JAVA将非空值附于别一个对象

import java.beans.PropertyDescriptor;
import java.lang.reflect.InvocationTargetException;
import java.util.Iterator;
import java.util.Map;

import org.apache.commons.beanutils.BeanUtilsBean;
import org.apache.commons.beanutils.DynaBean;
import org.apache.commons.beanutils.DynaProperty;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
 
 public class BeanUtil
 {
   private static Log log = LogFactory.getLog(BeanUtil.class);
 
   public static void copyNotNullProperties(Object dest, Object orig)
     throws IllegalAccessException, InvocationTargetException
   {
     BeanUtilsBean beanUtils = BeanUtilsBean.getInstance();
 
     if (dest == null) {
       throw new IllegalArgumentException("No destination bean specified");
     }
     if (orig == null) {
       throw new IllegalArgumentException("No origin bean specified");
     }
     if (log.isDebugEnabled()) {
       log.debug("BeanUtils.copyProperties(" + dest + ", " + orig + ")");
     }
 
     if ((orig instanceof DynaBean)) {
       DynaProperty[] origDescriptors = ((DynaBean)orig).getDynaClass()
         .getDynaProperties();
       for (int i = 0; i < origDescriptors.length; i++) {
         String name = origDescriptors[i].getName();
 
         if ((!beanUtils.getPropertyUtils().isReadable(orig, name)) || 
           (!beanUtils.getPropertyUtils().isWriteable(dest, name))) continue;
         Object value = ((DynaBean)orig).get(name);
         beanUtils.copyProperty(dest, name, value);
       }
     }
     else if ((orig instanceof Map)) {
       Iterator entries = ((Map)orig).entrySet().iterator();
       while (entries.hasNext()) {
         Map.Entry entry = (Map.Entry)entries.next();
         String name = (String)entry.getKey();
         if (beanUtils.getPropertyUtils().isWriteable(dest, name))
           beanUtils.copyProperty(dest, name, entry.getValue());
       }
     }
     else {
       PropertyDescriptor[] origDescriptors = beanUtils.getPropertyUtils()
         .getPropertyDescriptors(orig);
       for (int i = 0; i < origDescriptors.length; i++) {
         String name = origDescriptors[i].getName();
         if ("class".equals(name)) {
           continue;
         }
         if ((!beanUtils.getPropertyUtils().isReadable(orig, name)) || 
           (!beanUtils.getPropertyUtils().isWriteable(dest, name))) continue;
         try {
           Object value = beanUtils.getPropertyUtils().getSimpleProperty(orig, name);
           if (value != null)
             beanUtils.copyProperty(dest, name, value);
         }
         catch (NoSuchMethodException localNoSuchMethodException)
         {
         }
       }
     }
   }
 }