spring 学习2-Spring Configuration in detail

1.Bean Life-Cycle Management

<bean id="simpleBean1" 
class="com.apress.prospring3.ch5.lifecycle.SimpleBean" 
init-method="init" />

<bean id="destructiveBean" 
class="com.apress.prospring3.ch5.lifecycle.DestructiveBean" 
destroy-method="destroy"/>

public class SimpleBeanWithInterface implements InitializingBean{ 
private static final String DEFAULT_NAME = "Luke Skywalker"; 
private String name = null; 
private int age = Integer.MIN_VALUE; 
public void setName(String name) { 
this.name = name; 
} 
public void setAge(int age) { 
this.age = age; 
} 
public void myInit() { 
System.out.println("My Init"); 
} 
public void afterPropertiesSet() throws Exception { 
System.out.println("Initializing bean"); 
if (name == null) { 
System.out.println("Using default name"); 
name = DEFAULT_NAME; 
}

public class DestructiveBeanWithInterface implements InitializingBean, 
DisposableBean{ 
private InputStream is = null; 
public String filePath = null; 
public void afterPropertiesSet() throws Exception { 
System.out.println("Initializing Bean"); 
if (filePath == null) { 
throw new IllegalArgumentException( 
"You must specify the filePath property of " + DestructiveBean.class); 
} 
is = new FileInputStream(filePath); 
} 
public void destroy() { 
System.out.println("Destroying Bean"); 
if (is != null) { 
try {  
is.close(); 
is = null; 
} catch (IOException ex) { 
System.err.println("WARN: An IOException occured" 
+ " trying to close the InputStream"); 
} 
} 
} 
public void setFilePath(String filePath) { 
this.filePath = filePath; 
}

public class SimpleBeanWithJSR250 { 
// Codes omitted 
@PostConstruct 
public void init() throws Exception { 
// Rest of codes omitted 
} 
}

public class DestructiveBeanWithJSR250 { 
private InputStream is = null; 
public String filePath = null; 
@PostConstruct 
public void afterPropertiesSet() throws Exception { 
System.out.println("Initializing Bean"); 
if (filePath == null) { 
throw new IllegalArgumentException( 
"You must specify the filePath property of " + DestructiveBean.class); 
} 
is = new FileInputStream(filePath); 
} 
@PreDestroy 
public void destroy() { 
System.out.println("Destroying Bean"); 
if (is != null) { 
try { 
is.close(); 
is = null; 
} catch (IOException ex) { 
System.err.println("WARN: An IOException occured" 
+ " trying to close the InputStream"); 
} 
} 
} 
public void setFilePath(String filePath) { 
this.filePath = filePath; 
}

2.Making Your Beans “Spring Aware”

public class ShutdownHookBean implements ApplicationContextAware { 
private ApplicationContext ctx; 
public void setApplicationContext(ApplicationContext ctx) 
throws BeansException { 
if (ctx instanceof GenericApplicationContext) { 
((GenericApplicationContext) ctx).registerShutdownHook(); 
} 
} 
}

<bean id="destructiveBean" 
class="com.apress.prospring3.ch5.lifecycle.DestructiveBeanWithInterface"> 
<property name="filePath"> 
<value>d:/temp/test.txt</value> 
</property> 
</bean> 
<bean id="shutdownHook" 
class="com.apress.prospring3.ch5.interaction.ShutdownHookBean"/>

3.Using ApplicationContext and MessageSource

public static void main(String[] args) { 
GenericXmlApplicationContext ctx = new GenericXmlApplicationContext(); 
ctx.load("classpath:appContext/messageSource.xml"); 
ctx.refresh(); 
Locale english = Locale.ENGLISH; 
Locale czech = new Locale("cs", "CZ"); 
System.out.println(ctx.getMessage("msg", null, english)); 
System.out.println(ctx.getMessage("msg", null, czech)); 
System.out.println(ctx.getMessage("nameMsg", new Object[] { "Clarence", 
"Ho" }, english)); 
}

<bean id="messageSource" 
class="org.springframework.context.support.ResourceBundleMessageSource"> 
<property name="basenames"> 
<list> 
<value>buttons</value> 
<value>labels</value> 
</list> 
</property> 
</bean>

4.Using Application Events

public class MessageEvent extends ApplicationEvent { 
private String msg; 
public MessageEvent(Object source, String msg) { 
super(source); 
this.msg = msg; 
} 
public String getMessage() { 
return msg; 
} 
}

public class MessageEventListener implements ApplicationListener<MessageEvent> { 
public void onApplicationEvent(MessageEvent event) { 
MessageEvent msgEvt = (MessageEvent) event; 
System.out.println("Received: " + msgEvt.getMessage()); 
} 
}

public class Publisher implements ApplicationContextAware { 
private ApplicationContext ctx; 
public static void main(String[] args) { 
ApplicationContext ctx = new ClassPathXmlApplicationContext( 
"classpath:events/events.xml"); 
Publisher pub = (Publisher) ctx.getBean("publisher"); 
pub.publish("Hello World!"); 
pub.publish("The quick brown fox jumped over the lazy dog"); 
} 
public void setApplicationContext(ApplicationContext applicationContext) 
throws BeansException { 
this.ctx = applicationContext; 
} 
public void publish(String message) { 
ctx.publishEvent(new MessageEvent(this, message)); 
} 
}

<bean id="publisher" class="com.apress.prospring3.ch5.event.Publisher"/> 
<bean id="messageEventListener" 
class="com.apress.prospring3.ch5.event.MessageEventListener"/>

5.Accessing Resources

public static void main(String[] args) throws Exception{ 
ApplicationContext ctx = new ClassPathXmlApplicationContext( 
"classpath:events/events.xml"); 
Resource res1 = ctx.getResource("file:///d:/temp/test.txt"); 
displayInfo(res1); 
Resource res2 = ctx.getResource("classpath:test.txt"); 
displayInfo(res2); 
Resource res3 = ctx.getResource("http://www.google.co.uk"); 
displayInfo(res3); 
} 
private static void displayInfo(Resource res) throws Exception{ 
System.out.println(res.getClass()); 
System.out.println(res.getURL().getContent()); 
System.out.println(""); 
//getFile(), getInputStream(), or getURL()
}
6. Java Configuration

@Configuration 
public class AppConfig { 
// XML: 
// <bean id="messageProvider" 
class="com.apress.prospring3.ch5.javaconfig.ConfigurableMessageProvider"/> 
@Bean 
public MessageProvider messageProvider() { 
return new ConfigurableMessageProvider(); 
} 
// XML: 
// <bean id="messageRenderer" 
class="com.apress.prospring3.ch5.javaconfig.StandardOutMessageRenderer" 
// p:messageProvider-ref="messageProvider"/> 
@Bean 
public MessageRenderer messageRenderer() { 
MessageRenderer renderer = new StandardOutMessageRenderer(); 
// Setter injection 
renderer.setMessageProvider(messageProvider()); 
return renderer; 
}

@Configuration 
@Import(OtherConfig.class) 
// XML: <import resource="classpath:events/events.xml") 
@ImportResource(value="classpath:events/events.xml") 
// XML: <context:property-placeholder location="classpath:message.properties"/> 
@PropertySource(value="classpath:message.properties") 
// XML: <context:component-scan base-package="com.apress.prospring3.ch5.context"/> 
@ComponentScan(basePackages={"com.apress.prospring3.ch5.context"}) 
@EnableTransactionManagement public class AppConfig { 
@Autowired 
Environment env; 
// XML: 
// <bean id="messageProvider" 
class="com.apress.prospring3.ch5.javaconfig.ConfigurableMessageProvider"/> 
@Bean 
@Lazy(value=true) //XML <bean .... lazy-init="true"/> 
public MessageProvider messageProvider() { 
// Constructor injection 
return new ConfigurableMessageProvider(env.getProperty("message")); 
} 
// XML: 
// <bean id="messageRenderer" 
class="com.apress.prospring3.ch5.javaconfig.StandardOutMessageRenderer" 
// p:messageProvider-ref="messageProvider"/> 
@Bean(name="messageRenderer") 
@Scope(value="prototype") // XML: <bean ... scope="prototype"/> 
@DependsOn(value="messageProvider") // XML: <bean ... depends-on="messageProvider"/> 
public MessageRenderer messageRenderer() { 
MessageRenderer renderer = new StandardOutMessageRenderer(); 
// Setter injection 
renderer.setMessageProvider(messageProvider()); 
return renderer; 
} 
}

7.ConfigurableEnvironment env = ctx.getEnvironment();

MutablePropertySources propertySources = env.getPropertySources();

8.JSR-330

@Named("messageRenderer") 
@Singleton 
public class StandardOutMessageRenderer implements MessageRenderer { 
@Inject 
@Named("messageProvider") 
private MessageProvider messageProvider = null; 
public void render() { 
if (messageProvider == null) { 
throw new RuntimeException( 
"You must set the property messageProvider of class:" 
+ StandardOutMessageRenderer.class.getName()); 
} 
System.out.println(messageProvider.getMessage()); 
} 
public void setMessageProvider(MessageProvider provider) { 
this.messageProvider = provider; 
} 
public MessageProvider getMessageProvider() { 
return this.messageProvider; 
} 
}

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spring 学习2-Spring Configuration in detail

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