zhangzhen0104的专栏

1.导包(这里省略)2.环境搭建方法一：数据源配置在persistence.xml中    persistence.xml(位于META-INF下)<?xml version="1.0" encoding="UTF-8"?><persistence xmlns="http://java.sun.com/xml/ns/persistence" xmlns...

ns="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" ver