BeanUtil 对象转json

package cn.com.softmap.cache.util;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.Arrays;
import java.util.Collection;
import java.util.Date;
import java.util.Iterator;
import java.util.List;

/**
 */
public class BeanUtil {

   private static final List<?> LEAVES = Arrays.asList(Boolean.class, Character.class, Byte.class, Short.class,
         Integer.class, Long.class, Float.class, Double.class, Void.class, String.class, Date.class);

   /**
    * 把Bean转换为字符串.
    * 
    * @param obj
    * @return String
    */
   public static String toString(Object obj) {
      if (obj == null)
         return "null";

      if (LEAVES.contains(obj.getClass())) {
         return obj.toString();
      }
      if (obj instanceof Enum) {
         return ((Enum<?>) obj).name();
      }
      if (obj.getClass().isArray()) {
         Object[] oa = (Object[]) obj;
         StringBuffer sb = new StringBuffer();
         sb.append("[");
         for (int i = 0; i < oa.length; i++)
            sb.append(toString(oa[i]));
         sb.append("]");
         return sb.toString();
      }
      if (obj instanceof Collection) {
         Collection<?> tempCol = (Collection<?>) obj;
         Iterator<?> it = tempCol.iterator();
         StringBuffer sb = new StringBuffer();
         sb.append("[");
         for (int i = 0; it.hasNext(); i++) {
            if (i > 0) {
               sb.append(",");
            }
            Object val = it.next();
            sb.append(toString(val));
         }
         sb.append("]");
         return sb.toString();
      }
      if (obj instanceof Class) {
         return obj.getClass().getName();
      }
      StringBuilder sb = new StringBuilder();
      sb.append(obj.getClass().getSimpleName()).append(":[");
      for (Field f : obj.getClass().getDeclaredFields()) {
         if (Modifier.isStatic(f.getModifiers()))
            continue;
         f.setAccessible(true);
         sb.append(f.getName()).append(":");
         try {
            sb.append(toString(f.get(obj))).append(",");
         } catch (IllegalArgumentException e) {
            e.printStackTrace();
         } catch (IllegalAccessException e) {
            e.printStackTrace();
         }
      }
      sb.append("]");
      return sb.toString();
   }

   /**
    * 通过序列化进行深度复制
    * 
    * @param obj
    * @return Object
    * @throws Exception
    */
   public static Object deepClone(Object obj) throws Exception {
      return deserialize(serialize(obj));
   }

   /**
    * @param obj
    * @return byte[]
    * @throws IOException
    */
   public static byte[] serialize(Object obj) throws IOException {
      if (null == obj) {
         return null;
      }
      // 将对象写到流里
      ByteArrayOutputStream bo = new ByteArrayOutputStream();
      ObjectOutputStream oo = new ObjectOutputStream(bo);
      oo.writeObject(obj);
      oo.flush();
      return bo.toByteArray();
   }

   /**
    * @param bytes
    * @return Object
    * @throws Exception
    */
   public static Object deserialize(byte[] bytes) throws Exception {
      if (null == bytes || bytes.length == 0) {
         return null;
      }
      ByteArrayInputStream bi = new ByteArrayInputStream(bytes);
      ObjectInputStream oi = new ObjectInputStream(bi);
      return oi.readObject();
   }
}