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AdvancedMappingController.java

package lishy.controllers.web;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping("/advanced.html")
public class AdvancedMappingController {
    
    @RequestMapping(params="param-one")
    public ModelAndView paramPresent() {    
        return new ModelAndView("advanced", "message", "Request parameter is present"); 
    }
    
    @RequestMapping(params={"param-one", "!param-two"})
    public ModelAndView paramAbsent() {    
        return new ModelAndView("advanced", "message", "Request parameter is absent"); 
    }

    @RequestMapping(params={"type=1", "param=abc"} )
    public ModelAndView paramEqualsValue() {
        return new ModelAndView("advanced", "message", "Request parameter is equal to a value");
    }
    
    @RequestMapping(method=RequestMethod.GET)
    public ModelAndView getRequest() {
        return new ModelAndView("advanced", "message", "A GET request "); 
    }
    
    @RequestMapping(method=RequestMethod.POST)
    public ModelAndView postRequest() {
        return new ModelAndView("advanced", "message", "A POST request"); 
    }

    @RequestMapping(headers="content-type=text/*")
    public ModelAndView headers() {
        return new ModelAndView("advanced", "message", "Narrowing with request headers"); 
    }
    
}

ArgumentsController.java

package lishy.controllers.web;

import java.util.Locale;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.CookieValue;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping("/argument/*")
public class ArgumentsController {
    
    @RequestMapping
    public ModelAndView cookieValue(@CookieValue("JSESSIONID") String cookieValue) {
        return new ModelAndView("arguments", 
                                "message", 
                                "Session id is " + cookieValue);        
    }
    
    @RequestMapping
    public ModelAndView cookie(@CookieValue("JSESSIONID") Cookie cookie) {        
        return new ModelAndView("arguments", 
                                "message", 
                                "Cookie name " + cookie.getName() +
                                ", value " + cookie.getValue());        
    }
    
    @RequestMapping
    public ModelAndView otherArguments(HttpServletRequest request,
                                       HttpSession session,
                                       Locale locale) {        
        return new ModelAndView("arguments", 
                                "message", 
                                "Host: " + request.getLocalName() +
                                ", session id: " + session.getId() +
                                ", locale: " + locale.getDisplayName());
    }
    
}

MethodReturnTypeController.java

package lishy.controllers.web;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.HashMap;
import java.util.Map;

import lishy.controllers.DomainObject;

import org.springframework.stereotype.Controller;
import org.springframework.ui.ExtendedModelMap;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
public class MethodReturnTypeController {
    
    @RequestMapping(value="/model-and-view.html")
    public ModelAndView modelAndView() {          
        ModelAndView modelAndView = new ModelAndView("return-types");
        modelAndView.addObject("message", "This is added to the model");
        modelAndView.addObject("anotherMessage", " and so is this");
        return modelAndView;                      
    }
    
    @RequestMapping(value="/view-name.html")
    public String viewNameOnly(Model model) {   
        model.addAttribute("message", "A return type of String is a view name");
        return "return-types";                
    }
    
    @RequestMapping(value="/return-types.html", params="model")
    public Model model() {   
        return new ExtendedModelMap()
            .addAttribute("message", "This is added to a Model object")
            .addAttribute(new DomainObject(200, "an object with a default attribute name"));
    }
    
    @RequestMapping(value="/return-types.html", params="map")
    public Map<String, String> map() {   
        Map<String, String> modelData = new HashMap<String, String>();
        modelData.put("message", "This is added to a Map object"); 
        modelData.put("anotherMessage", " and so is this");  
        return modelData;
    }
    
    @RequestMapping(value="/return-types.html", params="void")
    public void voidReturnType(PrintWriter writer) throws IOException {   
        writer.print("<html><body>" +
                     "<h1>Raw Servlet Response</h1>" +
                     "<a href='model-and-view.html'>back</a>" +
                     "</body></html>");
    }
     
}

ModelAttributeController.java

package lishy.controllers.web;

import java.util.ArrayList;
import java.util.List;

import lishy.controllers.DomainObject;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;

@Controller
public class ModelAttributeController {
    
    @RequestMapping(value="/model-attributes.html", params="primitive")
    @ModelAttribute("number") public int primitiveAttribute() {
        return 1234567890;              
    }   
    
    @RequestMapping(value="/model-attributes.html", params="object")
    @ModelAttribute("myData") public DomainObject namedAttribute() {
        return new DomainObject(100, "an object with a named model attribute");
    }
    
    @RequestMapping(value="/model-attributes.html", params="default-name")
    @ModelAttribute public DomainObject defaultAttributeName() {
        return new DomainObject(200, "an object with a default attribute name");
    }
    
    @RequestMapping(value="/model-attributes.html", params="collection")
    @ModelAttribute public List<DomainObject> collection() {
        List<DomainObject> objects = new ArrayList<DomainObject>();
        for (int i=1; i<=3; i++) {
            objects.add(new DomainObject(i, "object with id " + i));
        }   
        return objects;             
    }
    
    @ModelAttribute("ref") public String refData() {
        return "Reference data is added to the model for each request";
    }
    
    @RequestMapping(value="/model-attributes.html", params="ref")
    @ModelAttribute("msg") public String refParam(@ModelAttribute("ref") String ref) {
        return ref += " and can be accessed by @ModelAttribute annotated parameters";
    } 
    
}

RequestMappingController.java

package lishy.controllers.web;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping("my-path/*")
public class RequestMappingController {
    
    @RequestMapping("one.html")
    public ModelAndView first() {        
        return new ModelAndView("request", "methodName", "First method");
    }
    
    @RequestMapping("tw*.html")
    public ModelAndView second() {        
        return new ModelAndView("request", "methodName", "Second method");
    }

    @RequestMapping
    public ModelAndView third() {          
        return new ModelAndView("request", "methodName", "Third method");
    }
    
    @RequestMapping
    public ModelAndView fourth() {        
        return new ModelAndView("request", "methodName", "Fourth method");
    }

}

RequestParameterController.java

package lishy.controllers.web;

import java.util.Map;

import org.springframework.stereotype.Controller;
import org.springframework.util.MultiValueMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.ModelAndView;

@Controller
@RequestMapping("/param/*")
public class RequestParameterController {
    
    @RequestMapping
    public ModelAndView requestParam(@RequestParam("one") long arg1,
                                     @RequestParam(value="two", required=false) String arg2,
                                     @RequestParam(value="three", defaultValue="-1") int arg3) {
        return new ModelAndView("params", 
                                "message", 
                                "Parameter values are " + arg1 + ", " +  arg2 + " and " + arg3);
    }
    
    @RequestMapping
    public ModelAndView map(@RequestParam Map<String, String> params) {            
        return new ModelAndView("params", 
                                "message", 
                                "Map contains values " + params.values());        
    }
    
    @RequestMapping
    public ModelAndView multiValueMap(@RequestParam MultiValueMap<String, String> params) {
        return new ModelAndView("params", 
                                "message", 
                                "MultiValueMap contains values " + params.values());
    }
    
}

SimpleController.java

package lishy.controllers.web;

import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

@Controller
public class SimpleController {
    
    @RequestMapping(value="/simple.html")
    public ModelAndView simpleRequest() {
        return new ModelAndView("simple", 
                                "text", 
                                "This is added to the model as the 'text' attribute");
    }

}

DomainObject.java

package lishy.controllers;

public class DomainObject {

    private int id;
    private String name;

    public DomainObject() {
        this(987, "this is a typical domain object");
    }
    public DomainObject(int id, String name) {
        this.setId(id);
        this.setName(name);
    }
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }

}

advanced.jsp

<html>
  <body>

    <h1>Advanced Mapping</h1>
   
    <p style="color:green">${message}</p>

    <p>
      <a href="advanced.html?param-one=123¶m-two=abc">Parameter present</a><br/>
      <a href="advanced.html?param-one">Parameter absent</a><br/>
      <a href="advanced.html?type=1¶m=abc">Parameter equals value</a><br/>
    </p>
    
    <p>
      <a href="advanced.html">GET request</a><br/>
    </p>
    
    <form action="advanced.html" method="POST">
      <button type="submit">Post request</button>
    </form>

    <p>
      <a href="../index.html">back</a>
    </p>

  </body>
</html>

arguments.jsp

<html>
  <body>

    <h1>Handler Method Arguments</h1>
   
    <p style="color:green">${message}</p>
      
    <p>  
      <a href="cookieValue.html">Cookie value</a><br/>      
      <a href="cookie.html">Cookie details</a><br/>    
    </p>
    <p>      
      <a href="otherArguments.html">Other arguments</a><br/>
    </p>

    <p>
      <a href="../../index.html">back</a>
    </p>

  </body>
</html>

model-attributes.jsp

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>  

<html>
  <body>
  
    <h1>Model Attributes</h1>
    <span style="color:green">${ref}</span> 
    
    <p>
      <a href="model-attributes.html?primitive">Primitive attribute</a> 
      <span style="color:green">${number}</span>
    </p> 
    
    <p>
      <a href="model-attributes.html?object">Object attribute</a> 
      <span style="color:green">${myData.id} ${myData.name}</span>
    </p> 
    
    <p>
      <a href="model-attributes.html?default-name">Default model attribute name</a>
      <span style="color:green">${domainObject.id} ${domainObject.name}</span>
    </p>
    
    <p>
      <a href="model-attributes.html?collection">Collection</a><br/>
      <c:forEach items="${domainObjectList}" var="domainObject">
        <span style="color:green">${domainObject.id} ${domainObject.name}</span><br/>
      </c:forEach>
    </p>
    
    <p>
      <a href="model-attributes.html?ref">Reference data</a> 
      <span style="color:green">${msg}</span>
    </p>
    
    <p>
      <a href="../index.html">back</a>
    </p>
    
  </body>
</html>

params.jsp

<html>
  <body>

    <h1>Request Parameters</h1>
   
    <p style="color:green">${message}</p>
    
    <p>
      <a href="requestParam.html?one=12345">One parameter</a><br/>
      <a href="requestParam.html?one=12345&two=abc">Two parameters</a><br/>
      <a href="requestParam.html?one=12345&two=abc&three=999">Three parameters</a><br/>
    </p>

    <p>
      <a href="map.html?param1=56789¶m2=xyz¶m3=999">Map</a><br/>
      <a href="multiValueMap.html?p1=111&p1=222&p2=aaa&p2=bbb">MultiValueMap</a><br/>
    </p>

    <p>
      <a href="../../index.html">back</a>
    </p>

  </body>
</html>

request.jsp

<html>
  <body>

    <h1>Request Mapping</h1>
    
    <p style="color:green">${methodName}</p>

    <p>
      <a href="one.html">one</a><br/>
      <a href="two.html">two</a><br/>
      <a href="twenty.html">twenty</a><br/>
      <a href="third.html">third</a><br/>
      <a href="fourth.html">fourth</a><br/>
      <a href="fifth.html">fifth</a> (fails with resource not available)<br/>
    </p>
    
    <p>
      <a href="../../index.html">back</a>
    </p>
    
  </body>
</html>

return-types.jsp

<html>
  <body>
  
    <h1>Handler Method Return Types</h1>
    
    <p style="color:green">${message} ${anotherMessage}</p>
    
    <p>
      <a href="model-and-view.html">Model and View</a> 
      <span style="color:green">${myData.id} ${myData.name}</span>
    </p> 
    
    <p>
      <a href="view-name.html">View name</a>
    </p>
    
    <p>
      <a href="return-types.html?model">Model object</a>
      <span style="color:green">${domainObject.id} ${domainObject.name}</span>
    </p>
    
    <p>
      <a href="return-types.html?map">Map object</a><br/>
    </p>
    
    <p>
      <a href="return-types.html?void">void</a>      
    </p>
    
    <p>
      <a href="../index.html">back</a>
    </p>
    
  </body>
</html>

simple.jsp

<html>
  <body>

    <h1>Simple</h1>
   
    <p style="color:green">${text}</p>

    <p>
      <a href="../index.html">back</a>
    </p>

  </body>
</html>

controllers-servlet.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"
       xmlns:p="http://www.springframework.org/schema/p"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="
           http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
           http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd">

  <context:component-scan base-package="lishy.controllers.web"/>

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

</beans>

web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
         id="WebApp_ID"
         version="2.5">
         
  <display-name>Controllers</display-name>
  
  <servlet>
    <servlet-name>controllers</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <load-on-startup>1</load-on-startup>
  </servlet>

  <servlet-mapping>
    <servlet-name>controllers</servlet-name>
    <url-pattern>/app/*</url-pattern>
  </servlet-mapping>
  
  <welcome-file-list>
    <welcome-file>index.html</welcome-file>
  </welcome-file-list>
  
</web-app>

index.html

<html>
  <body>
  
    <h1>Controllers</h1>
    
    <p>
      <a href="app/simple.html">Simple Controller</a>
    </p>

    <p>
      <a href="app/my-path/one.html">Request Mapping</a>
    </p>

    <p>
      <a href="app/advanced.html">Advanced Mapping</a>
    </p>
    
    <p>
      <a href="app/param/requestParam?one=999">Request Parameters</a>
    </p>
    
    <p>
      <a href="app/argument/cookie">Handler Method Arguments</a>
    </p>
    
    <p>
      <a href="app/model-and-view.html">Handler Method Return Types</a>
    </p>  
        
    <p>
      <a href="app/model-attributes.html?primitive">Model Attributes</a>
    </p>      
    
  </body>
</html>

Guide

Code Reference

Code Highlighter

Controller Fundamentals

Request Mapping

Advanced Mapping

Request Parameters

Handler Method Arguments

Handler Method Return Types

Model Attributes