Note that the "class" attribute of the bean "personAction" is set to the name of the action class, and the "personService" bean will be passed as a parameter to the action constructor. Change the "url", "username" and "password" in the "dataSource" bean to the appropiate values for your database. For more details on the rest of the beans on this file, see Springs documentation. The "scope" attribute is new in Spring 2, and it means that Spring will create a new PersonAction object every time an object of that type is requested. In Struts 2 a new action object is created to serve each request, thats why we need scope="prototype".
Struts
We will now create a simple Struts action that wraps PersonServices methods, and we will configure Struts to use Spring as the object factory.
- Open the new class dialog (File -> New -> Class) and enter "PersonAction" for the classname, and "quickstart.action" for the namespace. Set its content to:
java>package quickstart.action;
import java.util.List;
import quickstart.model.Person;
import quickstart.service.PersonService;
import com.opensymphony.xwork2.Action;
import com.opensymphony.xwork2.Preparable;
public class PersonAction implements Preparable {
private PersonService service;
private List<Person> persons;
private Person person;
private Integer id;
public PersonAction(PersonService service) {
this.service = service;
}
public String execute() {
this.persons = service.findAll();
return Action.SUCCESS;
}
public String save() {
this.service.save(person);
this.person = new Person();
return execute();
}
public String remove() {
service.remove(id);
return execute();
}
public List<Person> getPersons() {
return persons;
}
public Integer getId() {
return id;
}
public void setId(Integer id) {
this.id = id;
}
public void prepare() throws Exception {
if (id != null)
person = service.find(id);
}
public Person getPerson() {
return person;
}
public void setPerson(Person person) {
this.person = person;
}
}
Look mom my action is a simple POJO!
The "Preparable" interface instructs Struts to call the "prepare" method if the "PrepareInterceptor" is applied to the action (by default, it is). The constructor of the action takes a "PersonService" as a parameter, which Spring will take care of passing when the action is instatiated.
- Create a new file named "struts.xml" under the "src" folder. And set its content to:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<constant name="struts.objectFactory" value="spring" />
<constant name="struts.devMode" value="true" />
<package name="person" extends="struts-default">
<action name="list" method="execute" class="personAction">
<result>pages/list.jsp</result>
<result name="input">pages/list.jsp</result>
</action>
<action name="remove" class="personAction" method="remove">
<result>pages/list.jsp</result>
<result name="input">pages/list.jsp</result>
</action>
<action name="save" class="personAction" method="save">
<result>pages/list.jsp</result>
<result name="input">pages/list.jsp</result>
</action>
</package>
</struts>
Setting "struts.objectFactory" to "spring" will force Struts to instantiate the actions using Spring, injecting all the defined dependencies on applicationContext.xml. The "class" attribute for each action alias is set to "personAction", which is the bean id that we defined on applicationContext.xml for the PersonAction class. This is all that is needed to make Struts work with Spring.
The pages
We only have two pages, "index.jsp" and "list.jsp". "list.jsp" returns a table with a list of the persons on the database.We have this list on a different page because we are going to add some AJAX to spicy it up.
- Create a new file named "list.jsp" under /WebContent/pages/ and set its content to:
<%@ taglib prefix="s" uri="/struts-tags"%>
<p>Persons</p>
<s:if test="persons.size > 0">
<table>
<s:iterator value="persons">
<tr id="row_<s:property value="id"/>">
<td>
<s:property value="firstName" />
</td>
<td>
<s:property value="lastName" />
</td>
<td>
<s:url id="removeUrl" action="remove">
<s:param name="id" value="id" />
</s:url>
<s:a href="%{removeUrl}" theme="ajax" targets="persons">Remove</s:a>
<s:a id="a_%{id}" theme="ajax" notifyTopics="/edit">Edit</s:a>
</td>
</tr>
</s:iterator>
</table>
</s:if>
This is going to render a table with each row showing the first and last name of the person, a link to remove the person, and a link to edit. The remove link has the attribute "targets", set to "persons", which means that when the user clicks on it, an asynchronous request will be made to the "remove" action (as configured on struts.xml, "remove" points to the "remove" method in PersonAction), passing the person id as parameter.
