我有任何oracle表有时具有有效的空值是一些单元格.在SQL Developer中,它在空单元格中显示为(null).这不是问题,但在jsp页面上的网格中也显示为(null),我需要它只是空白.除非我使用空格,否则NVL不起作用.我想知道是否有一个oracle设置或某些有效的空单元格只是空白？谢谢
我正在使用尽可能少的重新编程来更新旧应用程序.我创建了一个类似于旧页面的页面,只有一些测试数据,以确保我可以创建与ejb/jpa的链接,我遇到了问题.我将发布jsp,persistence.xml和错误.在研究网络后,我仍然不明白问题是什么或如何解决它.谢谢.
JSP
<%@ page import="com.ray.adt.model.Gridmaster" %>
<jsp:useBean id="GridMasterBean" scope="page" class="com.ray.adt.ejb.grid.GridMasterBean"/>
<%
System.out.println ("Start") ;
String gridid = request.getParameter("gridid");
System.out.println ("String id is " + gridid);
Gridmaster master = null;
Integer gridInteger = Integer.parseInt(gridid);
master = GridMasterBean.findGrid(gridInteger);
String title = "None";
title = master.getProgram();
System.out.println ("title is " + title);
%>
<html>
TEST PAGE
</html>
persistence.xml中
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="1.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd">
<persistence-unit name="Grid-Persistence" transaction-type="JTA">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
<jta-data-source>java:/DefaultDS</jta-data-source>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<properties>
<property name="hibernate.transaction.factory_class" value="org.hibernate.transaction.JTATransactionFactory"/>
<property name="hibernate.hbm2ddl.auto" value="validate"/>
</properties>
</persistence-unit>
</persistence> …