Spring3.0新特性

1.基础

Spring3.0对jar包进行了改变。

public class User {

private String username;

private String password;

public String getUsername() {

return username;

}

public void setUsername(String username) {

this.username = username;

}

public String getPassword() {

return password;

}

public void setPassword(String password) {

this.password = password;

}

}

public interface UserDAO {

public void save(User u);

}

public class UserDAOImpl implements UserDAO {

@Override

public void save(User u) {

System.out.println("a user saved!");

}

}

beans.xml:

《?xml version="1.0" encoding="UTF-8"?》

《beansxmlns="http://www.springframework.org/schema/beans"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://www.springframework.org/schema/beans

http://www.springframework.org/schema/beans/spring-beans-3.0.xsd"》

《bean id="userDAO"class="com.bjsxt.spring30.dao.impl.UserDAOImpl"》

《/bean》

《/beans》

@ContextConfiguration("classpath:beans.xml")

public class UserDAOTest extendsAbstractJUnit4SpringContextTests{

@Resource(name="userDAO")

private UserDAO userDAO;

@Test

public void testSave() {

this.userDAO.save(new User());

}

}

2.context.getBean可以使用泛型，不用强制类型转化啦

public class UserDAOTest2 {

@Test

public void testSave() {

ApplicationContext context = newClassPathXmlApplicationContext("beans.xml");

UserDAO userDAO = context.getBean("userDAO",UserDAO.class);//3.0

//UserDAO userDAO =(UserDAO)context.getBean("userDAO");2.5

userDAO.save(new User());

}

}

3.Bean的三种配置：xml,Annotation,javaconfig（3.0）

beans.xml:

《?xml version="1.0" encoding="UTF-8"?》

《beansxmlns="http://www.springframework.org/schema/beans"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns:context="http://www.springframework.org/schema/context"

xsi:schemaLocation="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"》

《context:component-scanbase-package="com.bjsxt.spring30.config"》《/context:component-scan》

《/beans》

com.bjsxt.spring30.config:

@Configuration

//使用这个注解需要引入cglib.jar和asm.jar

public class AppConfig {

@Bean

//默认名字userDAO

public UserDAO userDAO() {

return new UserDAOImpl();

}

//xml

//《bean id = "userDAO" class="userDAO()"

}

4.bean的注入

@Configuration

public class AppConfig {

@Bean

public UserDAO userDAO() {

return new UserDAOImpl();

}

@Bean

public UserService userService() {

UserServiceImpl service = new UserServiceImpl();

service.setUserDAO(userDAO());

return service;

}

}

public interface UserService {

public void add(User u);

}

public class UserServiceImpl implements UserService {

private UserDAO userDAO;

public UserDAO getUserDAO() {

return userDAO;

}

public void setUserDAO(UserDAO userDAO) {

this.userDAO = userDAO;

}

@Override

public void add(User u) {

this.userDAO.save(u);

}

}

@ContextConfiguration("classpath:beans.xml")

public class UserServiceTest extendsAbstractJUnit4SpringContextTests{

@Resource(name="userService")

private UserService userService;

@Test

public void testAdd() {

this.userService.add(new User());

}

}

5.SpringExpres sionLanguage表达式语言SpEL

public class SpELTest_Simple {

@Test

public void test01() {

Expr essio nParser parser = new SpelExp ressionParser();

Expre ssion exp = parser.parseExpression("'Hello,World'");

System.out.println((String)exp.getValue());

}

//如果Hello,World

@Test

public void test02() {

User u = new User();

u.setUsername("zhangsan");

EvaluationContext context = newStandardEvaluationContext(u);

Expre ssionParser parser = new SpelExpr essionParser();

Exp ression exp = parser.parseExpres sion("username");//u.getUsername()

System.out.println((String)exp.getValue(context));

System.out.println((String)exp.getValue(u));

}

//"new HelloWorld().sayHello()"

//eval_r("alert('ok');");

}

SqEL更加复杂的内容：

《!--《context:component-scanbase-package="com.bjsxt.spring30.config"》《/context:component-scan》--》

《bean id="my" class="com.bjsxt.spring30.spel.MyBean"》

《property name="randomNumber"value="#{T(java.lang.Math).random() * 100}"》《/property》

《property name="userRegion"value="#{systemProperties['user.country']}"》《/property》

《/bean》

public class MyBean {

private double randomNumber;

private String userRegion;

public double getRandomNumber() {

return randomNumber;

}

public void setRandomNumber(double randomNumber) {

this.randomNumber = randomNumber;

}

public String getUserRegion() {

return userRegion;

}

public void setUserRegion(String userRegion) {

this.userRegion = userRegion;

//System.getProperty("user.country");

}

}

@ContextConfiguration("classpath:beans.xml")

public class SpELTest extendsAbstractJUnit4SpringContextTests{

@Resource

private MyBean my;

@Test

public void test01() {

System.out.println(my.getRandomNumber());

System.out.println(my.getUserRegion());

}

}

详情见Spring3.0的开发文档