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.eclipse.xtext.xbase.lib.Extension;
  17 import org.opendaylight.controller.sal.binding.api.rpc.RpcRouter;
  18 import org.opendaylight.controller.sal.binding.codegen.RpcIsNotRoutedException;
  19 import org.opendaylight.controller.sal.binding.spi.NotificationInvokerFactory;
  20 import org.opendaylight.yangtools.sal.binding.generator.util.JavassistUtils;
  21 import org.opendaylight.yangtools.yang.binding.BindingMapping;
  22 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
  23 import org.opendaylight.yangtools.yang.binding.NotificationListener;
  24 import org.opendaylight.yangtools.yang.binding.RpcService;
  25 import org.opendaylight.yangtools.yang.binding.annotations.RoutingContext;
  26 import org.opendaylight.yangtools.yang.binding.util.ClassLoaderUtils;
  27
  28 import javax.annotation.concurrent.GuardedBy;
  29 import java.util.Map;
  30 import java.util.WeakHashMap;
  31
  32 abstract class AbstractRuntimeCodeGenerator implements org.opendaylight.controller.sal.binding.codegen.RuntimeCodeGenerator, NotificationInvokerFactory {
  33     @GuardedBy("this")
  34     private final Map<Class<? extends NotificationListener>, RuntimeGeneratedInvokerPrototype> invokerClasses = new WeakHashMap<>();
  35     private final CtClass brokerNotificationListener;
  36
  37     @Extension
  38     protected final JavassistUtils utils;
  39
  40     protected AbstractRuntimeCodeGenerator(final ClassPool pool) {
  41         utils = JavassistUtils.forClassPool(pool);
  42
  43         /*
  44          * Make sure Javassist ClassPool sees the classloader of RpcService
  45          */
  46         utils.ensureClassLoader(RpcService.class);
  47
  48         brokerNotificationListener = utils.asCtClass(org.opendaylight.controller.sal.binding.api.NotificationListener.class);
  49     }
  50
  51     protected final CtClass getBrokerNotificationListener() {
  52         return brokerNotificationListener;
  53     }
  54
  55     protected abstract RuntimeGeneratedInvokerPrototype generateListenerInvoker(Class<? extends NotificationListener> cls);
  56     protected abstract <T extends RpcService> Supplier<T> directProxySupplier(final Class<T> serviceType);
  57     protected abstract <T extends RpcService> Supplier<T> routerSupplier(final Class<T> serviceType, RpcServiceMetadata metadata);
  58
  59     private RpcServiceMetadata getRpcMetadata(final CtClass iface) throws ClassNotFoundException, NotFoundException, RpcIsNotRoutedException {
  60         final RpcServiceMetadata metadata = new RpcServiceMetadata();
  61
  62         for (CtMethod method : iface.getMethods()) {
  63             if (isRpcMethodWithInput(iface, method)) {
  64                 final RpcMetadata routingPair = getRpcMetadata(method);
  65                 if (routingPair != null) {
  66                     metadata.addContext(routingPair.getContext());
  67                     metadata.addRpcMethod(method.getName(), routingPair);
  68
  69                     /*
  70                      * Force-load the RPC class representing the "input" of this RPC.
  71                      *
  72                      * FIXME: this is pre-existing side-effect of the original code, which
  73                      *        kept a reference to the loaded class, but it did not use it.
  74                      *
  75                      *        There was no explanation as to why forcing this load was
  76                      *        necessary. As far as I can tell now is that it forces the
  77                      *        resolution of method arguments, which would (according to
  78                      *        my reading of JLS) occur only when the method is invoked via
  79                      *        binding-aware class action, not when coming from
  80                      *        binding-independent world. Whether that makes sense or not,
  81                      *        remains to be investigated.
  82                      */
  83                     Thread.currentThread().getContextClassLoader().loadClass(routingPair.getInputType().getName());
  84                 } else {
  85                     throw new RpcIsNotRoutedException("RPC " + method.getName() + " from "+ iface.getName() +" is not routed");
  86                 }
  87             }
  88         }
  89
  90         return metadata;
  91     }
  92
  93
  94     private boolean isRpcMethodWithInput(final CtClass iface, final CtMethod method) throws NotFoundException {
  95         if(iface.equals(method.getDeclaringClass())
  96                 && method.getParameterTypes().length == 1) {
  97             final CtClass onlyArg = method.getParameterTypes()[0];
  98             if(onlyArg.isInterface() && onlyArg.getName().endsWith(BindingMapping.RPC_INPUT_SUFFIX)) {
  99                 return true;
 100             }
 101         }
 102         return false;
 103     }
 104
 105     private RpcMetadata getRpcMetadata(final CtMethod method) throws NotFoundException {
 106         final CtClass inputClass = method.getParameterTypes()[0];
 107         return rpcMethodMetadata(inputClass, inputClass, method.getName());
 108     }
 109
 110     private RpcMetadata rpcMethodMetadata(final CtClass dataClass, final CtClass inputClass, final String rpcMethod) throws NotFoundException {
 111         for (CtMethod method : dataClass.getMethods()) {
 112             if (method.getName().startsWith("get") && method.getParameterTypes().length == 0) {
 113                 for (Object annotation : method.getAvailableAnnotations()) {
 114                     if (annotation instanceof RoutingContext) {
 115                         boolean encapsulated = !method.getReturnType().equals(utils.asCtClass(InstanceIdentifier.class));
 116                         return new RpcMetadata(rpcMethod, ((RoutingContext)annotation).value(), method, encapsulated, inputClass);
 117                     }
 118                 }
 119             }
 120         }
 121
 122         for (CtClass iface : dataClass.getInterfaces()) {
 123             final RpcMetadata ret = rpcMethodMetadata(iface, inputClass, rpcMethod);
 124             if(ret != null) {
 125                 return ret;
 126             }
 127         }
 128         return null;
 129     }
 130
 131     private synchronized RuntimeGeneratedInvokerPrototype resolveInvokerClass(final Class<? extends NotificationListener> cls) {
 132         RuntimeGeneratedInvokerPrototype invoker = invokerClasses.get(cls);
 133         if (invoker != null) {
 134             return invoker;
 135         }
 136
 137         synchronized (utils) {
 138             invoker = ClassLoaderUtils.withClassLoader(cls.getClassLoader(), new Supplier<RuntimeGeneratedInvokerPrototype>() {
 139                 @Override
 140                 public RuntimeGeneratedInvokerPrototype get() {
 141                     return generateListenerInvoker(cls);
 142                 }
 143             });
 144         }
 145
 146         invokerClasses.put(cls, invoker);
 147         return invoker;
 148     }
 149
 150     @Override
 151     public final NotificationInvokerFactory getInvokerFactory() {
 152         return this;
 153     }
 154
 155     @Override
 156     public final <T extends RpcService> T getDirectProxyFor(final Class<T> serviceType) {
 157         synchronized (utils) {
 158             return ClassLoaderUtils.withClassLoader(serviceType.getClassLoader(), directProxySupplier(serviceType));
 159         }
 160     }
 161
 162     @Override
 163     public final <T extends RpcService> RpcRouter<T> getRouterFor(final Class<T> serviceType, final String name) throws RpcIsNotRoutedException {
 164         final RpcServiceMetadata metadata = ClassLoaderUtils.withClassLoader(serviceType.getClassLoader(), new Supplier<RpcServiceMetadata>() {
 165             @Override
 166             public RpcServiceMetadata get() {
 167                 try {
 168                     return getRpcMetadata(utils.asCtClass(serviceType));
 169                 } catch (ClassNotFoundException | NotFoundException e) {
 170                     throw new IllegalStateException(String.format("Failed to load metadata for class {}", serviceType), e);
 171                 }
 172             }
 173         });
 174
 175         if (Iterables.isEmpty(metadata.getContexts())) {
 176             throw new RpcIsNotRoutedException("Service doesn't have routing context associated.");
 177         }
 178
 179         synchronized (utils) {
 180             final T instance = ClassLoaderUtils.withClassLoader(serviceType.getClassLoader(), routerSupplier(serviceType, metadata));
 181             return new RpcRouterCodegenInstance<T>(name, serviceType, instance, metadata.getContexts());
 182         }
 183     }
 184
 185     @Override
 186     public NotificationInvoker invokerFor(final NotificationListener instance) {
 187         final Class<? extends NotificationListener> cls = instance.getClass();
 188         final RuntimeGeneratedInvokerPrototype prototype = resolveInvokerClass(cls);
 189
 190         try {
 191             return RuntimeGeneratedInvoker.create(instance, prototype);
 192         } catch (InstantiationException | IllegalAccessException e) {
 193             throw new IllegalStateException(String.format("Failed to create invoker for %s", instance), e);
 194         }
 195     }
 196 }