opendaylight/md-sal/sal-binding-broker/src/main/java/org/opendaylight/controller/sal/binding/codegen/impl/AbstractRuntimeCodeGenerator.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.controller.sal.binding.codegen.impl;
   9
  10 import com.google.common.base.Supplier;
  11 import com.google.common.collect.Iterables;
  12 import javassist.ClassPool;
  13 import javassist.CtClass;
  14 import javassist.CtMethod;
  15 import javassist.NotFoundException;
  16 import org.opendaylight.controller.sal.binding.api.rpc.RpcRouter;
  17 import org.opendaylight.controller.sal.binding.codegen.RpcIsNotRoutedException;
  18 import org.opendaylight.controller.sal.binding.spi.NotificationInvokerFactory;
  19 import org.opendaylight.yangtools.sal.binding.generator.util.JavassistUtils;
  20 import org.opendaylight.yangtools.yang.binding.BindingMapping;
  21 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  22 import org.opendaylight.yangtools.yang.binding.NotificationListener;
  23 import org.opendaylight.yangtools.yang.binding.RpcService;
  24 import org.opendaylight.yangtools.yang.binding.annotations.RoutingContext;
  25 import org.opendaylight.yangtools.yang.binding.util.ClassLoaderUtils;
  26
  27 import javax.annotation.concurrent.GuardedBy;
  28 import java.util.Map;
  29 import java.util.WeakHashMap;
  30
  31 abstract class AbstractRuntimeCodeGenerator implements org.opendaylight.controller.sal.binding.codegen.RuntimeCodeGenerator, NotificationInvokerFactory {
  32     @GuardedBy("this")
  33     private final Map<Class<? extends NotificationListener>, RuntimeGeneratedInvokerPrototype> invokerClasses = new WeakHashMap<>();
  34     private final CtClass brokerNotificationListener;
  35     protected final JavassistUtils utils;
  36
  37     protected AbstractRuntimeCodeGenerator(final ClassPool pool) {
  38         utils = JavassistUtils.forClassPool(pool);
  39
  40         /*
  41          * Make sure Javassist ClassPool sees the classloader of RpcService
  42          */
  43         utils.ensureClassLoader(RpcService.class);
  44
  45         brokerNotificationListener = utils.asCtClass(org.opendaylight.controller.sal.binding.api.NotificationListener.class);
  46     }
  47
  48     protected final CtClass getBrokerNotificationListener() {
  49         return brokerNotificationListener;
  50     }
  51
  52     protected abstract RuntimeGeneratedInvokerPrototype generateListenerInvoker(Class<? extends NotificationListener> cls);
  53     protected abstract <T extends RpcService> Supplier<T> directProxySupplier(final Class<T> serviceType);
  54     protected abstract <T extends RpcService> Supplier<T> routerSupplier(final Class<T> serviceType, RpcServiceMetadata metadata);
  55
  56     private RpcServiceMetadata getRpcMetadata(final CtClass iface) throws ClassNotFoundException, NotFoundException, RpcIsNotRoutedException {
  57         final RpcServiceMetadata metadata = new RpcServiceMetadata();
  58
  59         for (CtMethod method : iface.getMethods()) {
  60             if (isRpcMethodWithInput(iface, method)) {
  61                 final RpcMetadata routingPair = getRpcMetadata(method);
  62                 if (routingPair != null) {
  63                     metadata.addContext(routingPair.getContext());
  64                     metadata.addRpcMethod(method.getName(), routingPair);
  65
  66                     /*
  67                      * Force-load the RPC class representing the "input" of this RPC.
  68                      *
  69                      * FIXME: this is pre-existing side-effect of the original code, which
  70                      *        kept a reference to the loaded class, but it did not use it.
  71                      *
  72                      *        There was no explanation as to why forcing this load was
  73                      *        necessary. As far as I can tell now is that it forces the
  74                      *        resolution of method arguments, which would (according to
  75                      *        my reading of JLS) occur only when the method is invoked via
  76                      *        binding-aware class action, not when coming from
  77                      *        binding-independent world. Whether that makes sense or not,
  78                      *        remains to be investigated.
  79                      */
  80                     Thread.currentThread().getContextClassLoader().loadClass(routingPair.getInputType().getName());
  81                 } else {
  82                     throw new RpcIsNotRoutedException("RPC " + method.getName() + " from "+ iface.getName() +" is not routed");
  83                 }
  84             }
  85         }
  86
  87         return metadata;
  88     }
  89
  90
  91     private boolean isRpcMethodWithInput(final CtClass iface, final CtMethod method) throws NotFoundException {
  92         if(iface.equals(method.getDeclaringClass())
  93                 && method.getParameterTypes().length == 1) {
  94             final CtClass onlyArg = method.getParameterTypes()[0];
  95             if(onlyArg.isInterface() && onlyArg.getName().endsWith(BindingMapping.RPC_INPUT_SUFFIX)) {
  96                 return true;
  97             }
  98         }
  99         return false;
 100     }
 101
 102     private RpcMetadata getRpcMetadata(final CtMethod method) throws NotFoundException {
 103         final CtClass inputClass = method.getParameterTypes()[0];
 104         return rpcMethodMetadata(inputClass, inputClass, method.getName());
 105     }
 106
 107     private RpcMetadata rpcMethodMetadata(final CtClass dataClass, final CtClass inputClass, final String rpcMethod) throws NotFoundException {
 108         for (CtMethod method : dataClass.getMethods()) {
 109             if (method.getName().startsWith("get") && method.getParameterTypes().length == 0) {
 110                 for (Object annotation : method.getAvailableAnnotations()) {
 111                     if (annotation instanceof RoutingContext) {
 112                         boolean encapsulated = !method.getReturnType().equals(utils.asCtClass(InstanceIdentifier.class));
 113                         return new RpcMetadata(rpcMethod, ((RoutingContext)annotation).value(), method, encapsulated, inputClass);
 114                     }
 115                 }
 116             }
 117         }
 118
 119         for (CtClass iface : dataClass.getInterfaces()) {
 120             final RpcMetadata ret = rpcMethodMetadata(iface, inputClass, rpcMethod);
 121             if(ret != null) {
 122                 return ret;
 123             }
 124         }
 125         return null;
 126     }
 127
 128     private synchronized RuntimeGeneratedInvokerPrototype resolveInvokerClass(final Class<? extends NotificationListener> cls) {
 129         RuntimeGeneratedInvokerPrototype invoker = invokerClasses.get(cls);
 130         if (invoker != null) {
 131             return invoker;
 132         }
 133
 134         synchronized (utils) {
 135             invoker = ClassLoaderUtils.withClassLoader(cls.getClassLoader(), new Supplier<RuntimeGeneratedInvokerPrototype>() {
 136                 @Override
 137                 public RuntimeGeneratedInvokerPrototype get() {
 138                     return generateListenerInvoker(cls);
 139                 }
 140             });
 141         }
 142
 143         invokerClasses.put(cls, invoker);
 144         return invoker;
 145     }
 146
 147     @Override
 148     public final NotificationInvokerFactory getInvokerFactory() {
 149         return this;
 150     }
 151
 152     @Override
 153     public final <T extends RpcService> T getDirectProxyFor(final Class<T> serviceType) {
 154         synchronized (utils) {
 155             return ClassLoaderUtils.withClassLoader(serviceType.getClassLoader(), directProxySupplier(serviceType));
 156         }
 157     }
 158
 159     @Override
 160     public final <T extends RpcService> RpcRouter<T> getRouterFor(final Class<T> serviceType, final String name) throws RpcIsNotRoutedException {
 161         final RpcServiceMetadata metadata = ClassLoaderUtils.withClassLoader(serviceType.getClassLoader(), new Supplier<RpcServiceMetadata>() {
 162             @Override
 163             public RpcServiceMetadata get() {
 164                 try {
 165                     return getRpcMetadata(utils.asCtClass(serviceType));
 166                 } catch (ClassNotFoundException | NotFoundException e) {
 167                     throw new IllegalStateException(String.format("Failed to load metadata for class {}", serviceType), e);
 168                 }
 169             }
 170         });
 171
 172         if (Iterables.isEmpty(metadata.getContexts())) {
 173             throw new RpcIsNotRoutedException("Service doesn't have routing context associated.");
 174         }
 175
 176         synchronized (utils) {
 177             final T instance = ClassLoaderUtils.withClassLoader(serviceType.getClassLoader(), routerSupplier(serviceType, metadata));
 178             return new RpcRouterCodegenInstance<T>(name, serviceType, instance, metadata.getContexts());
 179         }
 180     }
 181
 182     @Override
 183     public NotificationInvoker invokerFor(final NotificationListener instance) {
 184         final Class<? extends NotificationListener> cls = instance.getClass();
 185         final RuntimeGeneratedInvokerPrototype prototype = resolveInvokerClass(cls);
 186
 187         try {
 188             return RuntimeGeneratedInvoker.create(instance, prototype);
 189         } catch (InstantiationException | IllegalAccessException e) {
 190             throw new IllegalStateException(String.format("Failed to create invoker for %s", instance), e);
 191         }
 192     }
 193 }