<!-- more -->
<action-state id="moreAnswersNeeded">
	<evaluate expression="interview.moreAnswersNeeded()" />
	<transition on="yes" to="answerQuestions" />
	<transition on="no" to="finish" />
</action-state>

方法返回值类型			映射出来的EventId
java.lang.String		直接以字符串的值作为id
java.lang.Boolean		yes (for true), no (for false)
java.lang.Enum			the Enum name
any other type	    	success

<evaluate expression="pojoAction.method(flowRequestContext)" />

public class PojoAction {
	public String method(RequestContext context) {
		...
	}
}

<evaluate expression="customAction" />

public class CustomAction implements Action {
	public Event execute(RequestContext context) {
		...
	}
}

<evaluate expression="multiAction.actionMethod1" />

public class CustomMultiAction extends MultiAction {
	public Event actionMethod1(RequestContext context) {
		...
	}

	public Event actionMethod2(RequestContext context) {
		...
	}
	...
}

public class BookingAction extends MultiAction {
	public Event makeBooking(RequestContext context) {
		   try {
			   Booking booking = (Booking) context.getFlowScope().get("booking");
			   BookingConfirmation confirmation = bookingService.make(booking);
			   context.getFlowScope().put("confirmation", confirmation);
			   return success();
		   } catch (RoomNotAvailableException e) {
			   context.getMessageContext().addMessage(new MessageBuilder().error().
				   .defaultText("No room is available at this hotel").build());
			   return error();
		   }
	}
}

<decision-state id="moreAnswersNeeded">
	<if test="interview.moreAnswersNeeded()" then="answerQuestions" else="finish" />
</decision-state>

<action-state id="doTwoThings">
	<evaluate expression="service.thingOne()">
		<attribute name="name" value="thingOne" />
	</evaluate>
	<evaluate expression="service.thingTwo()">
		<attribute name="name" value="thingTwo" />
	</evaluate>
	<transition on="thingTwo.success" to="showResults" />
</action-state>

public class PrintBoardingPassAction extends AbstractAction {

    @Override
    protected Event doExecute(RequestContext context) throws Exception {
        HttpServletResponse response = (HttpServletResponse)context.getExternalContext().getNativeResponse();
        OutputStream os = response.getOutputStream();
        // 在这里操作os，写入流数据
        os.close();
        context.getExternalContext().recordResponseComplete();
        return success();
    }

}

<dependency>
<!-- more -->
    <groupId>org.springframework.webflow</groupId>
    <artifactId>spring-webflow</artifactId>
    <version>2.4.5.RELEASE</version>
</dependency>

<webflow:flow-location path="/WEB-INF/flows/booking/booking.xml" id="bookHotel" />

<webflow:flow-location-pattern value="/WEB-INF/flows/**/*-flow.xml" />

<!-- my-system-config.xml -->
<webflow:flow-registry id="flowRegistry" parent="sharedFlowRegistry">
    <webflow:flow-location path="/WEB-INF/flows/booking/booking.xml" />
</webflow:flow-registry>

<!-- shared-config.xml -->
<webflow:flow-registry id="sharedFlowRegistry">
    <!-- Global flows shared by several applications -->
</webflow:flow-registry>

<webflow:flow-registry id="flowRegistry" flow-builder-services="flowBuilderServices">
    <webflow:flow-location path="/WEB-INF/flows/booking/booking.xml" />
</webflow:flow-registry>

<webflow:flow-builder-services id="flowBuilderServices"
    conversion-service="conversionService"
    expression-parser="expressionParser"
    view-factory-creator="viewFactoryCreator" />

<bean id="conversionService" class="..." />
<bean id="expressionParser" class="..." />
<bean id="viewFactoryCreator" class="..." />

<webflow:flow-registry id="flowRegistry" flow-builder-services="flowBuilderServices">
	<webflow:location path="/WEB-INF/hotels/booking/booking.xml" />
</webflow:flow-registry>

<!-- 尤其注意这里的development，设置为true时表示开启开发模式，该模式下会在flow定义改变时自动re-load，甚至flow中引用的resource bundle发生了变化都会热重载 -->
<webflow:flow-builder-services id="flowBuilderServices" view-factory-creator="mvcViewFactoryCreator" development="true"/>

<bean id="mvcViewFactoryCreator" class="org.springframework.webflow.mvc.builder.MvcViewFactoryCreator">
	<!-- myExistingViewResolverToUseForFlows就是我们常用的视图解析器，注意这里引用的是一个列表 -->
	<property name="viewResolvers" ref="myExistingViewResolverToUseForFlows"/>
</bean>

... ... 
... ...
<!-- 做验证时使用的是javaconfig的形式，这种形式并没有验证过 -->
<property name="myExistingViewResolverToUseForFlows">
    <list>
        <ref bean="viewResolver" />
    </list>
</property>

<bean id="viewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
   <property name="prefix" value="/WEB-INF/"/>
   <property name="suffix" value=".jsp"/>
</bean>

<webflow:flow-builder-services expression-parser="expressionParser"/>

<bean id="expressionParser" class="org.springframework.webflow.expression.el.WebFlowELExpressionParser">
    <constructor-arg>
        <bean class="org.jboss.el.ExpressionFactoryImpl" />
    </constructor-arg>
</bean>

<webflow:flow-registry id="flowRegistry" flow-builder-services="flowBuilderServices" ... />

<webflow:flow-builder-services id="flowBuilderServices" conversion-service="defaultConversionService" ... />

<bean id="defaultConversionService" class="org.springframework.binding.convert.service.DefaultConversionService">
	<constructor-arg ref="applicationConversionSevice"/>
</bean>

<bean id="applicationConversionService" class="somepackage.ApplicationConversionServiceFactoryBean">

public class ApplicationConversionServiceFactoryBean extends FormattingConversionServiceFactoryBean {
    @Override
    protected void installFormatters(FormatterRegistry registry) {
        // ...
    }
}

<!-- 这里是为特定的flow应用该监听器，当不设criteria属性时，将对所有flow应用 -->
<webflow:flow-execution-listeners>
    <webflow:listener ref="securityListener" criteria="securedFlow1,securedFlow2"/>
</webflow:flow-execution-listeners>

<servlet>
	<servlet-name>Spring MVC Dispatcher Servlet</servlet-name>
	<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
	<init-param>
		<param-name>contextConfigLocation</param-name>
		<param-value>/WEB-INF/web-application-config.xml</param-value>
	</init-param>
</servlet>

<servlet-mapping>
	<servlet-name>Spring MVC Dispatcher Servlet</servlet-name>
	<!-- 不能使用类型/*的通配符进行匹配，否则会出现jsp不解析直接回发给浏览器的情况 -->
	<url-pattern>/</url-pattern>
</servlet-mapping>

<!-- Enables FlowHandler URL mapping -->
<bean class="org.springframework.webflow.mvc.servlet.FlowHandlerAdapter">
	<!-- flowExecutor就是前文声明的执行器 -->
	<property name="flowExecutor" ref="flowExecutor" />
</bean>

<!-- Maps request paths to flows in the flowRegistry;
	e.g. a path of /hotels/booking looks for a flow with id "hotels/booking" -->
<bean class="org.springframework.webflow.mvc.servlet.FlowHandlerMapping">
	<!-- flowRegistry就是前文声明的注册器 -->
	<property name="flowRegistry" ref="flowRegistry"/>
	<property name="order" value="0"/>
</bean>

public interface FlowHandler {

	public String getFlowId();

	public MutableAttributeMap createExecutionInputMap(HttpServletRequest request);

	public String handleExecutionOutcome(FlowExecutionOutcome outcome,
		HttpServletRequest request, HttpServletResponse response);

	public String handleException(FlowException e,
		HttpServletRequest request, HttpServletResponse response);
}

<!-- 这里的BookingHandler只是一个例子，实际用时替换成我们自己的Handler -->
<bean name="hotels/booking" class="org.springframework.webflow.samples.booking.BookingFlowHandler" />

public class BookingFlowHandler extends AbstractFlowHandler {
	// handlExecutionOutcome()方法返回的String代表的是重定向的地址
	public String handleExecutionOutcome(FlowExecutionOutcome outcome,
										HttpServletRequest request, HttpServletResponse response) {
		if (outcome.getId().equals("bookingConfirmed")) {
			return "/booking/show";
		} else {
			return "/hotels/index";
		}
	}
}
// 当flow id为bookinConfirmed时，重定向到/booking/show，否则重定向到/hotels/index

<end-state view="externalRedirect:http://springframework.org"/>
<!-- 在流程结束时，跳转到spring首页 -->

public class WebInitializer extends AbstractAnnotationConfigDispatcherServletInitializer {

	@Override
	protected Class<?>[] getRootConfigClasses() {
		return null;
	}

	@Override
	protected Class<?>[] getServletConfigClasses() {
		return new Class<?>[] {MainConfig.class, RegisterConfig.class};
	}

	@Override
	protected String[] getServletMappings() {
		return new String[] {"/"};
	}

}

@Configuration
@EnableWebMvc
@ComponentScan("cn.floyd.pw")
public class MainConfig extends WebMvcConfigurerAdapter{

	@Bean(name="viewResolver")
	public ViewResolver getViewResolver() {
		InternalResourceViewResolver resolver = new InternalResourceViewResolver();
		resolver.setPrefix("/WEB-INF/jsp/");
		resolver.setSuffix(".jsp");
		return resolver;
	}
	
	@Bean
	public MultipartResolver multipartResolver() throws IOException {
	    CommonsMultipartResolver resolver = new CommonsMultipartResolver();
	    return resolver;
	}

	// enable the static resource
	@Override
	public void configureDefaultServletHandling(DefaultServletHandlerConfigurer configurer) {
		configurer.enable();
	}
	
	@Bean
    public FlowHandlerAdapter flowHandlerAdapter(@Autowired FlowExecutor flowExecutor) {
	    System.out.println("init flowHandlerAdapter");
        FlowHandlerAdapter adapter = new FlowHandlerAdapter();
        adapter.setFlowExecutor(flowExecutor);
        
        return adapter;
    }
    
    @Bean
    public FlowHandlerMapping flowHandlerMapping(@Autowired FlowDefinitionRegistry flowRegistry) {
        System.out.println("init flowHandlerMapping");
        FlowHandlerMapping mapping = new FlowHandlerMapping();
        mapping.setOrder(0);
        mapping.setFlowRegistry(flowRegistry);
        
        return mapping;
    }
	
}

@Configuration
public class RegisterConfig extends AbstractFlowConfiguration {

    // 用于注册flow
    @Bean("flowRegistry")
    public FlowDefinitionRegistry flowRegistry(@Autowired FlowBuilderServices flowBuilderServices) {
        
        return getFlowDefinitionRegistryBuilder()
                .setBasePath("/WEB-INF/jsp/flow")
                .addFlowLocation("/config/search-flow.xml")
                .setFlowBuilderServices(flowBuilderServices)
                .build();
    }
    
    @Bean
    public FlowBuilderServices flowBuilderServices(@Autowired MvcViewFactoryCreator mvcViewFactoryCreator) {
        return getFlowBuilderServicesBuilder()
                .setViewFactoryCreator(mvcViewFactoryCreator)
                .build();
    }
    
    @Bean
    public MvcViewFactoryCreator mvcViewFactoryCreator(@Autowired ViewResolver viewResolver) {
        MvcViewFactoryCreator creator = new MvcViewFactoryCreator();
        List<ViewResolver> list = new ArrayList<ViewResolver>();
        list.add(viewResolver);
        creator.setViewResolvers(list);
        
        return creator;
    }
    
    @Bean
    public FlowExecutor flowExecutor(@Autowired FlowDefinitionRegistry flowRegistry) {
        return getFlowExecutorBuilder(flowRegistry).build();
    }
    
}