JavaBean和Map转换封装类详解编程语言

package com.ljq.util; 
 
import java.beans.BeanInfo; 
import java.beans.Introspector; 
import java.beans.PropertyDescriptor; 
import java.lang.reflect.Method; 
import java.util.ArrayList; 
import java.util.HashMap; 
import java.util.List; 
import java.util.Map; 
 
 
/** 
 * Map工具类 
 * 
 * @author jqlin 
 */ 
public class MapUtils { 
 
    /** 
     * 从map集合中获取属性值 
     *  
     * @param <E> 
     * @param map 
     *            map集合 
     * @param key 
     *            键对 
     * @param defaultValue 
     *            默认值 
     * @return 
     * @author jiqinlin 
     */ 
    @SuppressWarnings({ "unchecked", "rawtypes" }) 
    public final static <E> E get(Map map, Object key, E defaultValue) { 
        Object o = map.get(key); 
        if (o == null) 
            return defaultValue; 
        return (E) o; 
    } 
     
    /** 
     * Map集合对象转化成 JavaBean集合对象 
     *  
     * @param javaBean JavaBean实例对象 
     * @param mapList Map数据集对象 
     * @return 
     * @author jqlin 
     */ 
    @SuppressWarnings({ "rawtypes" }) 
    public static <T> List<T> map2Java(T javaBean, List<Map> mapList) { 
        if(mapList == null || mapList.isEmpty()){ 
            return null; 
        } 
        List<T> objectList = new ArrayList<T>(); 
         
        T object = null; 
        for(Map map : mapList){ 
            if(map != null){ 
                object = map2Java(javaBean, map); 
                objectList.add(object); 
            } 
        } 
         
        return objectList; 
         
    } 
     
    /** 
     * Map对象转化成 JavaBean对象 
     *  
     * @param javaBean JavaBean实例对象 
     * @param map Map对象 
     * @return 
     * @author jqlin 
     */ 
    @SuppressWarnings({ "rawtypes","unchecked", "hiding" }) 
    public static <T> T map2Java(T javaBean, Map map) { 
        try { 
            // 获取javaBean属性 
            BeanInfo beanInfo = Introspector.getBeanInfo(javaBean.getClass()); 
            // 创建 JavaBean 对象 
            Object obj = javaBean.getClass().newInstance(); 
 
            PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors(); 
            if (propertyDescriptors != null && propertyDescriptors.length > 0) { 
                String propertyName = null; // javaBean属性名 
                Object propertyValue = null; // javaBean属性值 
                for (PropertyDescriptor pd : propertyDescriptors) { 
                    propertyName = pd.getName(); 
                    if (map.containsKey(propertyName)) { 
                        propertyValue = map.get(propertyName); 
                        pd.getWriteMethod().invoke(obj, new Object[] { propertyValue }); 
                    } 
                } 
                return (T) obj; 
            } 
        } catch (Exception e) { 
            e.printStackTrace(); 
        } 
 
        return null; 
    } 
 
    /** 
     * JavaBean对象转化成Map对象 
     *  
     * @param javaBean 
     * @return 
     * @author jqlin 
     */ 
    @SuppressWarnings({ "rawtypes", "unchecked" }) 
    public static Map java2Map(Object javaBean) { 
        Map map = new HashMap(); 
          
        try { 
            // 获取javaBean属性 
            BeanInfo beanInfo = Introspector.getBeanInfo(javaBean.getClass()); 
 
            PropertyDescriptor[] propertyDescriptors = beanInfo.getPropertyDescriptors(); 
            if (propertyDescriptors != null && propertyDescriptors.length > 0) { 
                String propertyName = null; // javaBean属性名 
                Object propertyValue = null; // javaBean属性值 
                for (PropertyDescriptor pd : propertyDescriptors) { 
                    propertyName = pd.getName(); 
                    if (!propertyName.equals("class")) { 
                        Method readMethod = pd.getReadMethod(); 
                        propertyValue = readMethod.invoke(javaBean, new Object[0]); 
                        map.put(propertyName, propertyValue); 
                    } 
                } 
            } 
             
        } catch (Exception e) { 
            e.printStackTrace(); 
        }   
         
        return map; 
    } 
  
}