/*

  * Copyright 2007 The Kuali Foundation

  *

  * Licensed under the Educational Community License, Version 1.0 (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.opensource.org/licenses/ecl1.php

  *

  * 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.

  */

 package org.kuali.rice.kns.uif.core;

 import org.apache.commons.lang.StringUtils;

 import org.springframework.util.MethodInvoker;

 import org.springframework.util.ReflectionUtils;

 import java.lang.reflect.Method;

 /**

  * Extends <code>MethodInvoker</code> to add properties for specifying

  * a method for invocation within the UIF

  *

  * @author Kuali Rice Team (rice.collab@kuali.org)

  */

 public class MethodInvokerConfig extends MethodInvoker {

     private String staticMethod;

     private Class[] argumentTypes;

     /**

      * Override to catch a set staticMethod since super does

      * not contain a getter

      *

      * @param staticMethod - static method to invoke

      */

     @Override

     public void setStaticMethod(String staticMethod) {

         super.setStaticMethod(staticMethod);

     }

     /**

      * Declared argument types for the method to be invoked, if not set the types will

      * be retrieved based on the target class and target name

      *

      * @return Class[] method argument types

      */

     public Class[] getArgumentTypes() {

         if (argumentTypes == null) {

             return getMethodArgumentTypes();

         }

         return argumentTypes;

     }

     /**

      * Setter for the method argument types that should be invoked

      *

      * @param argumentTypes

      */

     public void setArgumentTypes(Class[] argumentTypes) {

         this.argumentTypes = argumentTypes;

     }

     /**

      * Finds the method on the target class that matches the target name and

      * returns the declared parameter types

      *

      * @return Class[] method parameter types

      */

     protected Class[] getMethodArgumentTypes() {

         if (StringUtils.isNotBlank(staticMethod)) {

             int lastDotIndex = this.staticMethod.lastIndexOf('.');

             if (lastDotIndex == -1 || lastDotIndex == this.staticMethod.length()) {

                 throw new IllegalArgumentException("staticMethod must be a fully qualified class plus method name: " +

                         "e.g. 'example.MyExampleClass.myExampleMethod'");

             }

             String className = this.staticMethod.substring(0, lastDotIndex);

             String methodName = this.staticMethod.substring(lastDotIndex + 1);

             try {

                 setTargetClass(resolveClassName(className));

             } catch (ClassNotFoundException e) {

                 throw new RuntimeException("Unable to get class for name: " + className);

             }

             setTargetMethod(methodName);

         }

         Method[] candidates = ReflectionUtils.getAllDeclaredMethods(getTargetClass());

         for (Method candidate : candidates) {

             if (candidate.getName().equals(getTargetMethod())) {

                 return candidate.getParameterTypes();

             }

         }

         return null;

     }

 }