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Part III: Creating Controllers and JSPs - A HowTo for creating Spring Controllers and JSPs in an AppFuse project.
- This tutorial depends on Part II: Creating new Managers.
About this Tutorial
This tutorial will show you how to create Spring Controllers and JSPs. It'll also demonstrate writing JUnit Tests to test your Controllers. The Controller we create will talk to the PersonManager we created in the Creating Managers tutorial.
- I will tell you how I do stuff in the Real World in text like this.
Let's get started by creating a new Controller and JSP in AppFuse's architecture. If you haven't installed the Spring MVC module at this point, do so by running ant install-springmvc.
Table of Contents
- Create skeleton JSPs using XDoclet
- Create PersonFormControllerTest to test PersonFormController
- Create PersonFormController
- Run PersonFormControllerTest
- Clean up the JSP to make it presentable
- Create Canoo WebTests to test browser-like actions
Create a skeleton JSP using XDoclet
In this step, you'll generate a JSP page to display information from the Person object. It will contain Spring's JSP tags that render table rows for each property in Person.java. The AppGen tool that's used to do this is based off a StrutsGen tool - which was originally written by Erik Hatcher. It's basically just a couple of classes and a bunch of XDoclet templates. All these files are located in extras/appgen.
Here are the simple steps to generating the JSP and a properties file containing the labels for the form elements:
- From the command-line, navigate to "extras/appgen"
- Execute ant -Dobject.name=Person -Dappgen.type=pojo to generate a bunch of files in extras/appgen/build/gen. In fact, it'll generate all the files you need to complete this tutorial. However, let's just grab the ones you need.
- web/WEB-INF/classes/Person.properties (labels for your form elements)
- web/pages/personForm.jsp (JSP file for viewing a single Person)
- web/pages/personList.jsp (JSP file for viewing a list of People)
- Copy the contents of Person.properties into web/WEB-INF/classes/ApplicationResources.properties. These are all the keys you will need for titles/headings and form properties. Here is an example of what you should add to ApplicationResources.properties:
# -- person form --
person.id=Id
person.firstName=First Name
person.lastName=Last Name
person.added=Person has been added successfully.
person.updated=Person has been updated successfully.
person.deleted=Person has been deleted successfully.
# -- person list page --
personList.title=Person List
personList.heading=Persons
# -- person detail page --
personDetail.title=Person Detail
personDetail.heading=Person Information
- Copy personForm.jsp to web/pages/personForm.jsp. Copy personList.jsp to web/pages/personList.jsp.
- The files in the "pages" directory will end up in "WEB-INF/pages" at deployment time. The container provides security for all files below WEB-INF. This applies to client requests, but not to forwards from the DispatchServlet. Placing all JSPs below WEB-INF ensures they are only accessed through Controllers, and not directly by the client or each other. This allows security to be moved up into the Controller, where it can be handled more efficiently, and out of the base presentation layer.
The web application security for AppFuse specifies that all *.html url-patterns should be protected (except for /signup.html and /passwordHint.html). This guarantees that clients must go through an Action to get to a JSP (or at least the ones in pages).
NOTE: If you want to customize the CSS for a particular page, you can add <body id="pageName"/> to the top of the file. This will be slurped up by SiteMesh and put into the final page. You can then customize your CSS on a page-by-page basis using something like the following:
body#pageName element.class { background-color: blue }
- Add keys in ApplicationResources.properties the titles and headings in the JSPs
In the generated JSPs, there are two keys for the title (top of the browser window) and the header (heading in the page). We now need to add these two keys (personDetail.title and personDetail.heading) to ApplicationResources.properties.
# -- person detail page --
personDetail.title=Person Detail
personDetail.heading=Person Information
- Just above, we added "personForm.*" keys to this file, so why do I use personForm and personDetail? The best reason is because it gives a nice separation between form labels and text on the page. Another reason is because all the *Form.* give you a nice representation of all the fields in your database.
I recently had a client who wanted all fields in the database searchable. This was fairly easy to do. I just looked up all the keys in ApplicationResources.properties which contained "Form." and then put them into a drop-down. On the UI, the user was able to enter a search term and select the column they wanted to search. I was glad I followed this Form vs. Detail distinction on that project!
To create a JUnit Test for the PersonFormController, start by creating a PersonFormControllerTest.java file in the test/web/**/action directory.
package org.appfuse.webapp.action;
import org.appfuse.model.Person;
import org.springframework.mock.web.MockHttpServletRequest;
import org.springframework.mock.web.MockHttpServletResponse;
import org.springframework.validation.BindException;
import org.springframework.validation.Errors;
import org.springframework.web.servlet.ModelAndView;
public class PersonFormControllerTest extends BaseControllerTestCase {
private PersonFormController c;
private MockHttpServletRequest request;
private ModelAndView mv;
protected void setUp() throws Exception {
// needed to initialize a user
super.setUp();
c = (PersonFormController) ctx.getBean("personFormController");
}
protected void tearDown() {
c = null;
}
public void testEdit() throws Exception {
log.debug("testing edit...");
request = newGet("/editPerson.html");
request.addParameter("username", "tomcat");
mv = c.handleRequest(request, new MockHttpServletResponse());
assertEquals("personForm", mv.getViewName());
}
public void testSave() throws Exception {
request = newGet("/editPerson.html");
request.addParameter("id", "1");
mv = c.handleRequest(request, new MockHttpServletResponse());
Person person = (Person) mv.getModel().get(c.getCommandName());
assertNotNull(person);
request = newPost("/editPerson.html");
super.objectToRequestParameters(person, request);
request.addParameter("lastName", "Updated Last Name");
mv = c.handleRequest(request, new MockHttpServletResponse());
Errors errors =
(Errors) mv.getModel().get(BindException.ERROR_KEY_PREFIX + "person");
assertNull(errors);
assertNotNull(request.getSession().getAttribute("messages"));
}
public void testRemove() throws Exception {
request = newPost("/editPerson.html");
request.addParameter("delete", "");
request.addParameter("id", "2");
mv = c.handleRequest(request, new MockHttpServletResponse());
assertNotNull(request.getSession().getAttribute("messages"));
}
}
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Nothing will compile at this point (ant compile) because you need to create the PersonFormController that you're referring to in this test.
In src/web/**/action, create a PersonFormController.java file with the following contents:
package org.appfuse.webapp.action;
import java.util.Locale;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.lang.StringUtils;
import org.appfuse.model.Person;
import org.appfuse.service.PersonManager;
import org.springframework.validation.BindException;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.view.RedirectView;
public class PersonFormController extends BaseFormController {
private PersonManager mgr = null;
public void setPersonManager(PersonManager mgr) {
this.mgr = mgr;
}
protected Object formBackingObject(HttpServletRequest request)
throws Exception {
String id = request.getParameter("id");
Person person = null;
if (!StringUtils.isEmpty(id)) {
person = mgr.getPerson(id);
} else {
person = new Person();
}
return person;
}
public ModelAndView processFormSubmission(HttpServletRequest request,
HttpServletResponse response,
Object command,
BindException errors)
throws Exception {
if (request.getParameter("cancel") != null) {
return new ModelAndView(new RedirectView(getSuccessView()));
}
return super.processFormSubmission(request, response, command, errors);
}
public ModelAndView onSubmit(HttpServletRequest request,
HttpServletResponse response, Object command,
BindException errors)
throws Exception {
if (log.isDebugEnabled()) {
log.debug("entering 'onSubmit' method...");
}
Person person = (Person) command;
boolean isNew = (person.getId() == null);
String success = getSuccessView();
Locale locale = request.getLocale();
if (request.getParameter("delete") != null) {
mgr.removePerson(person.getId().toString());
saveMessage(request, getText("person.deleted", locale));
} else {
mgr.savePerson(person);
String key = (isNew) ? "person.added" : "person.updated";
saveMessage(request, getText(key, locale));
if (!isNew) {
success = "editPerson.html?id=" + person.getId();
}
}
return new ModelAndView(new RedirectView(success));
}
}
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In the class above, there are a few methods you might not be familiar with. The formBackingObject() method is used to supply the object this Controller operates on. The processFormSubmission() method is used to detect the cancel button, and onSubmit() is called on POST requests and handles delete/add/update of a user.
There are a few keys you (might) need to add to ApplicationResources.properties to display the success messages. This file is located in web/WEB-INF/classes - open it and add the following:
- I usually add these under the # -- success messages -- comment.
person.added=Person has been added successfully.
person.updated=Person has been updated successfully.
person.deleted=Person has been deleted successfully.
You could use generic added, deleted and updated messages, whatever works for you. It's nice to have separate messages in case these need to change on a per-entity basis.
You might notice that the code we're using to call the PersonManager is the same as the code we used in our PersonManagerTest. Both PersonFormController and PersonManagerTest are clients of PersonManagerImpl, so this makes perfect sense.
Now you need to add a url-mapping for this controller in the web/WEB-INF/action-servlet.xml file. In the block below, the new line is at the bottom, with <prop key="/editPerson.html">:
<bean id="urlMapping"
class="org.springframework.web.servlet.handler.SimpleUrlHandlerMapping">
<property name="mappings">
<props>
<prop key="/editProfile.html">userFormController</prop>
<prop key="/mainMenu.html">filenameController</prop>
<prop key="/editUser.html">userFormController</prop>
<prop key="/selectFile.html">filenameController</prop>
<prop key="/uploadFile.html">fileUploadController</prop>
<prop key="/passwordHint.xml">passwordHintController</prop>
<prop key="/signup.xml">signupController</prop>
<prop key="/editPerson.html">personFormController</prop>
</props>
</property>
</bean>
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You also need to add the <bean> definition for personFormController in this same file:
<bean id="personFormController" class="org.appfuse.webapp.action.PersonFormController">
<property name="commandName"><value>person</value></property>
<property name="commandClass"><value>org.appfuse.model.Person</value></property>
<!--property name="validator"><ref bean="beanValidator"/></property-->
<property name="formView"><value>personForm</value></property>
<property name="successView"><value>mainMenu.html</value></property>
<property name="personManager"><ref bean="personManager"/></property>
</bean>
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- The "validator" property is commented out in the above XML block because we haven't defined any validation rules for the Person object. We'll uncomment this value when we add validation.
If you look at our PersonFormControllerTest, all the tests depend on having a record with id=1 in the database (and testRemove depends on id=2), so let's add those records to our sample data file (metadata/sql/sample-data.xml). I'd just add it at the bottom - order is not important since it (currently) does not relate to any other tables.
<table name='person'>
<column>id</column>
<column>first_name</column>
<column>last_name</column>
<row>
<value>1</value>
<value>Matt</value>
<value>Raible</value>
</row>
<row>
<value>2</value>
<value>James</value>
<value>Davidson</value>
</row>
</table>
DBUnit loads this file before we running any of the tests, so this record will be available to your Controller test.
Make sure are in the base directory of your project. If you run ant test-web -Dtestcase=PersonFormController - everything should work as planned.
BUILD SUCCESSFUL
Total time: 21 seconds
Clean up the JSP to make it presentable
If you want to add a usability enhancement to your form, you can set the cursor to focus on the first field when the page loads. Simply add the following JavaScript at the bottom of your form:
<script type="text/javascript">
document.forms["person"].elements["firstName"].focus();
</script>
Now if you execute ant db-load deploy, start Tomcat and point your browser to http://localhost:8080/appfuse/editPerson.html?id=1, you should see something like this:
Finally, to make this page more user friendly, you may want to add a message for your users at the top of the form, but this can easily be done by adding text (using <fmt:message>) at the top of the personForm.jsp page.
[Optional] Create a Canoo WebTest to test browser-like actions
The final (optional) step in this tutorial is to create a Canoo WebTest to test the JSPs.
- I say this step is optional, because you can run the same tests through your browser.
You can use the following URLs to test the different actions for adding, editing and saving a user.
Canoo tests are pretty slick in that they're simply configured in an XML file. To add tests for add, edit, save and delete, open test/web/web-tests.xml and add the following XML. You'll notice that this fragment has a target named PersonTests that runs all the related tests.
- I use CamelCase target names (vs. the traditional lowercase, dash-separated) because when you're typing -Dtestcase=Name, I've found that I'm used to doing CamelCase for my JUnit Tests.
<!-- runs person-related tests -->
<target name="PersonTests"
depends="EditPerson,SavePerson,AddPerson,DeletePerson"
description="Call and executes all person test cases (targets)">
<echo>Successfully ran all Person JSP tests!</echo>
</target>
<!-- Verify the edit person screen displays without errors -->
<target name="EditPerson"
description="Tests editing an existing Person's information">
<webtest name="editPerson">
&config;
<steps>
&login;
<invoke description="click Edit Person link" url="/editPerson.html?id=1"/>
<verifytitle description="we should see the personDetail title"
text=".*${personDetail.title}.*" regex="true"/>
</steps>
</webtest>
</target>
<!-- Edit a person and then save -->
<target name="SavePerson"
description="Tests editing and saving a user">
<webtest name="savePerson">
&config;
<steps>
&login;
<invoke description="click Edit Person link" url="/editPerson.html?id=1"/>
<verifytitle description="we should see the personDetail title"
text=".*${personDetail.title}.*" regex="true"/>
<setinputfield description="set lastName" name="lastName" value="Canoo"/>
<clickbutton label="Save" description="Click Save"/>
<verifytitle description="Page re-appears if save successful"
text=".*${personDetail.title}.*" regex="true"/>
<verifytext description="verify success message" text="${person.updated}"/>
</steps>
</webtest>
</target>
<!-- Add a new Person -->
<target name="AddPerson"
description="Adds a new Person">
<webtest name="addPerson">
&config;
<steps>
&login;
<invoke description="click Add Button" url="/editPerson.html"/>
<verifytitle description="we should see the personDetail title"
text=".*${personDetail.title}.*" regex="true"/>
<setinputfield description="set firstName" name="firstName" value="Abbie"/>
<setinputfield description="set lastName" name="lastName" value="Raible"/>
<clickbutton label="${button.save}" description="Click button 'Save'"/>
<verifytitle description="Main Menu appears if save successful"
text=".*${mainMenu.title}.*" regex="true"/>
<verifytext description="verify success message" text="${person.added}"/>
</steps>
</webtest>
</target>
<!-- Delete existing person -->
<target name="DeletePerson"
description="Deletes existing Person">
<webtest name="deletePerson">
&config;
<steps>
&login;
<invoke description="click Edit Person link" url="/editPerson.html?id=1"/>
<clickbutton label="${button.delete}" description="Click button 'Delete'"/>
<verifytitle description="display Main Menu" text=".*${mainMenu.title}.*" regex="true"/>
<verifytext description="verify success message" text="${person.deleted}"/>
</steps>
</webtest>
</target>
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After adding this, you should be able to run ant test-canoo -Dtestcase=PersonTests with Tomcat running or ant test-jsp -Dtestcase=PersonTests if you want Ant to start/stop Tomcat for you. To include the PersonTests when all Canoo tests are run, add it as a dependency to the "run-all-tests" target.
You'll notice that there's no logging in the client-side window by Canoo. If you'd like to see what it's doing, you can add the following between </webtest> and </target> at the end of each target.
<loadfile property="web-tests.result"
srcFile="${test.dir}/data/web-tests-result.xml"/>
<echo>${web-tests.result}</echo>
BUILD SUCCESSFUL
Total time: 10 seconds
Next Up: Part IV: Adding Validation and List Screen - Adding validation logic to the personForm so that firstName and lastName are required fields and adding a list screen to display all person records in the database.
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