Java单元测试之模拟利器(2):Powermock在Spring测试的应用

本部分先对spring做简单介绍,然后介绍mockito和powermock在spring测试中的应用。

此部分需要准备的软件:

基于JDK 7或以上版本

Eclipse   http://www.oracle.com/technetwork/java/javase/downloads/index.html
Mockito    http://mockito.org/
Spring     http://maven.springframework.org/release/org/springframework/spring/

Spring简介

Spring是Java的开源企业应用程序开发框架,它为 Java beans控制容器的翻转。最初由Rod Johnson在2003年6月基于Apache2.0许可证发布。
Spring框架处理底层,使我们能够专注于应用程序逻辑。 Spring能够从POJOs(Plain Old Java Objects)非侵入式的构建应用程序。比如:
•不需要处理servlet或servlet API,Java方法可以处理HTTP POST / GET请求。
•不需要处理web服务API,Java方法可提供RESTful Web服务
•不需要处理事务API,Java方法可以执行数据库事务
•不需要处理远程API,本地Java方法使用RPC(remote procedure call)
•不需要处理JMS API,Java方法可以使用和处理消息
•不需要处理JMX API,Java方法可以作为管理扩展

Spring的特性:
•开源应用程序框架
•企业轻量级应用框架
•非侵入性(基于POJO)
•模块化
•可扩展用于其他框架
•Java企业应用程序的事实标准

优势:
•使用POJO、轻,非入侵
•通过依赖注入和接口定向实现松耦合
•通过aspect和共同约定实现声明式编程
•通过aspect和模板减少代码

Spring Framework的核心容器:

•  Core and Beans:提供IOC(Inversion of control)和DI(dependency injection)

• Context:类似JNDI(Java Naming and Directory Interface,Java命名和目录接口),用于在框架中访问对象。

• 表示语言(Expression Language):SpEL,用于查询和修改对象图并评估数学表达式。

AOP模块
AOP是Spring面向方面编程的实现。它解耦业务逻辑和日志、安全等基础代码。

instrumentation模块
提供instrumentation类支持,通过MBean展示容器资源和帮助JMX管理。

消息模块
包含Spring Integration项目的关键抽象如Message、MessageChannel和的MessageHandler。

数据访问模块
•JDBC:JDBC抽象层
•ORM:为流行的对象关系映射提供集成层API,包括JPA,JDO,Hibernate和iBATIS
•OXM:对象/ XML映射抽象层,实现了JAXB,Castor,XMLBeans的,JiBX和Xstream

•JMS:生产和消费消息
•事务:它支持programmatic和programmatic事务管理

web层
该网络层包括web,webmvc / servlet中,WebSocket和webmvc-portlet模块:

•Web:文件上传等基础组件。
•Webmvc:
•Portlet
•WebSocket

Spring项目涉及安全配置、Web应用程序、大数据、LDAP等。 Spring框架是其中一部分。
JNDI(Java Naming and Directory Interface,Java命名和目录接口)

Java相关的一些博客:

http://www.gualtierotesta.it/

IoC(Inversion of Control)和DI(dependency injection)经常不区分使用。IoC由IoC实现。

两种类型的依赖注入:

•  Constructor injection

•  Setter injection

比如定义:

<bean id="bookLister" class="com.packt.di.BookLister">
<constructor-arg ref="bookService"/>
</bean>
<bean id="bookService" class="com.packt.di.BookServiceImpl" />

等同于:

BookService service = new BookServiceImpl();
BookLister bookLister = new BookLister(service);
<bean id="bookListerSetterInjection" class="com.packt.di.BookLister">
<property name="bookService" ref="bookService" />
</bean>
<bean id="bookService" class="com.packt.di.BookServiceImpl" />

等同于:

BookService service = new BookServiceImpl();
BookLister bookLister = new BookLister();
bookLister.setBookService(service);

Spring IoC container 即ApplicationContext。管理的容器叫bean,比如bookService就是bean,即Spring IoC container管理的对象。

bean的属性有:

class、name(即id)、scope、constructor-arg、properties、lazy-init(使用时才创建容器)、init-method 、destroy-method。

scope的取值有:

  • singleton:每个bean实例一个容器。实际上是每个bean实例一个classloader。
  • prototype:每个bean实例多个实例对象。
  • request:每个bean实例一个HTTP request。
  • session:每个bean实例一个HTTP session。
  • global-session:每个bean实例一个全局HTTP session。

生命周期:

第一个实例

前提: Maven和STS安装OK,都可以从Eclipse 市场安装。

新建Spring Starter Project项目,

Name:SpringOverview 注明名字前后不要有空格。

Type:Maven

其他用默认配置。

原有默认的SpringOverviewApplication类内容如下:

package com.example;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class SpringOverviewApplication {

    public static void main(String[] args) {
        SpringApplication.run(SpringOverviewApplication.class, args);
    }
}

删除包com.example下面的SpringOverviewApplication类。新建HelloWorld类:

package com.example;

public class HelloWorld {

    private String message;

    public String getMessage() {
        return message;
    }

    public void setMessage(String message) {
        this.message = message;
    }
}

在src/main/resources新建 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"
xsi:schemaLocation="http://www.springframework.org/schema/beans

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

    <bean id="helloWorld" class="com.example.HelloWorld">
        <property name="message" value="Welcome to the Spring world">
        </property>
    </bean>
</beans>

com.example下面新建类HelloWorldExample:

package com.example;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class HelloWorldExample {

    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        HelloWorld world = (HelloWorld)
        context.getBean("helloWorld");
        System.out.println(world.getMessage());
        }
}

用Spring Boot App的方式执行:

11:38:15.765 [main] DEBUG o.s.core.env.StandardEnvironment - Adding [systemProperties] PropertySource with lowest search precedence
11:38:15.768 [main] DEBUG o.s.core.env.StandardEnvironment - Adding [systemEnvironment] PropertySource with lowest search precedence
11:38:15.768 [main] DEBUG o.s.core.env.StandardEnvironment - Initialized StandardEnvironment with PropertySources [systemProperties,systemEnvironment]
11:38:15.770 [main] INFO  o.s.c.s.ClassPathXmlApplicationContext - Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@71c7db30: startup date [Thu Dec 31 11:38:15 CST 2015]; root of context hierarchy
11:38:15.794 [main] DEBUG o.s.core.env.StandardEnvironment - Adding [systemProperties] PropertySource with lowest search precedence
11:38:15.795 [main] DEBUG o.s.core.env.StandardEnvironment - Adding [systemEnvironment] PropertySource with lowest search precedence
11:38:15.795 [main] DEBUG o.s.core.env.StandardEnvironment - Initialized StandardEnvironment with PropertySources [systemProperties,systemEnvironment]
11:38:15.801 [main] INFO  o.s.b.f.xml.XmlBeanDefinitionReader - Loading XML bean definitions from class path resource [applicationContext.xml]
11:38:15.811 [main] DEBUG o.s.b.f.xml.DefaultDocumentLoader - Using JAXP provider [com.sun.org.apache.xerces.internal.jaxp.DocumentBuilderFactoryImpl]
11:38:15.830 [main] DEBUG o.s.b.f.xml.PluggableSchemaResolver - Loading schema mappings from [META-INF/spring.schemas]
11:38:15.833 [main] DEBUG o.s.b.f.xml.PluggableSchemaResolver - Loaded schema mappings: {http://www.springframework.org/schema/cache/spring-cache-4.2.xsd=org/springframework/cache/config/spring-cache-4.2.xsd, http://www.springframework.org/schema/aop/spring-aop-4.1.xsd=org/springframework/aop/config/spring-aop-4.1.xsd, http://www.springframework.org/schema/context/spring-context-3.1.xsd=org/springframework/context/config/spring-context-3.1.xsd, http://www.springframework.org/schema/util/spring-util-3.0.xsd=org/springframework/beans/factory/xml/spring-util-3.0.xsd, http://www.springframework.org/schema/tool/spring-tool.xsd=org/springframework/beans/factory/xml/spring-tool-4.2.xsd, http://www.springframework.org/schema/aop/spring-aop-3.2.xsd=org/springframework/aop/config/spring-aop-3.2.xsd, http://www.springframework.org/schema/lang/spring-lang-4.1.xsd=org/springframework/scripting/config/spring-lang-4.1.xsd, http://www.springframework.org/schema/context/spring-context-4.0.xsd=org/springframework/context/config/spring-context-4.0.xsd, http://www.springframework.org/schema/beans/spring-beans-4.2.xsd=org/springframework/beans/factory/xml/spring-beans-4.2.xsd, http://www.springframework.org/schema/tool/spring-tool-4.1.xsd=org/springframework/beans/factory/xml/spring-tool-4.1.xsd, http://www.springframework.org/schema/lang/spring-lang-3.2.xsd=org/springframework/scripting/config/spring-lang-3.2.xsd, http://www.springframework.org/schema/cache/spring-cache-3.2.xsd=org/springframework/cache/config/spring-cache-3.2.xsd, http://www.springframework.org/schema/jee/spring-jee-4.1.xsd=org/springframework/ejb/config/spring-jee-4.1.xsd, http://www.springframework.org/schema/util/spring-util-2.0.xsd=org/springframework/beans/factory/xml/spring-util-2.0.xsd, http://www.springframework.org/schema/task/spring-task-4.2.xsd=org/springframework/scheduling/config/spring-task-4.2.xsd, http://www.springframework.org/schema/tool/spring-tool-3.2.xsd=org/springframework/beans/factory/xml/spring-tool-3.2.xsd, http://www.springframework.org/schema/context/spring-context.xsd=org/springframework/context/config/spring-context-4.2.xsd, http://www.springframework.org/schema/cache/spring-cache-4.1.xsd=org/springframework/cache/config/spring-cache-4.1.xsd, http://www.springframework.org/schema/aop/spring-aop-4.0.xsd=org/springframework/aop/config/spring-aop-4.0.xsd, http://www.springframework.org/schema/jee/spring-jee-3.2.xsd=org/springframework/ejb/config/spring-jee-3.2.xsd, http://www.springframework.org/schema/context/spring-context-3.0.xsd=org/springframework/context/config/spring-context-3.0.xsd, http://www.springframework.org/schema/util/spring-util-2.5.xsd=org/springframework/beans/factory/xml/spring-util-2.5.xsd, http://www.springframework.org/schema/beans/spring-beans-3.2.xsd=org/springframework/beans/factory/xml/spring-beans-3.2.xsd, http://www.springframework.org/schema/aop/spring-aop-3.1.xsd=org/springframework/aop/config/spring-aop-3.1.xsd, http://www.springframework.org/schema/lang/spring-lang-4.0.xsd=org/springframework/scripting/config/spring-lang-4.0.xsd, http://www.springframework.org/schema/beans/spring-beans-4.1.xsd=org/springframework/beans/factory/xml/spring-beans-4.1.xsd, http://www.springframework.org/schema/tool/spring-tool-4.0.xsd=org/springframework/beans/factory/xml/spring-tool-4.0.xsd, http://www.springframework.org/schema/lang/spring-lang-3.1.xsd=org/springframework/scripting/config/spring-lang-3.1.xsd, http://www.springframework.org/schema/cache/spring-cache-3.1.xsd=org/springframework/cache/config/spring-cache-3.1.xsd, http://www.springframework.org/schema/jee/spring-jee-4.0.xsd=org/springframework/ejb/config/spring-jee-4.0.xsd, http://www.springframework.org/schema/task/spring-task-4.1.xsd=org/springframework/scheduling/config/spring-task-4.1.xsd, http://www.springframework.org/schema/tool/spring-tool-3.1.xsd=org/springframework/beans/factory/xml/spring-tool-3.1.xsd, http://www.springframework.org/schema/cache/spring-cache-4.0.xsd=org/springframework/cache/config/spring-cache-4.0.xsd, http://www.springframework.org/schema/jee/spring-jee-3.1.xsd=org/springframework/ejb/config/spring-jee-3.1.xsd, http://www.springframework.org/schema/util/spring-util-4.2.xsd=org/springframework/beans/factory/xml/spring-util-4.2.xsd, http://www.springframework.org/schema/task/spring-task-3.2.xsd=org/springframework/scheduling/config/spring-task-3.2.xsd, http://www.springframework.org/schema/beans/spring-beans-3.1.xsd=org/springframework/beans/factory/xml/spring-beans-3.1.xsd, http://www.springframework.org/schema/util/spring-util.xsd=org/springframework/beans/factory/xml/spring-util-4.2.xsd, http://www.springframework.org/schema/aop/spring-aop-3.0.xsd=org/springframework/aop/config/spring-aop-3.0.xsd, http://www.springframework.org/schema/beans/spring-beans-4.0.xsd=org/springframework/beans/factory/xml/spring-beans-4.0.xsd, http://www.springframework.org/schema/beans/spring-beans.xsd=org/springframework/beans/factory/xml/spring-beans-4.2.xsd, http://www.springframework.org/schema/lang/spring-lang-3.0.xsd=org/springframework/scripting/config/spring-lang-3.0.xsd, http://www.springframework.org/schema/context/spring-context-2.5.xsd=org/springframework/context/config/spring-context-2.5.xsd, http://www.springframework.org/schema/task/spring-task-4.0.xsd=org/springframework/scheduling/config/spring-task-4.0.xsd, http://www.springframework.org/schema/tool/spring-tool-3.0.xsd=org/springframework/beans/factory/xml/spring-tool-3.0.xsd, http://www.springframework.org/schema/aop/spring-aop-2.0.xsd=org/springframework/aop/config/spring-aop-2.0.xsd, http://www.springframework.org/schema/jee/spring-jee-3.0.xsd=org/springframework/ejb/config/spring-jee-3.0.xsd, http://www.springframework.org/schema/util/spring-util-4.1.xsd=org/springframework/beans/factory/xml/spring-util-4.1.xsd, http://www.springframework.org/schema/task/spring-task-3.1.xsd=org/springframework/scheduling/config/spring-task-3.1.xsd, http://www.springframework.org/schema/beans/spring-beans-3.0.xsd=org/springframework/beans/factory/xml/spring-beans-3.0.xsd, http://www.springframework.org/schema/jee/spring-jee.xsd=org/springframework/ejb/config/spring-jee-4.2.xsd, http://www.springframework.org/schema/aop/spring-aop-2.5.xsd=org/springframework/aop/config/spring-aop-2.5.xsd, http://www.springframework.org/schema/lang/spring-lang-2.0.xsd=org/springframework/scripting/config/spring-lang-2.0.xsd, http://www.springframework.org/schema/util/spring-util-3.2.xsd=org/springframework/beans/factory/xml/spring-util-3.2.xsd, http://www.springframework.org/schema/task/spring-task.xsd=org/springframework/scheduling/config/spring-task-4.2.xsd, http://www.springframework.org/schema/tool/spring-tool-2.0.xsd=org/springframework/beans/factory/xml/spring-tool-2.0.xsd, http://www.springframework.org/schema/lang/spring-lang-2.5.xsd=org/springframework/scripting/config/spring-lang-2.5.xsd, http://www.springframework.org/schema/context/spring-context-4.2.xsd=org/springframework/context/config/spring-context-4.2.xsd, http://www.springframework.org/schema/jee/spring-jee-2.0.xsd=org/springframework/ejb/config/spring-jee-2.0.xsd, http://www.springframework.org/schema/tool/spring-tool-2.5.xsd=org/springframework/beans/factory/xml/spring-tool-2.5.xsd, http://www.springframework.org/schema/jee/spring-jee-2.5.xsd=org/springframework/ejb/config/spring-jee-2.5.xsd, http://www.springframework.org/schema/util/spring-util-4.0.xsd=org/springframework/beans/factory/xml/spring-util-4.0.xsd, http://www.springframework.org/schema/task/spring-task-3.0.xsd=org/springframework/scheduling/config/spring-task-3.0.xsd, http://www.springframework.org/schema/aop/spring-aop-4.2.xsd=org/springframework/aop/config/spring-aop-4.2.xsd, http://www.springframework.org/schema/lang/spring-lang.xsd=org/springframework/scripting/config/spring-lang-4.2.xsd, http://www.springframework.org/schema/context/spring-context-3.2.xsd=org/springframework/context/config/spring-context-3.2.xsd, http://www.springframework.org/schema/util/spring-util-3.1.xsd=org/springframework/beans/factory/xml/spring-util-3.1.xsd, http://www.springframework.org/schema/beans/spring-beans-2.0.xsd=org/springframework/beans/factory/xml/spring-beans-2.0.xsd, http://www.springframework.org/schema/cache/spring-cache.xsd=org/springframework/cache/config/spring-cache-4.2.xsd, http://www.springframework.org/schema/lang/spring-lang-4.2.xsd=org/springframework/scripting/config/spring-lang-4.2.xsd, http://www.springframework.org/schema/context/spring-context-4.1.xsd=org/springframework/context/config/spring-context-4.1.xsd, http://www.springframework.org/schema/beans/spring-beans-2.5.xsd=org/springframework/beans/factory/xml/spring-beans-2.5.xsd, http://www.springframework.org/schema/tool/spring-tool-4.2.xsd=org/springframework/beans/factory/xml/spring-tool-4.2.xsd, http://www.springframework.org/schema/jee/spring-jee-4.2.xsd=org/springframework/ejb/config/spring-jee-4.2.xsd, http://www.springframework.org/schema/aop/spring-aop.xsd=org/springframework/aop/config/spring-aop-4.2.xsd}
11:38:15.833 [main] DEBUG o.s.b.f.xml.PluggableSchemaResolver - Found XML schema [http://www.springframework.org/schema/beans/spring-beans.xsd] in classpath: org/springframework/beans/factory/xml/spring-beans-4.2.xsd
11:38:15.862 [main] DEBUG o.s.b.f.x.DefaultBeanDefinitionDocumentReader - Loading bean definitions
11:38:15.871 [main] DEBUG o.s.b.f.xml.XmlBeanDefinitionReader - Loaded 1 bean definitions from location pattern [applicationContext.xml]
11:38:15.872 [main] DEBUG o.s.c.s.ClassPathXmlApplicationContext - Bean factory for org.springframework.context.support.ClassPathXmlApplicationContext@71c7db30: org.springframework.beans.factory.support.DefaultListableBeanFactory@4d95d2a2: defining beans [helloWorld]; root of factory hierarchy
11:38:15.888 [main] DEBUG o.s.c.s.ClassPathXmlApplicationContext - Unable to locate MessageSource with name 'messageSource': using default [org.springframework.context.support.DelegatingMessageSource@11758f2a]
11:38:15.889 [main] DEBUG o.s.c.s.ClassPathXmlApplicationContext - Unable to locate ApplicationEventMulticaster with name 'applicationEventMulticaster': using default [org.springframework.context.event.SimpleApplicationEventMulticaster@4671e53b]
11:38:15.890 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Pre-instantiating singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@4d95d2a2: defining beans [helloWorld]; root of factory hierarchy
11:38:15.890 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating shared instance of singleton bean 'helloWorld'
11:38:15.890 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Creating instance of bean 'helloWorld'
11:38:15.898 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Eagerly caching bean 'helloWorld' to allow for resolving potential circular references
11:38:15.914 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Finished creating instance of bean 'helloWorld'
11:38:15.915 [main] DEBUG o.s.c.s.ClassPathXmlApplicationContext - Unable to locate LifecycleProcessor with name 'lifecycleProcessor': using default [org.springframework.context.support.DefaultLifecycleProcessor@2f8f5f62]
11:38:15.915 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'lifecycleProcessor'
11:38:15.917 [main] DEBUG o.s.c.e.PropertySourcesPropertyResolver - Searching for key 'spring.liveBeansView.mbeanDomain' in [systemProperties]
11:38:15.917 [main] DEBUG o.s.c.e.PropertySourcesPropertyResolver - Found key 'spring.liveBeansView.mbeanDomain' in [systemProperties] with type [String] and value ''
11:38:15.919 [main] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'helloWorld'
Welcome to the Spring world

生命周期信息

ApplicationContextAware:实现setApplicationContext方法。
BeanNameAware:实现setBeanName方法。
InitializingBean:实现InitializingBean方法。
BeanFactoryAware:实现setBeanFactory方法。
BeanPostProcessor:实现postProcessBeforeInitialization和postProcessAfterInitialization方法。
DisposableBean:实现destroy方法。

在HelloWorld类中添加如下方法:

    public void myInit() {
        System.out.println("custom myInit is called ");
    }

    public void myDestroy() {
        System.out.println("custom myDestroy is called ");
    }

修改xml文件:

<bean id="helloWorld" class="com.packt.lifecycle.HelloWorld"
init-method="myInit" destroy-method="myDestroy">
<property name="message" value="Welcome to the Spring world">
</property>
</bean>

修改HelloWorldExample类

   public static void main(String[] args) {
        AbstractApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        HelloWorld world = (HelloWorld) context.getBean("helloWorld");
        context.getBean("helloWorld");
        System.out.println(world.getMessage());
        context.registerShutdownHook();
    }

现在执行可以看到“custom myInit is called ”等信息。

autowiring和注解

Spring容器可以自动处理bean之间的依赖关系,这样就没必要使用 <constructor-arg>和 <constructor-arg>标签,简化了应用程序上下文XML配置。
autowiring的类型如下:
•no:默认没有。
•byName:使用配置文件中相同名字的beans定义。
•byType的:使用配置文件中相同属性的beans定义。如果有多个则抛出异常。
•constructor:类似type,但基于构造类型。
•default:先使用constructor,不成功则基于byType。

修改applicationContext.xml:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    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.xsd

http://www.springframework.org/schema/context


http://www.springframework.org/schema/context/spring-context-4.1.xsd

    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.1.xsd
    http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.1.xsd
    ">
    <context:annotation-config/>
       <bean name="message" id="message" class="java.lang.String">
           <constructor-arg value="auto wired" />
    </bean>

    <bean id="helloWorld" class="com.example.HelloWorld">
    </bean>

</beans>

注解类型如下:
•@Required:该注释适用于bean的setter方法
•@Autowired:bean的setter方法,构造函数和属性
•@Qualifier:和@Autowired一起用于限定bean。
通过<context:annotation-config/>开启autowiring的注解。

修改HelloWorld:

package com.example;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.BeanFactoryAware;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.config.BeanPostProcessor;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
public class HelloWorld implements ApplicationContextAware,BeanNameAware, InitializingBean,
        BeanFactoryAware,BeanPostProcessor,  DisposableBean {

    @Autowired
    private String message;
    public String getMessage() {
        return message;
    }

    @Autowired
    public void setMessage(String message) {
        this.message = message;
    }    

    public void setBeanName(String arg0) {
        System.out.println("setBeanName is called with " + arg0);
    }
    @Override
    public void afterPropertiesSet() throws Exception {
        System.out.println("afterPropertiesSet is called ");
    }
    @Override
    public void setBeanFactory(BeanFactory arg0) throws BeansException {
        System.out.println("setBeanFactory is called ");
    }
    public void myInit() {
        System.out.println("custom myInit is called ");
    }
    public void myDestroy() {
        System.out.println("custom myDestroy is called ");
    }

    @Override
    public void destroy() throws Exception {
        System.out.println("destroy is called ");// TODO Auto-generated method stub
    }
    @Override
    public Object postProcessAfterInitialization(Object arg0, String arg1)
            throws BeansException {
        System.out.println("postProcessAfterInitialization is called with "+arg0+" and "+arg1);
        return null;
    }
    @Override
    public Object postProcessBeforeInitialization(Object arg0, String arg1)
            throws BeansException {
        System.out.println("postProcessBeforeInitialization is called with "+arg0+" and "+arg1);
        return null;
    }
    @Override
    public void setApplicationContext(ApplicationContext arg0)
            throws BeansException {
        System.out.println("setApplicationContext is called ");    
    }
}

现在执行可以看到”auto wired”信息。

aspect

AOP是Spring框架的关键组件之一。面向对象编程不能很好地处理一些通用功能。比如:
•日志记录和跟踪
•事务管理
•安全
•缓存
•错误处理
•性能监控
•自定义业务规则
•事件处理

AOP覆盖OOP的数据驱动层,用AspectJ和Spring AOP的实现:
•AspectJ:这是原来的AOP技术(从第一个版本的日期1995开始),提供了全面的,面向方向的编程语言,使用字节码修改。
•Spring AOP的:基于Java的AOP框架,它使用动态代理,主要用来解决企业级问题。

•Join point连接点:插入逻辑的连接点。通常在:
°方法调用
°类初始化
°对象初始化
•Advice建议:连接点执行的代码。3种如下:
°before。
°after。
°around(兼具before和after的功能。
•Pointcut切入点:连接点的集合,通常是多个实际Join point的执行点。
•Aspect切面:实现横切,连接advice和Pointcut。一个应用可以有
任何数目的方面的,根据不同的要求。
•Weaving编织:应用到代码的过程,有三种类型:
°编译时
°类加载
°运行时

•目标:
•简介:修改该结构,引入额外的方法或字段。

有两种类型的AOP:
•静态AOP
°weaving是构建过程中的另一个步骤
°例如Java程序,可以过改变和修改应用程序的实际字节码
•动态AOP
°weaving在运行时动态地进行
°很容易改变的weaving过程而无需重新编译
Spring AOP是基于代理。关于代理的更多资料: http://en.wikipedia.org/wiki/Proxy_pattern,下面我们做个简单的演示:

创建接口IMessageWriter:

package com.example;
public interface IMessageWriter {
    void writeMessage();
}

MessageWriter类实现IMessageWriter:

package com.example;
public class MessageWriter implements IMessageWriter {

    @Override
    public void writeMessage() {
        System.out.print("World");
    }
}

调用 writeMessage()是连接点。我们想把“World”把改成“ Hello World !”。MethodInterceptor是AOP标准接口。新建类MessageDecorator:

package com.example;
import org.aopalliance.intercept.MethodInterceptor;
import org.aopalliance.intercept.MethodInvocation;
public class MessageDecorator implements MethodInterceptor {
    public Object invoke(MethodInvocation invocation) throws Throwable {
        System.out.print("Hello ");
        Object retVal = invocation.proceed();
        System.out.println("!");
        return retVal;
    }
}

AOPTest类使用ProxyFactory类创建代理:

package com.example;
import org.springframework.aop.framework.ProxyFactory;
public class AOPTest {
    public static void main(String[] args) {
        MessageWriter target = new MessageWriter();
        // create the proxy
        ProxyFactory pf = new ProxyFactory();
        // Add the given AOP Alliance advice to the tail
        // of the advice (interceptor) chain
        pf.addAdvice(new MessageDecorator());
        // Set the given object as target
        pf.setTarget(target);
        // Create a new proxy according to the
        // settings in this factory
        MessageWriter proxy = (MessageWriter) pf.getProxy();
        // write the messages
        target.writeMessage();
        System.out.println("");
        // use the proxy
        proxy.writeMessage();
    }
}

Spring JDBC

Spring Data Access Object (DAO)支持统一的方式访问JDBC, Hibernate或JDO。Spring还可以处理异常,转换为未检查或者运行时。
DAO支持类如下:
•  JdbcDaoSupport
•  HibernateDaoSupport
•  JdoDaoSupport
•  JpaDaoSupport

通常的JDBC访问数据库代码如下:
1.定义连接参数。
2.打开连接。
3.指定的语句。
4.准备和执行该语句。
5.设置循环遍历结果(如果有的话)。
6.处理每个迭代。
7.处理异常。
8.处理事务。
9.关闭连接。

Spring简化为如下:
1.指定语句。
2.处理每个迭代。

Spring-JDBC事务框架包含如下包:
•  org.springframework.jdbc.core
•  org.springframework.jdbc.datasource
•  org.springframework.jdbc.object
•  org.springframework.jdbc.support

org.springframework.jdbc.core包含如下类:
•  JdbcTemplate
•  不同的回调接口
•  其他相关类

org.springframework.jdbc.datasource包有以下类:
•便于数据源访问的工具类
•各种简单的DataSource实现,用于在J2EE容器之外测试和运行未修改的JDBC代码
•utility类提供静态方法从JNDI获得连接和必要时关闭连接。
•支持绑定线程的连接,例如DataSourceTransactionManager

org.springframework.jdbc.object包含以下内容:
•线程安全并可重用的数据库查询,更新和存储过程类
•这种方法是通过JDO模型,查询对象与数据库断开连接
•JDBC的高层抽象依赖于底层抽象org.springframework.jdbc.core。

该org.springframework.jdbc.support包包含以下内容:
•SQLException的转换功能和一些工具类
•转换异常
•使用Spring JDBC抽象层的代码不需要实现JDBC-或者RDBMS特定的错误处理
•所有unchecked异常。

JdbcTemplate类是org.springframework.jdbc.core的主类。它处理了资源创建和释放,简化了JDBC的使用。这有助于避免通用错误,如不关闭连接。它执行核心JDBC工作流,如语句创建和执行。

TestContext框架介绍

Spring的TestContext框架是一个通用的,注解驱动的框架,用于单元测试和集成测试。框架的资源位于org.springframework.test.context包,约定优于配置,每个配置都有默认值,通过注解可以修改非约定的配置。支持JUnit和TestNG,比如可以自定义JUnit执行器来支持非入侵的POJO测试类。

框架包含的类如下:
•TestContext: 该类提供在测试执行的上下文和上下文管理和缓存支持。加载应用程序上下文使用ContextLoader或SmartContextLoader接口。
•TestContextManager:框架的主入口点。它管理单个TestContext类和发布事件到TestExecutionListener实现。

这是测试执行要点:
°在静态类方法之前,
°在测试执行方法之前,
°在测试实例的准备
°测试执行方法之后
°在静态类方法之后

以下是接口:
•TestExecutionListener
•ContextLoader:这个接口加载集成测试的ApplicationContext
•SmartContextLoader:扩展ContextLoader接口,在Spring3.1引入,处理资源位置,注解类,或上下文初始化,还可以设置 active bean profiles ( @ActiveProfiles )和属性资源。

每个测试有一个TestContextManager类,它管理TestContext并处理 dependency injection, dirty checks, transactional support等。TestContextManager委派TestExecutionListener(通过dependency injection,managing transactions实现实际的测试执行)。

默认TestExecutionListener的实现方式注册方式如下:
• ServletTestExecutionListener: WebApplicationContext的Servlet API mock。
• DependencyInjectionTestExecutionListener
• DirtiesContextTestExecutionListener:检查上下文,确实测试执行时是否有脏bean。它还处理@DirtiesContext注解。
• TransactionalTestExecutionListener:这提供了事务性支持
•SqlScriptsTestExecutionListener:通过@sql注解执行SQL脚本

自定义TestExecutionListener

新建Spring maven新工程SpringTests。

新建类SpringTestsApplication:

package com.example;
import org.springframework.context.ApplicationContext;
import org.springframework.test.context.TestContext;
import org.springframework.test.context.TestExecutionListener;

public class SysOutTestExecutionListener implements TestExecutionListener {

    @Override 
    public void afterTestClass(TestContext testContext) throws Exception {
        ApplicationContext ctx = testContext.getApplicationContext();
        System.out.println("In afterTestClass for class = " + testContext.getTestClass());
    }

    @Override 
    public void afterTestMethod(TestContext testContext) throws Exception {
        System.out.println("In afterTestMethod for = " + testContext.getTestMethod().getName());
    }

    @Override public void beforeTestClass(TestContext testContext) throws Exception {
        System.out.println("In beforeTestClass for class = " + testContext.getTestClass());
    }

    @Override public void beforeTestMethod(TestContext testContext) throws Exception {
        System.out.println("In beforeTestMethod for =" + testContext.getTestMethod().getName());
    }
    @Override
    public void prepareTestInstance(TestContext testContext) throws Exception {
        System.out.println("In prepareTestInstance for= " + testContext.getTestInstance());
    }
}

新建类:

package com.example;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.TestExecutionListeners;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations="classpath:applicationContext.xml")
@TestExecutionListeners({SysOutTestExecutionListener.class})
public class TestExecutionListenerTest {

    @Test
    public void someTest() throws Exception {
        System.out.println("executing someTest");
    }

    @Test
    public void someOtherTest() throws Exception {
        System.out.println("executing someOtherTest");
    }
}

新建文件:SpringTests/src/main/resources/applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:aop="http://www.springframework.org/schema/aop"
    xmlns:tx="http://www.springframework.org/schema/tx"
    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.xsd

http://www.springframework.org/schema/context


http://www.springframework.org/schema/context/spring-context-4.1.xsd

    http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.1.xsd
    http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.1.xsd
    ">
</beans>

配置Spring profile

Spring3.1引入了profile。它可以把一个包可以部署在各种环境中,如开dev, test, prod, perf等。
定义的系统属性spring.profiles.active,或使用 @ActiveProfiles注解测试类即可。

修改: applicationContext.xml

<beans xmlns="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-3.1.xsd
       http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

    <bean name="noProfileBean" id="message"
        class="java.lang.String">
        <constructor-arg value="I'm a free bean" />
    </bean>     

    <beans profile="dev">
        <bean name="message" id="message" class="java.lang.String">
            <constructor-arg value="I'm a dev bean" />
        </bean>
    </beans>  

     <beans profile="prod">
        <bean name="message" id="message" class="java.lang.String">
        <constructor-arg value="I'm a prod bean" />
        </bean>
    </beans>

</beans>

新建测试类:

package com.example;

import static org.junit.Assert.*;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.test.context.ActiveProfiles;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations="classpath:applicationContext.xml")
@ActiveProfiles(profiles={"dev"})
public class ProfileTest {

    @Autowired
    ApplicationContext context;

    @Test
    public void profile() throws Exception {
        assertEquals("I'm a dev bean", context.getBean("message"));
        //assertEquals("I'm a free bean", context.getBean("noProfileBean"));
    }
}

除了ActiveProfiles注解,也可以在环境变量中指定。比如spring.profiles.active = dev。

环境mock

后面补充

JNDI查找mock

后面补充

ReflectionTestUtils

org.springframework.test.util包的ReflectionTestUtils类包含不少反射方法,如设置非公开域或调用private/protected的setter方法等。
如下:
•ORM框架,如JPA和Hibernate
•Spring的注解支持,如@Autowired,@Inject,和@Resource,这对于private/protected域的提供依赖注入,setter方法和配置方法。

下面的示例演示ReflectionUtils的功能:
新增方法:Secret

package com.example;

public class Secret {

    private String secret;
    public void initiate(String key) {
        this.secret = key.replaceAll("a", "z").replaceAll("i", "k");
    }
}

测试代码

package com.example;

import static org.junit.Assert.*;
import java.lang.reflect.Field;
import org.junit.Test;
import org.springframework.util.ReflectionUtils;

public class ReflectionUtilsTest {

    @Test
    public void private_field_access() throws Exception {

        Secret myClass = new Secret();
        myClass.initiate("aio");
        Field secretField = ReflectionUtils.findField(Secret.class, "secret", String.class);
        assertNotNull(secretField);
        ReflectionUtils.makeAccessible(secretField);
        assertEquals("zko", ReflectionUtils.getField(secretField, myClass)); 
        ReflectionUtils.setField(secretField, myClass, "cool");
        assertEquals("cool", ReflectionUtils.getField(secretField, myClass));
    }
}
public interface MyInterface {

    // constant definition
    String URL = "http://www.vogella.com";

    // public abstract methods
    void test();
    void write(String s);

    // default method
    default String reserveString(String s){
      return new StringBuilder(s).reverse().toString();
    }
}
public class MyClassImpl implements MyInterface {
    @Override
    public void test() {
    }
    @Override
    public void write(String s) {
    }

    public static void main(String[] args) {
        MyClassImpl impl = new MyClassImpl();
        System.out.println(impl.reserveString("Lars Vogel"));
    }
}
public interface A {
  default void m() {}
}

public interface B {
  default void m() {}
}

public class C implements A, B {
  @Override
  public void m() {}
}
public class C implements A, B {
  @Override
  public void m() {A.super.m();}
}


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