ProfileCmpSlee10WrapperClassGenerator.java

package org.mobicents.slee.container.deployment.profile;

import java.util.Map;

import javassist.CannotCompileException;
import javassist.CtClass;
import javassist.CtConstructor;
import javassist.CtMethod;
import javassist.CtNewConstructor;
import javassist.CtNewMethod;

import javax.slee.SLEEException;
import javax.slee.profile.ReadOnlyProfileException;

import org.apache.log4j.Logger;
import org.mobicents.slee.container.component.ProfileSpecificationComponent;
import org.mobicents.slee.container.component.deployment.ClassPool;
import org.mobicents.slee.container.component.deployment.jaxb.descriptors.ProfileSpecificationDescriptorImpl;
import org.mobicents.slee.container.deployment.ClassUtils;
import org.mobicents.slee.container.profile.AbstractProfileCmpSlee10Wrapper;
import org.mobicents.slee.container.profile.ProfileObject;

/**
 * 
 * The Profile CMP Slee 1.0 Wrapper is an object that implements the Profile CMP
 * Interface, wrapping the SLEE 1.1 real profile concrete object in a SLEE 1.0
 * compatible interface. This class generates such objects.
 * 
 * @author martins
 * 
 */
public class ProfileCmpSlee10WrapperClassGenerator {

	private static final Logger logger = Logger.getLogger(ProfileCmpSlee10WrapperClassGenerator.class);
	
	/**
	 * the component to process
	 */
	private final ProfileSpecificationComponent component;

	/**
	 * 
	 * @param component
	 */
	public ProfileCmpSlee10WrapperClassGenerator(ProfileSpecificationComponent component) {
		this.component = component;		
	}

	/**
	 * 
	 * @throws Exception
	 */
	public void generateClass() throws Exception {
		
		ProfileSpecificationDescriptorImpl descriptor = component.getDescriptor();
		ClassPool pool = component.getClassPool();
				
		String profileCmpInterfaceName = descriptor.getProfileCMPInterface().getProfileCmpInterfaceName();
		String wrapperClassName =  profileCmpInterfaceName + "Slee10Wrapper" ;
		CtClass profileCmpInterface = null;
		CtClass wrapperClass = null;
		try {
			profileCmpInterface = pool.get(profileCmpInterfaceName);
			wrapperClass = pool.makeClass(wrapperClassName);
			wrapperClass.setSuperclass(pool.get(AbstractProfileCmpSlee10Wrapper.class.getName()));
			wrapperClass.addInterface(profileCmpInterface);			
		} catch (Exception e) {
			throw new SLEEException(e.getMessage(),e);
		}
		
		// implement only methods from profile cmp and management interface that are also on user defined local object interface
		Map<String, CtMethod> methodsToImplement = ClassUtils.getInterfaceMethodsFromInterface(profileCmpInterface);
		
		// generate constructor
	    try {
	      CtClass[] constructorParameters = new CtClass[] { pool.get(ProfileObject.class.getName()) };
	      String constructorBody = "{ super($$); }";
	      CtConstructor constructor = CtNewConstructor.make(constructorParameters, new CtClass[]{}, constructorBody , wrapperClass);
	      wrapperClass.addConstructor(constructor);
	    } catch (CannotCompileException e) {
	      throw new SLEEException(e.getMessage(),e);
	    }
		
	    // implement methods delegating to an object casted to the profile cmp concrete class generated by SLEE
	    String profileCmpConcreteClassName = component.getProfileCmpConcreteClass().getName();
	    for (CtMethod ctMethod : methodsToImplement.values()) {
			implementMethod(wrapperClass, ctMethod,"(("+profileCmpConcreteClassName+")profileObject.getProfileConcrete())");
		}
		// generate class file
		try {
			wrapperClass.writeFile(component.getDeploymentDir().getAbsolutePath());
			if (logger.isDebugEnabled()) {
				logger.debug("Profile CMP SLEE 1.0 Wrapper Class " + wrapperClassName + " generated in the following path " + component.getDeploymentDir().getAbsolutePath());
			}
		}
		catch (Exception e) {
			throw new SLEEException(e.getMessage(), e);
		}
		finally {
			wrapperClass.defrost();
		}
		// load it and store it in the component
		try {			
			component.setProfileCmpSlee10WrapperClass(component.getClassLoader().loadClass(wrapperClassName));
		}
		catch (ClassNotFoundException e) {
			throw new SLEEException(e.getMessage(),e);
		}
	}

	private void implementMethod(CtClass concreteClass, CtMethod method, String interceptorAccess) throws Exception {
		// copy method to concrete class
		CtMethod newMethod = CtNewMethod.copy( method, concreteClass, null );
		// generate body
		String returnStatement = method.getReturnType().equals(CtClass.voidType) ? "" : "return ($r)";
		String body=
			"{ " 
			+ "	try {"
			+ 		returnStatement + interceptorAccess +'.'+ method.getName()+"($$);" 
			+ "	} catch ("+ReadOnlyProfileException.class.getName()+" e) {"
			+ "		throw new "+UnsupportedOperationException.class.getName()+"(e.getMessage(),e);" 
			+ "	}"
			+ "}";
		if(logger.isDebugEnabled())
		{
			logger.debug("Instrumented method, name:"+method.getName()+", with body:\n"+body);
		}
		newMethod.setBody(body);
		// add to concrete class  
		concreteClass.addMethod(newMethod);
	}
}