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Posted to commits@struts.apache.org by lu...@apache.org on 2017/07/30 10:25:19 UTC
struts-site git commit: Breaks long lines
Repository: struts-site
Updated Branches:
refs/heads/master 5a7ec7cde -> 6ff7bb27a
Breaks long lines
Project: http://git-wip-us.apache.org/repos/asf/struts-site/repo
Commit: http://git-wip-us.apache.org/repos/asf/struts-site/commit/6ff7bb27
Tree: http://git-wip-us.apache.org/repos/asf/struts-site/tree/6ff7bb27
Diff: http://git-wip-us.apache.org/repos/asf/struts-site/diff/6ff7bb27
Branch: refs/heads/master
Commit: 6ff7bb27adad4558b99895af3295b82c34e6b2ef
Parents: 5a7ec7c
Author: Lukasz Lenart <lu...@apache.org>
Authored: Sun Jul 30 12:25:12 2017 +0200
Committer: Lukasz Lenart <lu...@apache.org>
Committed: Sun Jul 30 12:25:12 2017 +0200
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source/getting-started/processing-forms.md | 89 +++++++++++++++++++------
1 file changed, 67 insertions(+), 22 deletions(-)
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http://git-wip-us.apache.org/repos/asf/struts-site/blob/6ff7bb27/source/getting-started/processing-forms.md
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diff --git a/source/getting-started/processing-forms.md b/source/getting-started/processing-forms.md
index 0f6a7ba..0ff1bc4 100644
--- a/source/getting-started/processing-forms.md
+++ b/source/getting-started/processing-forms.md
@@ -4,21 +4,30 @@ title: Processing forms
---
## Processing Forms
-This tutorial assumes you've completed the [Coding Struts 2 Actions](coding-actions.html) tutorial and have a working coding-actions project. The example code for this tutorial, form-processing, is available for checkout from the Struts 2 GitHub subversion repository: [https://github.com/apache/struts-examples](https://github.com/apache/struts-examples).
+This tutorial assumes you've completed the [Coding Struts 2 Actions](coding-actions.html) tutorial and have a working
+coding-actions project. The example code for this tutorial, form-processing, is available for checkout from
+the Struts 2 GitHub subversion repository: [https://github.com/apache/struts-examples](https://github.com/apache/struts-examples).
### Introduction
-In this tutorial we'll explore using Struts 2 to do more involved processing of a form submission. We'll cover how to use a Java model class to store the form input and how to create the Struts 2 form to match up with that model class.
+In this tutorial we'll explore using Struts 2 to do more involved processing of a form submission. We'll cover how to
+use a Java model class to store the form input and how to create the Struts 2 form to match up with that model class.
-The code provided in this tutorial may be added to the [Coding Struts 2 Actions](coding-actions.html) example or you can download this complete example from the github respository - [https://github.com/apache/struts-examples](https://github.com/apache/struts-examples).
+The code provided in this tutorial may be added to the [Coding Struts 2 Actions](coding-actions.html) example or you
+can download this complete example from the github respository - [https://github.com/apache/struts-examples](https://github.com/apache/struts-examples).
-The [Struts 2 user mailing list](http://struts.apache.org/mail.html) is an excellent place to get help. If you are having a problem getting the tutorial example applications to work search the Struts 2 mailing list. If you don't find an answer to your problem, post a question on the mailing list.
+The [Struts 2 user mailing list](http://struts.apache.org/mail.html) is an excellent place to get help. If you are
+having a problem getting the tutorial example applications to work search the Struts 2 mailing list. If you don't find
+an answer to your problem, post a question on the mailing list.
### Forms and a Java model class
-For this tutorial let's say we need to provide a form that a user may submit to register for a prize drawing. Our business rules state the user must provide his/her first name, last name, email address, and age.
+For this tutorial let's say we need to provide a form that a user may submit to register for a prize drawing. Our
+business rules state the user must provide his/her first name, last name, email address, and age.
-To encapsulate this data, we'll use a simple Java class that follows the basic Java Bean specifications (public set/get methods for each instance field). If you're following along add this class to the package `org.apache.struts.register.model` in the [Coding Struts 2 Actions](coding-actions.html) example.
+To encapsulate this data, we'll use a simple Java class that follows the basic Java Bean specifications (public set/get
+methods for each instance field). If you're following along add this class to the package `org.apache.struts.register.model`
+in the [Coding Struts 2 Actions](coding-actions.html) example.
**Person.java**
@@ -68,11 +77,16 @@ public class Person {
}
```
-Note a few points about the above class. There is a public set/get method for each instance field. The age attribute is of type integer. We've defined a public `toString` method that returns a String representing the state of the object. Since we haven't specified a constructor, Java will provide a default constructor that will set all instance fields to their null values.
+Note a few points about the above class. There is a public set/get method for each instance field. The age attribute
+is of type integer. We've defined a public `toString` method that returns a String representing the state of the object.
+Since we haven't specified a constructor, Java will provide a default constructor that will set all instance fields to
+their null values.
### Form structure
-To collect the above information we'll use a Struts 2 form. When creating this form the key concept we need to employ is to tie each form field to a specific instance field of an object of type Person. Let's look over the form first and then discuss some key points. Create a view page named `register.jsp` (in `src/main/webapp`)
+To collect the above information we'll use a Struts 2 form. When creating this form the key concept we need to employ
+is to tie each form field to a specific instance field of an object of type Person. Let's look over the form first and
+then discuss some key points. Create a view page named `register.jsp` (in `src/main/webapp`)
**register.jsp**
@@ -103,15 +117,24 @@ Since we are using Struts 2 tags, at the top of the page we need the Struts tag
The Struts 2 form will submit to an action named register. We'll need to define that action in our `struts.xml` file.
-Note the four Struts 2 textfield tags. Each tag has a name value that includes an attribute of the `Person` class (e.g. `firstName`). The name attribute's value also has a reference to an object called `personBean`. This object is of type `Person`. When we create the Action class that handles this form submission, we'll have to specify that object in that Action class (see below).
+Note the four Struts 2 textfield tags. Each tag has a name value that includes an attribute of the `Person` class
+(e.g. `firstName`). The name attribute's value also has a reference to an object called `personBean`. This object is
+of type `Person`. When we create the Action class that handles this form submission, we'll have to specify that object
+in that Action class (see below).
-The complete name value, `personBean.firstName`, instructs Struts 2 to use the input value for that textfield as the argument to the personBean object's `setFirstName` method. So if the user types "Bruce" in the textfield that has the label "First name", the personBean's `firstName` instance field will have a value of "Bruce".
+The complete name value, `personBean.firstName`, instructs Struts 2 to use the input value for that textfield as
+the argument to the personBean object's `setFirstName` method. So if the user types "Bruce" in the textfield that has
+the label "First name", the personBean's `firstName` instance field will have a value of "Bruce".
-Note that we have a Struts 2 textfield for each instance field of the class Person. Remember that Person class's age attribute is of type integer. All form field input values are Strings. Struts 2 will automatically convert the String value ("25") the user entered for the age form field to 25 when calling the `setAge` method of object `personBean`.
+Note that we have a Struts 2 textfield for each instance field of the class Person. Remember that Person class's age
+attribute is of type integer. All form field input values are Strings. Struts 2 will automatically convert the String
+value ("25") the user entered for the age form field to 25 when calling the `setAge` method of object `personBean`.
### Creating the Action class to handle the form submission
-When the user clicks on the submit button of the above form, the action "register" and the form data will be sent to the Struts 2 framework. We need an Action class to process this form. If you recall from the tutorial [Coding Struts 2 Actions](coding-actions.html) our Action class should extend the Struts 2 ActionSupport class.
+When the user clicks on the submit button of the above form, the action "register" and the form data will be sent to
+the Struts 2 framework. We need an Action class to process this form. If you recall from the tutorial
+[Coding Struts 2 Actions](coding-actions.html) our Action class should extend the Struts 2 ActionSupport class.
Here is the Action class used for this example. Place it in package org.apache.struts.register.action.
@@ -147,19 +170,32 @@ public class Register extends ActionSupport {
}
```
-In the `Register` class note that we've declared an attribute named `personBean` of type `Person` and there is a public get and set method for this object.
+In the `Register` class note that we've declared an attribute named `personBean` of type `Person` and there is a public
+get and set method for this object.
-The `Register` class also overrides the `execute` method. The `execute` method is the one we will specify in the `struts.xml` to be called in response to the register action. In this example, the `execute` method just returns the String constant `SUCCESS` (inherited from the `ActionSupport` class). But in a real application, within the `execute` method we would call upon other classes (Service objects) to perform the business processing of the form, such as storing the user's input into a data repository.
+The `Register` class also overrides the `execute` method. The `execute` method is the one we will specify in the
+`struts.xml` to be called in response to the register action. In this example, the `execute` method just returns
+the String constant `SUCCESS` (inherited from the `ActionSupport` class). But in a real application, within the `execute`
+method we would call upon other classes (Service objects) to perform the business processing of the form, such as storing
+the user's input into a data repository.
-The `personBean` object of type `Person` declared in the Register Action class matches the `personBean` name we used in the form's textfields. When the form is submitted, the Struts 2 framework will inspect the Action class and look for an object named `personBean`. It will create that object using the `Person` class's default constructor. Then for each form field that has a name value of personBean.someAttribute (e.g `personBean.firstName`) it will call the personBean's public set method for that attribute and pass it the form field's value (the user input). This all happens before the execute method occurs.
+The `personBean` object of type `Person` declared in the Register Action class matches the `personBean` name we used in
+the form's textfields. When the form is submitted, the Struts 2 framework will inspect the Action class and look for
+an object named `personBean`. It will create that object using the `Person` class's default constructor. Then for each
+form field that has a name value of personBean.someAttribute (e.g `personBean.firstName`) it will call the personBean's
+public set method for that attribute and pass it the form field's value (the user input). This all happens before
+the execute method occurs.
-When Struts 2 runs the `execute` method of class `Register`, the `personBean` object in class `Register` now has values for its instance fields that are equal to the values the user entered into the corresponding form fields.
+When Struts 2 runs the `execute` method of class `Register`, the `personBean` object in class `Register` now has values
+for its instance fields that are equal to the values the user entered into the corresponding form fields.
-By using a Java model class to encapsulate the data provided by the form we don't have to have a separate attribute (with public set/get methods) in the Action class (Register) for each form field.
+By using a Java model class to encapsulate the data provided by the form we don't have to have a separate attribute
+(with public set/get methods) in the Action class (Register) for each form field.
### Adding the view for the result
-When `SUCCESS` is returned by the `execute` method we want to display a simple thank you page that shows the user's registration. Add the `thankyou.jsp` below to `src/main/webapp`.
+When `SUCCESS` is returned by the `execute` method we want to display a simple thank you page that shows the user's
+registration. Add the `thankyou.jsp` below to `src/main/webapp`.
**thankyou.jsp**
@@ -186,7 +222,9 @@ If you don't recall how the Struts 2 property and url tags work consult the [Usi
### Create action mapping in struts.xml
-To specify the relationship between the form submission page, the Struts 2 Action class, and the success view page we need to add an action node to `struts.xml`. Add this action node to `struts.xml` (`src/main/resources`) after the hello action and before the closing package node.
+To specify the relationship between the form submission page, the Struts 2 Action class, and the success view page
+we need to add an action node to `struts.xml`. Add this action node to `struts.xml` (`src/main/resources`) after
+the hello action and before the closing package node.
**action node for struts.xml**
@@ -196,9 +234,12 @@ To specify the relationship between the form submission page, the Struts 2 Actio
</action>
```
-The above action tells Struts 2 that when the register action is provided to call method `execute` of class `Register`. If that method returns result "success" return to the browser the `thankyou.jsp`.
+The above action tells Struts 2 that when the register action is provided to call method `execute` of class `Register`.
+If that method returns result "success" return to the browser the `thankyou.jsp`.
-Note that we don't need to tell Struts 2 anything about processing the form. The transfer of the form field input values to the `personBean` object will happen automatically provided we've followed the convention of naming our form fields to match personBean.attributeName (e.g. `personBean.lastName`).
+Note that we don't need to tell Struts 2 anything about processing the form. The transfer of the form field input values
+to the `personBean` object will happen automatically provided we've followed the convention of naming our form fields
+to match personBean.attributeName (e.g. `personBean.lastName`).
### Create a link to register.jsp
@@ -212,7 +253,11 @@ So that the user can find the registration page, add this link to index.jsp
__Run The Example__
-If everything is correct, you should be able to run the application (using `mvn jetty:run`), and open this URL in your web browser: [http://localhost:8080/form-processing/index.action](http://localhost:8080/form-processing/index.action). On that page should be a link to register. Click on that link and you should see the `register.jsp` page.
+If everything is correct, you should be able to run the application (using `mvn jetty:run`), and open this URL in your
+web browser:
+[http://localhost:8080/form-processing/index.action](http://localhost:8080/form-processing/index.action). On that page
+should be a link to register.
+Click on that link and you should see the `register.jsp` page.
