accessplanfactory.java

本套系统采用了业界当前最为流行的beanAction组件

/*
 *  Copyright 2004 Clinton Begin
 *
 *  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.
 */
package com.ibatis.sqlmap.engine.accessplan;

import java.util.Map;

/**
 * Factory to get an accesss plan appropriate for an object
 */
public class AccessPlanFactory {

  private static boolean bytecodeEnhancementEnabled = false;

  private AccessPlanFactory() {
  }

  /**
   * Creates an access plan for working with a bean
   *
   * @param clazz
   * @param propertyNames
   * @return An access plan
   */
  public static AccessPlan getAccessPlan(Class clazz, String[] propertyNames) {
    AccessPlan plan;

    boolean complex = false;

    if (clazz == null || propertyNames == null) {
      complex = true;
    } else {
      for (int i = 0; i < propertyNames.length; i++) {
        if (propertyNames[i].indexOf('[') > -1
            || propertyNames[i].indexOf('.') > -1) {
          complex = true;
          break;
        }
      }
    }

    if (complex) {
      plan = new ComplexAccessPlan(clazz, propertyNames);
    } else if (Map.class.isAssignableFrom(clazz)) {
      plan = new MapAccessPlan(clazz, propertyNames);
    } else {
      // Possibly causes bug 945746 --but the bug is unconfirmed (can't be reproduced)
      if (bytecodeEnhancementEnabled) {
        try {
          plan = new EnhancedPropertyAccessPlan(clazz, propertyNames);
        } catch (Throwable t) {
          try {
            plan = new PropertyAccessPlan(clazz, propertyNames);
          } catch (Throwable t2) {
            plan = new ComplexAccessPlan(clazz, propertyNames);
          }
        }
      } else {
        try {
          plan = new PropertyAccessPlan(clazz, propertyNames);
        } catch (Throwable t) {
          plan = new ComplexAccessPlan(clazz, propertyNames);
        }
      }
    }
    return plan;
  }

  /**
   * Tells whether or not bytecode enhancement (CGLIB, etc) is enabled
   *
   * @return true if bytecode enhancement is enabled
   */
  public static boolean isBytecodeEnhancementEnabled() {
    return bytecodeEnhancementEnabled;
  }

  /**
   * Turns on or off bytecode enhancement (CGLIB, etc)
   *
   * @param bytecodeEnhancementEnabled - the switch
   */
  public static void setBytecodeEnhancementEnabled(boolean bytecodeEnhancementEnabled) {
    AccessPlanFactory.bytecodeEnhancementEnabled = bytecodeEnhancementEnabled;
  }

}