Jan 02, 2016 action can be simply forwarded to one page to another view page without using controller, take a look at this simple example. The next step after executing the business logic is to display the view using the results tag. The action is responsible for executing the business logic. The view part of struts 2 is highly configurable and it supports. Learn how to upload a file in struts 2 with the help of the builtin fileuploadinterceptor.
Examples on how to download a file from struts2 with annotations only. Ok, what that means in basic terms is that in the response that is sent back to the. This is the method where we define the behavior of the current action. Heres an example that shows how to define this result type inside an element in struts. Results and result types in the previous chapter, we looked at struts 2 actions and some of the functionality provided by the actionsupport class. Struts 2 default location for result pages are webinfcontent and we are overriding it with struts. It uses and extends the java servlet api to encourage developers to adopt a. Mar 12, 2012 struts 2 struts2 also comes with power apis to configure interceptors that reduce greatly the coupling in application. This chapter will introduce you to all the results and its types used in struts 2 web application development. This result type is used in tag for different actions. A struts 2 example to show the use of custom result type to allow user to download file.
Result types apache struts 2 wiki apache software foundation. I hope this quick solution will save someones time. The following example shows how to integrate struts 2 and tiles using the struts2 tiles plugin. In this action excluding the execute method we can write our own user defined methods.
You will also see how to validate a file based on the file size and the. In this chapter, we selection from apache struts 2 web application development book. In this example you will learn how to do file upload with the help of the builtin fileuploadinterceptor. Redirecting an action looses the current value stack anything in request scope you can of course set up your action to preserve these values by passing them as parameters to. But the action also serves in two other important capacities. The action class manages the applications state, and the result type manages the view. Ok, what that means in basic terms is that in the response that is sent back to the client, the response is the javascript object that represents the action class, and the attributes of the javascipt object are actually named after the public. Results and result types apache struts 2 web application. In a secure application, a client might try to access a page without being authorized, and many actions may need access to a logon result. Create dynamic web project named struts2firstproject.
Struts comes with a number of predefined result types and whatever weve already seen that was the default result type dispatcher, which is used to dispatch to jsp pages. Struts 2 provides efficient way to support file uploads. Also the struts config file has only one forward path corresponding to the uploadaction. Very useful for allowing users to download content.
It uses and extends the java servlet api to encourage developers to adopt a modelviewcontroller mvc architecture. In the deployment descriptor first setup the tiles definition file. A lot of predefined validators and ability to create and plug in custom validators adds to the validation prowess of the framework. In this tutorial, you will create a jsp page with file upload component, set the maximum size and allow content type of the upload file, and display the uploaded file details. The parameters are same given by struts framework mapping,form,request,response. Remove the action tag and user result name as success to redirect to view page without using controller.
Apache struts 2 is an opensource web application framework for developing java ee web applications. Stream result apache struts 2 wiki apache software. The view part of struts 2 is highly configurable and it supports different result types such as velocity, freemarker, jsp, etc. Redirect action result apache struts apache software. The action download must check some validations before download all size, number of files and this possible message errors must to be in the same popup, for this reason i tried to change the targets based on action result name. No result defined for action and result input, struts2 404 error, fix for no result defined for action and result input, struts 2 input result success name. Easy steps to learn struts 2 struts2 application in eclipse.
Struts dispatchaction can group similar action classes into a single action class having different methods. Struts 2 actions actions are the core of the struts2 framework, as they are for any mvc model. The struts 2 json plugin allows you to create an action that can be serialized into a json object. Result interface, ready to use in your own applications. Aug 23, 20 the struts 2 json plugin allows you to create an action that can be serialized into a json object. Additional result types can be created and plugged into an application by implementing the com.
In struts 2 framework, we provide all the components view. Stream result, used to stream an inputstream back to the browser usually for file downloads. Explain various action classes used in struts framework. There are two options with action tag, if the value for the.
Struts allow you to use other markup languages for the view technology to present the results and popular choices include velocity, freemaker, xslt and tiles. Each method of an action class can be fetched by a separate url. Aug 26, 2015 download netbeans struts2 plugin for free. Action the basic action class in which we implement our business logic. Struts 2 no result defined for action and result input. In struts 2, action class is pojo plain old java object pojo means you are not forced to implement any interface or extend any class. Each url is mapped to a specific action, which provides the processing logic which is necessary to service the request from the user. We have following types of action classes in struts. This data is held within the actioncontext objects which makes use of the threadlocal for retrieving the values specific to any specific client request thread. Dec 22, 2009 unlike struts, struts 2 action class are plain pojo objects thus simplifying the testing of the code. Struts 1 supports only one result type that is jsp while struts 2 supports many other result types like jsp, xml, velocity, freemarker etc.
In the chain result type, the target resource will be any action which is already configured in struts. Generally, execute method should be specified that represents. Struts 2 provides support for both serverside and clientside. It is the process of embedding an external dependency into the application component.
The framework provides several implementations of the com. For configuring struts 2 in your eclipse ide please refer configuring struts 2 link. First, we need to change or query the applications state, and then we need to present an updated view of the application. There are a few things that need to be done in order to use json with struts 2.
Struts 2 is slightly different from a traditional mvc framework in that the action takes the role of the model rather than the controller, although there is some. Valuestack in struts2 framework is the storage area where the entire applications data is stored for processing a request. Contribute to apachestruts site development by creating an account on github. Each url is mapped to a specific action, which provides the processing logic which is. In struts 2, the tag is used to create a html file upload component to allow users select file from their local disk and upload it to the server. Struts 2 tutorial one stop solution for beginners edureka. Jul 01, 2016 a struts 2 example to show the use of custom result type to allow user to download file. Jul 28, 20 struts comes with a number of predefined result types and whatever weve already seen that was the default result type dispatcher, which is used to dispatch to jsp pages. Most often, results are nested with the action element. Firstly, the action plays an important role in the transfer of data from the request through to the view, whether its a jsp or other type of result.
For json, you will require a new result type, because. As we see in the above example that if the class extends the basic action class it should override the execute method. As mentioned previously, the results tag plays the role of a view in the struts2 mvc framework. Unlike struts, struts 2 action class are plain pojo objects thus simplifying the testing of the code. Action in action class, declared an inputstream data type and its getter method. The reason is that input is the default result returned by struts 2 whenever there is a problem with validating the parameters passed to an action. Struts 2 supports annotation based configuration and we can use it to create action classes. In this action excluding the execute method we can write our own user. The action download must check some validations before download all size, number of files and this possible message errors must to be in the same popup, for this reason i tried to change the. It is available in a full distribution, or as separate library, source, example and documentation distributions. Struts2 also comes with power apis to configure interceptors that reduce greatly the. And the target view page will be displayed after last action. Struts 2 action tag is helpful for executing an action and inserting the result in a particular location of the web page.
Stream result apache struts 2 wiki apache software foundation. In my struts 2 project when using redirect action i m loosing all my values such as action. Repack of struts2 support plugin available for netbeans version 6. This is a special form of inversion of control which is not supported in struts 1.
To use struts 2 annotations, we need to add struts2conventionplugin. Remove the action tag and user result name as success to. When to use redirect and chain result types in struts2. Struts 2 provides support for both serverside and clientside validation. Heres an example that shows how to define this result type inside an action element in struts. Repack of struts2 support plugin available for netbeans version. This data is held within the actioncontext objects which makes. Struts 2 struts2 also comes with power apis to configure interceptors that reduce greatly the coupling in application. Struts2 also comes with power apis to configure interceptors that reduce greatly the coupling in application. Easy steps to learn struts 2 difference between struts and spring apache struts 2. Learn how to integrate struts 2 and tiles using the struts2 tiles plugin. It is also possible that more than one url pattern can point a single point of execution.
The struts2 validation framework is one of the most comprehensive ones that struts 2 core is composed of. Errors can be displayed on ui which is required by the user. To use struts 2 annotations, we need to add struts2conventionplugin library in the classpath and in web. Actions are the core of the struts2 framework, as they are for any mvc model view controller framework. Custom result types might include generating an email or jms message, generating images, and so forth. You will also see how to validate a file based on the file size and the content type. Action can be simply forwarded to one page to another view page without using controller, take a look at this simple example. Also note that we have define a new action customerform. This facility provides the power to hide package name in url. Jun 29, 2010 in struts 2, the tag is used to create a html file upload component to allow users select file from their local disk and upload it to the server. Generally, execute method should be specified that represents the business logic. Results and result types in struts 2 struts tutorial by. Basically, struts provides you with a few result types.