developing a Struts2 application
When developing a Struts2 application, there are several best practices to follow to ensure efficiency, maintainability, and security. Here are some key practices along with explanations and a Java example where applicable:
Table of Contents
1. Â Use of Struts2 Actions
Actions in Struts2 are responsible for handling requests from the user. It’s crucial to keep actions simple, focused on a single task, and follow the RESTful principles if possible.
java
package com.example.actions;
import com.opensymphony.xwork2.ActionSupport;
public class HelloAction extends ActionSupport {
private String message;
public String execute() {
message = "Hello, Struts2!";
return SUCCESS;
}
public String getMessage() {
return message;
}
}
2. Â Validation and Error Handling
Struts2 provides built-in validation mechanisms that should be utilized to validate user input and handle errors gracefully.
java
package com.example.actions;
import com.opensymphony.xwork2.ActionSupport;
import org.apache.struts2.convention.annotation.Action;
import org.apache.struts2.convention.annotation.Result;
import org.apache.struts2.convention.annotation.Results;
@Results({
@Result(name = "input", location = "/WEB-INF/content/form.jsp")
})
public class MyAction extends ActionSupport {
private String name;
@Action(value = "/submit")
public String execute() {
if (name == null || name.isEmpty()) {
addActionError("Name is required.");
return INPUT;
}
return SUCCESS;
}
public void setName(String name) {
this.name = name;
}
}
3. Â Avoid Business Logic in Actions
Actions should primarily delegate business logic to service or helper classes to keep them reusable and testable.
java
public class MyAction extends ActionSupport {
private UserService userService;
private User user;
public String execute() {
user = userService.findUserById(userId);
return SUCCESS;
}
// Getter and Setter for userService
// Getter for user
}
4. Â Use of Struts2 Interceptors
Interceptors in Struts2 allow you to perform tasks such as validation, logging, or security checks before and after the execution of an action.
xml
<interceptors>
<interceptor name="customInterceptor" class="com.example.interceptors.CustomInterceptor"/>
<interceptor-stack name="customStack">
<interceptor-ref name="customInterceptor"/>
<interceptor-ref name="defaultStack"/>
</interceptor-stack>
</interceptors>
<action name="myAction" class="com.example.actions.MyAction">
<interceptor-ref name="customStack"/>
<result>/WEB-INF/content/result.jsp</result>
</action>
5. Â Configuration Management
Maintain clean and organized configuration files (struts.xml) by using modularization and parameterization where appropriate.
xml
<action name="myAction" class="com.example.actions.MyAction">
<result>/WEB-INF/content/result.jsp</result>
</action>
6. Â Testing
Implement unit tests for actions, validators, and any custom interceptors to ensure functionality and detect issues early.
java
public class MyActionTest {
@Test
public void testExecute() throws Exception {
MyAction action = new MyAction();
action.setUserService(new MockUserService()); // Mock dependency
action.setUserId(1); // Set required parameters
String result = action.execute();
assertEquals("success", result);
}
}
Following these best practices helps in developing robust and maintainable Struts2 applications. Each practice contributes to better code organization, performance, and security.