content: package act.controller.bytecode;
  
  /*-
   * #%L
   * ACT Framework
   * %%
   * Copyright (C) 2014 - 2017 ActFramework
   * %%
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   * 
   *      http://www.apache.org/licenses/LICENSE-2.0
   * 
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   * #L%
   */
  
  import act.app.App;
  import act.asm.ClassVisitor;
  import act.asm.MethodVisitor;
  import act.asm.Type;
  import act.controller.meta.ControllerClassMetaInfo;
  import act.controller.meta.ControllerClassMetaInfoHolder;
  import act.controller.meta.HandlerMethodMetaInfo;
  import act.util.AppByteCodeEnhancer;
  import org.osgl.$;
  
  /**
   * Enhance controllers (classes with either request handler method or
   * interceptor methods)
   */
  public class ControllerEnhancer extends AppByteCodeEnhancer<ControllerEnhancer> {
      private ControllerClassMetaInfoHolder classInfoHolder;
      private String className;
  
      public ControllerEnhancer() {
      }
  
      public ControllerEnhancer(ClassVisitor cv, ControllerClassMetaInfoHolder infoHolder) {
          super(_F.isController(infoHolder), cv);
          this.classInfoHolder = infoHolder;
      }
  
      @Override
      public AppByteCodeEnhancer app(App app) {
          this.classInfoHolder = app.classLoader();
          return super.app(app);
      }
  
      @Override
      protected Class<ControllerEnhancer> subClass() {
          return ControllerEnhancer.class;
      }
  
      @Override
      protected void reset() {
          this.className = null;
          super.reset();
      }
  
      @Override
      public void visit(int version, int access, String name, String signature, String superName, String[] interfaces) {
          super.visit(version, access, name, signature, superName, interfaces);
          className = Type.getObjectType(name).getClassName();
      }
  
      @Override
      public MethodVisitor visitMethod(int access, String name, String desc, String signature, String[] exceptions) {
          MethodVisitor mv = super.visitMethod(access, name, desc, signature, exceptions);
          HandlerMethodMetaInfo info = methodInfo(name);
          if (null == info) {
              return mv;
          }
          logger.debug(">>>About to enhance handler: %s", name);
          return new HandlerEnhancer(mv, info, access, name, desc, signature, exceptions);
      }
  
      private HandlerMethodMetaInfo methodInfo(String name) {
          if (!isConstructor(name)) {
              ControllerClassMetaInfo ccInfo = classInfoHolder.controllerClassMetaInfo(className);
              if (null == ccInfo) {
                  return null;
              }
              return ccInfo.handler(name);
          } else {
              return null;
          }
      }
  
      private enum _F {
          ;
  
          private static final $.Predicate<String> isController(final ControllerClassMetaInfoHolder infoSrc) {
              return new $.Predicate<String>() {
                  @Override
                  public boolean test(String s) {
                      return infoSrc.controllerClassMetaInfo(s) != null;
                  }
              };
          }
      }
  }
  