计算对象大小。

 

 

package com.taobao.ju.c2b.item.manager.impl;

import com.taobao.ju.c2b.item.domain.ItemOnlineBO;

import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
import java.util.Date;


public final class SizeCalculator {
    public static int calcSize(java.io.Serializable o) {
        int ret = 0;
        class DumbOutputStream extends OutputStream {
            int count = 0;
            public void write(int b) throws IOException {
                count++; // 只计数，不产生字节转移
                }
            }
        DumbOutputStream buf = new DumbOutputStream();
        ObjectOutputStream os = null;
        try {
            os = new ObjectOutputStream(buf);
            os.writeObject(o);
            ret = buf.count;
            } catch (IOException e) {
            // No need handle this exception
            e.printStackTrace();
            ret = -1;
            } finally {
            try {
                os.close();
                } catch (Exception e) {
                }
            }
        return ret;
        }
    public static void main(String[] args){
        ItemOnlineBO itemOnlineBO = new ItemOnlineBO();
        itemOnlineBO.setActivityPrice(2012l);
        itemOnlineBO.setOriginPrice(2012l);
        itemOnlineBO.setAttributes("wewfefwewe");
        itemOnlineBO.setBuyEndTime(new Date());
        itemOnlineBO.setBuyStartTime(new Date());
        itemOnlineBO.setCategoryId(2013l);
        itemOnlineBO.setCommentary("wefwewewfe");
        itemOnlineBO.setFollowEndTime(new Date());
        itemOnlineBO.setFollowStartTime(new Date());
        itemOnlineBO.setId(2013l);
        itemOnlineBO.setItemId(2014l);
        itemOnlineBO.setStatus(10);
        itemOnlineBO.setTaobaoCategory(21001l);
        itemOnlineBO.setUserId(21451l);
        itemOnlineBO.setUmpId(5524411l);
        itemOnlineBO.setSellerId(254111l);
        System.out.println(calcSize(itemOnlineBO));
        }
}