新来公司要做一个小项目，本来打算用nutz做的，结果老大让用spring jpa hibernate框架， 这里hibernate只是托管jpa而已， dao层主要还是用jpa的查询接口，而spring-data做这些系统的粘合剂，很自然mvc层用spring-mvc整合方便配置简单，页面用了bootstrap做样式和sitemesh做模块控制。
下面就谈些具体的步骤吧
我使用的maven管理项目， pom.xml 内容为
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-jpa</artifactId>
<version>1.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>3.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-hibernate3</artifactId>
<version>2.0.8</version>
<exclusions>
<exclusion>
<artifactId>hibernate</artifactId>
<groupId>org.hibernate</groupId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<scope>compile</scope>
<version>2.5</version>
</dependency>
<dependency>
<groupId>commons-dbcp</groupId>
<artifactId>commons-dbcp</artifactId>
<version>1.4</version>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.21</version>
</dependency>
<dependency>
<groupId>org.hibernate</groupId>
<artifactId>hibernate-entitymanager</artifactId>
<version>4.1.8.Final</version>
</dependency>
<dependency>
<groupId>org.sitemesh</groupId>
<artifactId>sitemesh</artifactId>
<version>3.0-alpha-1</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>java</id>
<name>java official repository</name>
<url>http://download.java.net/maven/2/</url>
</repository>
</repositories>
用到的jar包很明显有spring-mvc ,spring-data-jpa,hibernate 等，这里要注意有几个包会冲突，spring默认依赖的hibernate包版本太低，我这里手动指定了hibernate4，而且hibernate-entitymanager这个是必须的包，还有jpa这个包下载的问题， 需要添加一个源如上
下面从web.xml入手
<filter>
<filter-name>CharacterEncodingFilter</filter-name>
<filter-class>
org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
</filter>
<filter>
<filter-name>sitemesh</filter-name>
<filter-class>cn.mucang.offlineModule.filters.MetaSitemeshFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>CharacterEncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<!-- Processes application requests -->
<servlet>
<servlet-name>mvc-dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/applicationContext.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>mvc-dispatcher</servlet-name>
<url-pattern>*.do</url-pattern>
</servlet-mapping>
<filter-mapping>
<filter-name>sitemesh</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>FORWARD</dispatcher>
<dispatcher>REQUEST</dispatcher>
</filter-mapping>
这里配置了 编码防止接收的内容出现乱码问题，还有spring-mvc的入口servlet，还有就是 sitemesh了，这个要放到spring-mvc后面，它只需要拦截mvc 转发的jsp请求即可
下面介绍一下包结构：
src下： your.company.package.domains 领域类，
.dao 领域类操作接口
.controllers 控制器
.services 服务层， 方法上可使用 事务注解
.utils 工具类
.filters 这个包看情况添加吧，这里我把自定义了 MetaSitemeshFilter
webapp下 css/ ,js/ ,img/， WEB-INF/templates/ 布局文件， WEB-INF/views/ 视图
下面是最重要的applicationContext.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:jpa="http://www.springframework.org/schema/data/jpa"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="
http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/data/jpa http://www.springframework.org/schema/data/jpa/spring-jpa.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-3.1.xsd">
<!-- DispatcherServlet Context: defines this servlet's request-processing infrastructure -->
<!-- Scans within the base package of the application for @Components to configure as beans -->
<!-- @Controller, @Service, @Configuration, etc. -->
<context:component-scan base-package="cn.mucang.offlineModule" />
<!-- Enables the Spring MVC @Controller programming model -->
<mvc:annotation-driven />
<context:annotation-config />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix">
<value>/WEB-INF/views/</value>
</property>
<property name="suffix">
<value>.jsp</value>
</property>
</bean>
<!-- spring mvc end -->
<!-- spring jpa start-->
<bean id="dataSource"
class="org.apache.commons.dbcp.BasicDataSource">
<property name="username" value="root" />
<property name="password" value="000000" />
<property name="driverClassName" value="com.mysql.jdbc.Driver" />
<property name="url" value="jdbc:mysql://localhost/offline" />
</bean>
<bean id="entityManagerFactory"
class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
<!-- <property name="persistenceUnitName" value="coreJpa" /> -->
<property name="dataSource" ref="dataSource" />
<property name="jpaVendorAdapter">
<bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
<property name="database" value="MYSQL"/>
<property name="showSql" value="true"/>
<property name="generateDdl" value="true" />
</bean>
</property>
<property name="jpaProperties">
<props>
<prop key="hibernate.max_fetch_depth" >3</prop>
<!--自动输出schema创建DDL语句 -->
<prop key="hibernate.hbm2ddl.auto" >update</prop>
<prop key="hibernate.show_sql" >true</prop>
<prop key="hibernate.format_sql" >true</prop>
<prop key="javax.persistence.validation.mode" >none </prop>
</props>
</property>
</bean>
<jpa:repositories base-package="cn.mucang.offlineModule.dao" query-lookup-strategy="create-if-not-found" />
<!-- TX Manager -->
<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
<property name="entityManagerFactory" ref="entityManagerFactory" />
</bean>
<tx:annotation-driven/>
<!-- spring jpa end -->
这里主要配置了 mvc 注解方式和 视图的简化， 还有datasource 和 spring+jpa+hibernate的结合情况，最后添加注解事务控制
这里我配置 hibernate.hbm2ddl.auto=create ，按说明应该是可以生成表结构的，但我测试时没有生成，控制台也没报错，ddl的sql都打印了，初步判断是事务引起的，这个框架中我没有测试事务，多表联合查询也研究，这些我想跟这个配置应该关系不大了，读者有需求去google吧
对了这里还用到了一个hibernate的配置文件 persistence.xml, 放在 src下 META-INF下，
这里面什么内容也没有， 也有种方式是把数据源的配置放到这个文件中，感觉这样配置就太零散了，这个文件中就是空的，但是没有这个文件的话启动会报错
文件内容
<?xml version="1.0" encoding="UTF-8"?>
<persistence xmlns="http://java.sun.com/xml/ns/persistence" version="1.0">
<persistence-unit name="Teste" transaction-type="RESOURCE_LOCAL">
<provider>org.hibernate.ejb.HibernatePersistence</provider>
</persistence-unit>
</persistence>
基本上所有的配置就完了，
下面挨个放出java代码就行
controllers下 HelloController.java文件
@Controller
public class HelloController {
@Autowired
private RuleDao ruleDao;
@RequestMapping("/hello")
public String hello(Model model){
model.addAttribute("count", ruleDao.count());
return "hello";
}
}
domains下 Rule.java 文件
@Entity
@Table(name="rule")
public class Rule {
@Id
private Integer id;
@Column(length=100,name="para_key")
private String key;
@Column(length=100,name="para_value")
private String value;
@Column(length=10)
private String operator;
@Column(name="empty_key")
private Boolean emptyKey ;
@Column(name="empty_value")
private Boolean emptyValue;
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public String getKey() {
return key;
}
public void setKey(String key) {
this.key = key;
}
public String getValue() {
return value;
}
public void setValue(String value) {
this.value = value;
}
public String getOperator() {
return operator;
}
public void setOperator(String operator) {
this.operator = operator;
}
public Boolean getEmptyKey() {
return emptyKey;
}
public void setEmptyKey(Boolean emptyKey) {
this.emptyKey = emptyKey;
}
public Boolean getEmptyValue() {
return emptyValue;
}
public void setEmptyValue(Boolean emptyValue) {
this.emptyValue = emptyValue;
}
}
这个文件中没有@id的话也会报错，表中必须存在主键
dao中 RuleDao.java
public interface RuleDao extends CrudRepository<Rule, Integer>{
}
这里只需要实现接口即可，简单查询按规则生成方法名就行，复杂的请用@Query或者@NamedQuery进行手动sq查询 到这里基本上就快完工了，再把页面写一下就ok了， 记得在数据库中添加rule表
映射的url为 /hello.do, 输入的视图为 WEB-INF/views/hello.jsp,内容如下：
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<html>
<head>
<title>Insert title here</title>
<meta name="layout" content="main">
</head>
<body>
<h2>h3llo ${count}</h2>
</body>
</html>
这里就用到了metasitemeshfilter 代码如下
public class MetaSitemeshFilter extends ConfigurableSiteMeshFilter{
private final String DECORATOR_PREFIX = "/WEB-INF/templates/";
private final String DECORATOR_SUFFIX = ".jsp";
@Override
protected void applyCustomConfiguration(SiteMeshFilterBuilder builder) {
super.applyCustomConfiguration(builder);
builder.setCustomDecoratorSelector(new DecoratorSelector<WebAppContext>() {
@Override
public String[] selectDecoratorPaths(Content content,
WebAppContext context) throws IOException {
String decoratorPath = content.getExtractedProperties()
.getChild("meta").getChild("layout").getValue();
if (decoratorPath == null || decoratorPath.trim().equals(""))
return new String[] {};
else
return new String[] { DECORATOR_PREFIX + decoratorPath.trim()
+ DECORATOR_SUFFIX };
}
});
}
可以看出把会取得jsp中的meta layout的值，然后做为布局文件进行渲染，
因此还要在WEB-INF/templates/下添加main.jsp，这里就很简单了
<div><sitemesh:write property="body"/>
</div>
<footer> bottom copyright</footer>
</body>
</html><html>
<head>
<title ><sitemesh:write property="title"/>- my company</title>
<sitemesh:write property="head"/>
</head>
<body>
<h2>top</h2>
然后访问 项目打包放到tomcat中，启动tomcat即可。访问 127.0.0.1:port/appname/hello.do
然后就看到了 top hell2 0 bottom这些任容吧，如果有问题欢迎发邮件。 所有的代码就是这样了