为什么list添加的是同一个对象？各位大虾来帮帮忙！

log.info("batchAdd ");
String[] userIDs =  purchaseRecord.getUserIDs().split(",");
List<PurchaseRecord> purchaseRecordsNew = new ArrayList<PurchaseRecord>();
for(String userID:userIDs){
PurchaseRecord purchaseRecordNew = new PurchaseRecord();
purchaseRecordNew = purchaseRecord;
purchaseRecordNew.setUserID(userID.trim());
purchaseRecordNew.setCreateTime(new Date());
purchaseRecordNew.setCreateUser(authUserID);
purchaseRecordNew.setUpdateTime(purchaseRecord.getCreateTime());
purchaseRecordNew.setUpdateUser(purchaseRecord.getCreateUser());
//添加日志和短信
WardProductForm wardProductForm = new WardProductForm();
wardProductForm.setProductID(purchaseRecordNew.getProductID());
wardProductForm.setUserID(purchaseRecordNew.getUserID());
List<WardProduct> wardProducts = wardProductService.findList(wardProductForm);
Product product=productService.getEntity(purchaseRecordNew.getProductID());
String servceStatus="";
Date validDate = new Date();
if(wardProducts.size() > 0){
validDate = wardProducts.get(0).getValidDate();
servceStatus = getText("WARDPRODUCT.LOGGING.SERVICE.RECHARGE");
buildLogging(purchaseRecordNew , wardProducts.get(0).getValidDate(),product.getName(),servceStatus);
createOriginPacket(purchaseRecordNew , wardProducts.get(0).getValidDate(),product.getName(),servceStatus);
}else{
servceStatus = getText("WARDPRODUCT.LOGGING.SERVICE.PURCHASE");
buildLogging(purchaseRecordNew ,purchaseRecordNew.getCreateTime() ,product.getName(),servceStatus);
createOriginPacket(purchaseRecordNew , purchaseRecordNew.getCreateTime(),product.getName(),servceStatus);
}

int quantityValue = purchaseRecordNew.getQuantity() * purchaseRecordNew.getSalesPriceUnit();
if(purchaseRecordNew.getPriceUnit() == 1){
validDate.setDate(validDate.getDate()+purchaseRecordNew.getQuantity());
}else{
validDate.setMonth(validDate.getMonth()+quantityValue);
}
log.info("validDate = " + validDate);
purchaseRecordNew.setValidDate(validDate);
log.info("purchaseRecordNew = "+purchaseRecordNew.toString());
purchaseRecordsNew.add(purchaseRecordNew);
}
for(PurchaseRecord purchaseRecordsNews:purchaseRecordsNew){
log.info("purchaseRecordsNews = "+purchaseRecordsNews.toString());
}
this.purchaseRecordService.add(purchaseRecordsNew);
purchaseRecordID = purchaseRecord.getPurchaseRecordID();
CUDHandle(ACTION_CREATE);
return getInputName();