Demonstrate Spring 3.2 features

Add "Async" tab and CallableController and DeferredResultController.

Add links for mapping requests by content type via URL extension.

Add global @ExceptionHandler example.

Author: rstoyanchev

src/main/java/org/springframework/samples/mvc/async/CallableController.java

@@ -0,0 +1,83 @@
+package org.springframework.samples.mvc.async;
+
+import java.util.concurrent.Callable;
+
+import org.springframework.stereotype.Controller;
+import org.springframework.ui.Model;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RequestParam;
+import org.springframework.web.bind.annotation.ResponseBody;
+import org.springframework.web.context.request.async.AsyncTask;
+
+@Controller
+@RequestMapping("/async/callable")
+public class CallableController {
+
+
+	@RequestMapping("/response-body")
+	public @ResponseBody Callable<String> callable() {
+
+		return new Callable<String>() {
+			@Override
+			public String call() throws Exception {
+				Thread.sleep(2000);
+				return "Callable result";
+			}
+		};
+	}
+
+	@RequestMapping("/view")
+	public Callable<String> callableWithView(final Model model) {
+
+		return new Callable<String>() {
+			@Override
+			public String call() throws Exception {
+				Thread.sleep(2000);
+				model.addAttribute("foo", "bar");
+				model.addAttribute("fruit", "apple");
+				return "views/html";
+			}
+		};
+	}
+
+	@RequestMapping("/exception")
+	public @ResponseBody Callable<String> callableWithException(
+			final @RequestParam(required=false, defaultValue="true") boolean handled) {
+
+		return new Callable<String>() {
+			@Override
+			public String call() throws Exception {
+				Thread.sleep(2000);
+				if (handled) {
+					// see handleException method further below
+					throw new IllegalStateException("Callable error");
+				}
+				else {
+					throw new IllegalArgumentException("Callable error");
+				}
+			}
+		};
+	}
+
+	@RequestMapping("/custom-timeout")
+	public @ResponseBody AsyncTask<String> callableWithCustomTimeout() {
+
+		Callable<String> callable = new Callable<String>() {
+			@Override
+			public String call() throws Exception {
+				Thread.sleep(2000);
+				return "Callable result";
+			}
+		};
+
+		return new AsyncTask<String>(1000, callable);
+	}
+
+	@ExceptionHandler
+	@ResponseBody
+	public String handleException(IllegalStateException ex) {
+		return "Handled exception: " + ex.getMessage();
+	}
+
+}

src/main/java/org/springframework/samples/mvc/async/DeferredResultController.java

@@ -0,0 +1,77 @@
+package org.springframework.samples.mvc.async;
+
+import java.util.Queue;
+import java.util.concurrent.PriorityBlockingQueue;
+
+import org.springframework.scheduling.annotation.Scheduled;
+import org.springframework.stereotype.Controller;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.ResponseBody;
+import org.springframework.web.context.request.async.DeferredResult;
+import org.springframework.web.servlet.ModelAndView;
+
+@Controller
+@RequestMapping("/async")
+public class DeferredResultController {
+
+	private final Queue<DeferredResult<String>> responseBodyQueue = new PriorityBlockingQueue<DeferredResult<String>>();
+
+	private final Queue<DeferredResult<ModelAndView>> mavQueue = new PriorityBlockingQueue<DeferredResult<ModelAndView>>();
+
+	private final Queue<DeferredResult<String>> exceptionQueue = new PriorityBlockingQueue<DeferredResult<String>>();
+
+
+	@RequestMapping("/deferred-result/response-body")
+	public @ResponseBody DeferredResult<String> deferredResult() {
+		DeferredResult<String> result = new DeferredResult<String>();
+		this.responseBodyQueue.add(result);
+		return result;
+	}
+
+	@RequestMapping("/deferred-result/model-and-view")
+	public @ResponseBody DeferredResult<ModelAndView> deferredResultWithView() {
+		DeferredResult<ModelAndView> result = new DeferredResult<ModelAndView>();
+		this.mavQueue.add(result);
+		return result;
+	}
+
+	@RequestMapping("/deferred-result/exception")
+	public @ResponseBody DeferredResult<String> deferredResultWithException() {
+		DeferredResult<String> result = new DeferredResult<String>();
+		this.exceptionQueue.add(result);
+		return result;
+	}
+
+	@RequestMapping("/deferred-result/timeout-value")
+	public @ResponseBody DeferredResult<String> deferredResultWithTimeoutValue() {
+
+		// Provide a default result in case of timeout and override the timeout value
+		// set in src/main/webapp/WEB-INF/spring/appServlet/servlet-context.xml
+
+		return new DeferredResult<String>(1000L, "Deferred result after timeout");
+	}
+
+	@Scheduled(fixedRate=2000)
+	public void processQueues() {
+		for (DeferredResult<String> result : this.responseBodyQueue) {
+			result.setResult("Deferred result");
+			this.responseBodyQueue.remove(result);
+		}
+		for (DeferredResult<String> result : this.exceptionQueue) {
+			result.setErrorResult(new IllegalStateException("DeferredResult error"));
+			this.exceptionQueue.remove(result);
+		}
+		for (DeferredResult<ModelAndView> result : this.mavQueue) {
+			result.setResult(new ModelAndView("views/html", "javaBean", new JavaBean("bar", "apple")));
+			this.mavQueue.remove(result);
+		}
+	}
+
+	@ExceptionHandler
+	@ResponseBody
+	public String handleException(IllegalStateException ex) {
+		return "Handled exception: " + ex.getMessage();
+	}
+
+}

src/main/java/org/springframework/samples/mvc/async/JavaBean.java

@@ -0,0 +1,30 @@
+package org.springframework.samples.mvc.async;
+
+public class JavaBean {
+
+	private String foo;
+
+	private String fruit;
+
+	public JavaBean(String foo, String fruit) {
+		this.foo = foo;
+		this.fruit = fruit;
+	}
+
+	public String getFoo() {
+		return foo;
+	}
+
+	public void setFoo(String foo) {
+		this.foo = foo;
+	}
+
+	public String getFruit() {
+		return fruit;
+	}
+
+	public void setFruit(String fruit) {
+		this.fruit = fruit;
+	}
+
+}

src/main/java/org/springframework/samples/mvc/convert/ConvertController.java

@@ -12,7 +12,7 @@
 import org.springframework.web.bind.annotation.ResponseBody;
 
 @Controller
-@RequestMapping("/convert/*")
+@RequestMapping("/convert")
 public class ConvertController {
 
 	@RequestMapping("primitive")

src/main/java/org/springframework/samples/mvc/data/RequestDataController.java

@@ -3,6 +3,7 @@
 import org.springframework.http.HttpEntity;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.CookieValue;
+import org.springframework.web.bind.annotation.MatrixVariable;
 import org.springframework.web.bind.annotation.PathVariable;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestHeader;
@@ -12,30 +13,30 @@
 import org.springframework.web.bind.annotation.ResponseBody;
 
 @Controller
-@RequestMapping("/data/*")
+@RequestMapping("/data")
 public class RequestDataController {
 
-	@RequestMapping(value="param")
+	@RequestMapping(value="param", method=RequestMethod.GET)
 	public @ResponseBody String withParam(@RequestParam String foo) {
 		return "Obtained 'foo' query parameter value '" + foo + "'";
 	}
 
-	@RequestMapping(value="group")
+	@RequestMapping(value="group", method=RequestMethod.GET)
 	public @ResponseBody String withParamGroup(JavaBean bean) {
 		return "Obtained parameter group " + bean;
 	}
 
-	@RequestMapping(value="path/{var}")
+	@RequestMapping(value="path/{var}", method=RequestMethod.GET)
 	public @ResponseBody String withPathVariable(@PathVariable String var) {
 		return "Obtained 'var' path variable value '" + var + "'";
 	}
 
-	@RequestMapping(value="header")
+	@RequestMapping(value="header", method=RequestMethod.GET)
 	public @ResponseBody String withHeader(@RequestHeader String Accept) {
 		return "Obtained 'Accept' header '" + Accept + "'";
 	}
 
-	@RequestMapping(value="cookie")
+	@RequestMapping(value="cookie", method=RequestMethod.GET)
 	public @ResponseBody String withCookie(@CookieValue String openid_provider) {
 		return "Obtained 'openid_provider' cookie '" + openid_provider + "'";
 	}

src/main/java/org/springframework/samples/mvc/exceptions/BusinessException.java

@@ -0,0 +1,6 @@
+package org.springframework.samples.mvc.exceptions;
+
+@SuppressWarnings("serial")
+public class BusinessException extends Exception {
+
+}

src/main/java/org/springframework/samples/mvc/exceptions/ExceptionController.java

@@ -8,14 +8,19 @@
 @Controller
 public class ExceptionController {
 
-	@ExceptionHandler
-	public @ResponseBody String handle(IllegalStateException e) {
-		return "IllegalStateException handled!";
-	}
-	
 	@RequestMapping("/exception")
 	public @ResponseBody String exception() {
 		throw new IllegalStateException("Sorry!");
 	}
 
+	@RequestMapping("/global-exception")
+	public @ResponseBody String businessException() throws BusinessException {
+		throw new BusinessException();
+	}
+
+	@ExceptionHandler
+	public @ResponseBody String handle(IllegalStateException e) {
+		return "IllegalStateException handled!";
+	}
+
 }

src/main/java/org/springframework/samples/mvc/exceptions/GlobalExceptionHandler.java

@@ -0,0 +1,15 @@
+package org.springframework.samples.mvc.exceptions;
+
+import org.springframework.web.bind.annotation.ControllerAdvice;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import org.springframework.web.bind.annotation.ResponseBody;
+
+@ControllerAdvice
+public class GlobalExceptionHandler {
+
+	@ExceptionHandler
+	public @ResponseBody String handleBusinessException(BusinessException ex) {
+		return "Handled BusinessException";
+	}
+
+}

src/main/java/org/springframework/samples/mvc/mapping/JavaBean.java

@@ -1,7 +1,10 @@
 package org.springframework.samples.mvc.mapping;
 
+import javax.xml.bind.annotation.XmlRootElement;
+
+@XmlRootElement
 public class JavaBean {
-	
+
 	private String foo = "bar";
 
 	private String fruit = "apple";
@@ -22,4 +25,9 @@ public void setFruit(String fruit) {
 		this.fruit = fruit;
 	}
 
+	@Override
+	public String toString() {
+		return "JavaBean {foo=[" + foo + "], fruit=[" + fruit + "]}";
+	}
+
 }

src/main/java/org/springframework/samples/mvc/mapping/MappingController.java

@@ -2,6 +2,7 @@
 
 import javax.servlet.http.HttpServletRequest;
 
+import org.springframework.http.MediaType;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RequestMapping;
@@ -46,13 +47,18 @@ public class MappingController {
 		return "Mapped by path + method + absence of header!";
 	}
 
-	@RequestMapping(value="/mapping/consumes", method=RequestMethod.POST, consumes="application/json")
+	@RequestMapping(value="/mapping/consumes", method=RequestMethod.POST, consumes=MediaType.APPLICATION_JSON_VALUE)
 	public @ResponseBody String byConsumes(@RequestBody JavaBean javaBean) {
 		return "Mapped by path + method + consumable media type (javaBean '" + javaBean + "')";
 	}
 
-	@RequestMapping(value="/mapping/produces", method=RequestMethod.GET, produces="application/json")
-	public @ResponseBody JavaBean byProduces() {
+	@RequestMapping(value="/mapping/produces", method=RequestMethod.GET, produces=MediaType.APPLICATION_JSON_VALUE)
+	public @ResponseBody JavaBean byProducesJson() {
+		return new JavaBean();
+	}
+
+	@RequestMapping(value="/mapping/produces", method=RequestMethod.GET, produces=MediaType.APPLICATION_XML_VALUE)
+	public @ResponseBody JavaBean byProducesXml() {
 		return new JavaBean();
 	}