContext as an external client.
For the full explanation check EJB_FAQ . This way at least remote EJBs could be tested:
So the full example will look like:
//Start GF
GlassFishRuntime gfRuntime = GlassFishRuntime.bootstrap();
GlassFish gf = gfRuntime.newGlassFish();
gf.start();
//Deploy application with EJBs
Deployer deployer = gf.getService(Deployer.class);
String deployedApp = deployer.deploy(new File(...), "--force=true");
//Create InitialContext
Properties props = new Properties();
props.setProperty("java.naming.factory.initial",
"com.sun.enterprise.naming.SerialInitContextFactory");
props.setProperty("java.naming.factory.url.pkgs",
"com.sun.enterprise.naming");
props.setProperty("java.naming.factory.state",
"com.sun.corba.ee.impl.presentation.rmi.JNDIStateFactoryImpl");
props.setProperty("org.omg.CORBA.ORBInitialHost", "localhost");
props.setProperty("org.omg.CORBA.ORBInitialPort", "3700");
InitialContext ic = new InitialContext(props);
//Lookup EJBs
ic.lookup(...)
//Stop GF
gf.stop();
gfRuntime.shutdown();
//CORBA stuck thread, have to kill it manually
System.exit(0);
Note there's a System.exit(0) at the end - com.sun.corba.ee.impl.javax.rmi.CORBA.Util.KeepAlive thread is running even after the server stop preventing JVM from stopping...
As far as I know, you can initialize the InitialContext class to obtain a context, that can further be used to perform the lookup. This was tested, and found to work in the context of looking up an EJB, deployed in the embedded container. The EJB was not configured to allow access to specific roles, in which case the com.sun.appserv.security.ProgrammaticLogin class (not exposed via the Embeddable EJB API) might help; this was not tested, but is the recommended way to initialize the Principal for the thread accessing an EJB.
A more or less complete example that runs from Maven and uses the embedded Glassfish dependency in a POM (not reproduced here, for brevity) follows:
The EJB interface:
public interface EchoManager
{
String echo(String message);
}
The Session Bean:
#Local(EchoManager.class)
#Stateless
#EJB(name="java:global/glassfish-ejb-validation/EchoManager",beanInterface=EchoManager.class)
public class EchoManagerBean implements EchoManager
{
public String echo(String message)
{
return message;
}
}
The unit test:
public class EchoManagerTest
{
#Rule
public TestName testMethod = new TestName();
private static final Logger logger = Logger.getLogger(EchoManagerTest.class.getName());
#Test
public void testEchoWithGlassfishRuntime() throws Exception
{
logger.info("Starting execution of test" + testMethod.getMethodName());
GlassFish glassFish = null;
Deployer deployer = null;
String appName = null;
try
{
//Setup
BootstrapProperties bootstrapProps = new BootstrapProperties();
GlassFishRuntime glassFishRuntime = GlassFishRuntime.bootstrap(bootstrapProps);
GlassFishProperties gfProps = new GlassFishProperties();
glassFish = glassFishRuntime.newGlassFish(gfProps);
glassFish.start();
deployer = glassFish.getDeployer();
ScatteredArchive archive = new ScatteredArchive("glassfish-ejb-validation", Type.JAR);
archive.addClassPath(new File("target", "classes"));
archive.addClassPath(new File("target", "test-classes"));
appName = deployer.deploy(archive.toURI(), "--force=true");
// Setup the context
InitialContext context = new InitialContext();
//Execute (after lookup the EJB from the context)
EchoManager manager = (EchoManager) context.lookup("java:global/glassfish-ejb-validation/EchoManager");
String echo = manager.echo("Hello World");
//Verify
assertEquals("Hello World", echo);
}
finally
{
if(deployer != null && appName != null)
{
deployer.undeploy(appName);
}
if(glassFish != null)
{
glassFish.stop();
glassFish.dispose();
}
logger.info("Ending execution of test" + testMethod.getMethodName());
}
}
}
Note that the EJB is deployed with a explicit portable JNDI name (via the #EJB annotation), as I have other tests that use the public embeddable EJB API in other tests, and it is more or less difficult to specify an application name in such tests; each test execution might result in a different JNDI name for the EJB, thus necessitating an explicit JNDI name to be specified.