使用映射，主要就是方法映射，只要传过来的字段和你的pojo对象里面的字段一样，就可以set这个字段。/**

• Copyright (c) 2011-2015, James Zhan 詹波 (jfinal@126.com). *
• 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.jfinal.core;

import java.lang.reflect.Method;
import java.util.Map;
import java.util.Map.Entry;
import javax.servlet.http.HttpServletRequest;
import com.jfinal.kit.StrKit;
import com.jfinal.plugin.activerecord.ActiveRecordException;
import com.jfinal.plugin.activerecord.Model;
import com.jfinal.plugin.activerecord.Table;
import com.jfinal.plugin.activerecord.TableMapping;

/**

• ModelInjector
  */
  final class ModelInjector {

  @SuppressWarnings("unchecked")
  public static T inject(Class<?> modelClass, HttpServletRequest request, boolean skipConvertError) {
  String modelName = modelClass.getSimpleName();
  return (T)inject(modelClass, StrKit.firstCharToLowerCase(modelName), request, skipConvertError);
  }

  @SuppressWarnings({ "rawtypes", "unchecked" })
  public static final T inject(Class<?> modelClass, String modelName, HttpServletRequest request, boolean skipConvertError) {
  Object model = null;
  try {
  model = modelClass.newInstance();
  } catch (Exception e) {
  throw new RuntimeException(e);
  }

  if (model instanceof Model)
      injectActiveRecordModel((Model)model, modelName, request, skipConvertError);
  else
      injectCommonModel(model, modelName, request, modelClass, skipConvertError);
  
  return (T)model;
  

  }

  private static final void injectCommonModel(Object model, String modelName, HttpServletRequest request, Class<?> modelClass, boolean skipConvertError) {
  Method[] methods = modelClass.getMethods();
  for (Method method : methods) {
  String methodName = method.getName();
  if (methodName.startsWith("set") == false) // only setter method
  continue;

      Class<?>[] types = method.getParameterTypes();
      if (types.length != 1)                      // only one parameter
          continue;
  
      String attrName = methodName.substring(3);
      String value = request.getParameter(modelName + "." + StrKit.firstCharToLowerCase(attrName));
      if (value != null) {
          try {
              method.invoke(model, TypeConverter.convert(types[0], value));
          } catch (Exception e) {
              if (skipConvertError == false)
              throw new RuntimeException(e);
          }
      }
  }
  

  }

  @SuppressWarnings("rawtypes")
  private static final void injectActiveRecordModel(Model<?> model, String modelName, HttpServletRequest request, boolean skipConvertError) {
  Table table = TableMapping.me().getTable(model.getClass());

  String modelNameAndDot = modelName + ".";
  
  Map<String, String[]> parasMap = request.getParameterMap();
  for (Entry<String, String[]> e : parasMap.entrySet()) {
      String paraKey = e.getKey();
      if (paraKey.startsWith(modelNameAndDot)) {
          String paraName = paraKey.substring(modelNameAndDot.length());
          Class colType = table.getColumnType(paraName);
          if (colType == null)
              throw new ActiveRecordException("The model attribute " + paraKey + " is not exists.");
          String[] paraValue = e.getValue();
          try {
              // Object value = Converter.convert(colType, paraValue != null ? paraValue[0] : null);
              Object value = paraValue[0] != null ? TypeConverter.convert(colType, paraValue[0]) : null;
              model.set(paraName, value);
          } catch (Exception ex) {
              if (skipConvertError == false)
                  throw new RuntimeException("Can not convert parameter: " + modelNameAndDot + paraName, ex);
          }
      }
  }
  

  }
  }

springMVC @RequestBody
介绍：http://snowolf.iteye.com/blog/1628861