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This artifact provides a single jar that contains all classes required to use remote Jakarta Enterprise Beans and Jakarta Messaging, including all dependencies. It is intended for use by those not using maven, maven users should just import the Jakarta Enterprise Beans and Jakarta Messaging BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up with different versions on classes on the class path).

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/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2013, Red Hat, Inc., and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */

package org.jboss.ejb.client;

import javax.ejb.EJBObject;
import java.lang.reflect.Method;

/**
 * A {@link EJBClientInterceptor} which is responsible for intercepting the returning value of getEJBHome method
 * on a {@link javax.ejb.EJBObject} proxy. This interceptor just lets the invocation proceed in its {@link #handleInvocation(EJBClientInvocationContext)}
 * method. However, in its {@link #handleInvocationResult(EJBClientInvocationContext)} method it does the following:
 * 
 * Check to see if the invocation is happening on a EJBObject proxy. If it finds that the invocation is not
 * on a EJBObject proxy, then the {@link #handleInvocationResult(EJBClientInvocationContext)} just returns back the
 * original result.
 * 
 * 
 * Check to see if the invoked method is a "getEJBHome" method. If the invocation is not for a "getEJBHome" method, then
 * the {@link #handleInvocationResult(EJBClientInvocationContext)} just returns back the original result.
 * 
 * 
 * Check to see if the original returned instance is a {@link EJBClient#isEJBProxy(Object) EJB proxy}.
 * If it isn't, then the {@link #handleInvocationResult(EJBClientInvocationContext)} method just returns back the
 * original result. If it finds that it's an EJB proxy then the {@link #handleInvocationResult(EJBClientInvocationContext)}
 * recreates the proxy/proxies by using the {@link org.jboss.ejb.client.EJBInvocationHandler#getEjbClientContextIdentifier() EJB client context identifier}
 * that's applicable to the EJBObject proxy on which this invocation was done. This way, the EJB home proxies returned
 * by calls to "getEJBHome" methods on the EJBObject proxy will always be associated with the EJB client context identifier
 * that's applicable to the EJBObject proxy
 * 
 * 
 *
 * @author Jaikiran Pai
 */
final class EJBObjectInterceptor implements EJBClientInterceptor {
    @Override
    public void handleInvocation(final EJBClientInvocationContext invocationContext) throws Exception {
        // we just pass along the request
        invocationContext.sendRequest();

    }

    @Override
    public Object handleInvocationResult(final EJBClientInvocationContext invocationContext) throws Exception {
        final Object originalResult = invocationContext.getResult();
        if (originalResult == null) {
            return originalResult;
        }
        // if the original result isn't a EJB proxy, then we just return back the original result
        if (!EJBClient.isEJBProxy(originalResult)) {
            return originalResult;
        }
        // if it's not an invocation on a EJBObject view, then just return back the original result
        if (!isEJBObjectInvocation(invocationContext)) {
            return originalResult;
        }
        // if it's not a "getEJBHome()" method invocation then just return back the original result
        if (!isGetEJBHomeMethodInvocation(invocationContext)) {
            return originalResult;
        }
        // at this point we have identified the invocation to be "getEJBHome()" method invocation on the EJBObject view.
        // So we now update that returned EJB home proxy to use the EJB client context identifier that's applicable for the
        // EJBObject proxy on which this invocation was done
        final Object ejbProxy = originalResult;
        // we *don't* change the locator of the original proxy
        final EJBLocator ejbLocator = EJBClient.getLocatorFor(ejbProxy);
        // get the EJB client context identifier (if any) that's applicable for the EJBObject view on which this
        // invocation happened
        final EJBClientContextIdentifier ejbClientContextIdentifier = invocationContext.getInvocationHandler().getEjbClientContextIdentifier();
        // now recreate the returned EJB home proxy with the EJB client context identifier
        return EJBClient.createProxy(ejbLocator, ejbClientContextIdentifier);
    }

    /**
     * Returns true if the invocation happened on a EJB home view. Else returns false.
     *
     * @param invocationContext
     * @return
     */
    private boolean isEJBObjectInvocation(final EJBClientInvocationContext invocationContext) {
        return invocationContext.getInvokedProxy() instanceof EJBObject;
    }

    /**
     * Returns true if the invocation is for a getEJBHome method. Else returns false.
     *
     * @param invocationContext The invocation context
     * @return
     */
    private boolean isGetEJBHomeMethodInvocation(final EJBClientInvocationContext invocationContext) {
        final Method invokedMethod = invocationContext.getInvokedMethod();
        return invokedMethod.getName().equals("getEJBHome");
    }

}