Rendering Interactive PDF Forms

Sample loan application

A sample loan application is introduced to demonstrate how the Forms service uses interactive forms to collect information from users. This application lets a user fill in a form with data required to secure a loan and then submits data to the Forms service. The following diagram shows the loan application’s logic flow.

Grafik in Originalgröße anzeigen

The following table describes the steps in this diagram.

Loan form

This interactive loan form is rendered by the sample loan application’s GetLoanForm Java Servlet.

Grafik in Originalgröße anzeigen

Confirmation form

This form is rendered by the sample loan application’s HandleData Java Servlet.

Grafik in Originalgröße anzeigen

The HandleData Java Servlet prepopulates this form with the user’s first and last name as well as the amount. After the form is prepopulated, it is sent to the client web browser. (See Prepopulating Forms with Flowable Layouts.)

Java Servlets

The sample loan application is an example of a Forms service application that exists as a Java Servlet. A Java Servlet is a Java program running on a J2EE application server, such as WebSphere, and contains Forms service Client API code.

The following code shows the syntax of a Java Servlet named GetLoanForm:

    public class GetLoanForm extends HttpServlet implements Servlet { 
        public void doGet(HttpServletRequest req, HttpServletResponse resp 
        throws ServletException, IOException { 
         
        } 
        public void doPost(HttpServletRequest req, HttpServletResponse resp 
        throws ServletException, IOException { 
             
            }

Normally, you would not place Forms service Client API code within a Java Servlet’s doGet or doPost method. It is better programming practice to place this code within a separate class, instantiate the class from within the doPost method (or doGet method), and call the appropriate methods. However, for code brevity, the code examples in this section are kept to a minimum and code examples are placed in the doPost method.

Summary of steps

To render an interactive PDF form, perform the following tasks:

1. Include project files.

2. Create a Forms Client API object.

3. Specify URI values.

4. Attach files to the form (Optional).

5. Render an interactive PDF form.

6. Write the form data stream to the client web browser.

Include project files

Include necessary files into your development project. If you are creating a client application using Java, include the necessary JAR files. If you are using web services, ensure that you include the proxy files.

Create a Forms Client API object

Before you can programmatically perform a Forms service Client API operation, you must create a Forms Client API object. If you are using the Java API, create a FormsServiceClient object. If you are using the Forms web service API, create a FormsService object.

Specify URI values

You can specify URI values that are required by the Forms service to render a form. A form design that is saved as part of a LiveCycle application can be referenced by using the content root URI value repository:///. For example, consider the following form design named Loan.xdp located within a LiveCycle application named FormsApplication:

Grafik in Originalgröße anzeigen

To access this form design, specify Applications/FormsApplication/1.0/FormsFolder/Loan.xdp as the form name (the first parameter passed to the renderPDFForm method) and repository:/// as the content root URI value.

The path to a resource located in a LiveCycle application is:

Applications/Application-name/Application-version/Folder.../Filename

The following values show some examples of URI values:

• Applications/AppraisalReport/1.0/Forms/FullForm.xdp

• Applications/AnotherApp/1.1/Assets/picture.jpg

• Applications/SomeApp/2.0/Resources/Data/XSDs/MyData.xsd

When you render an interactive form, you can define URI values such as the target URL to where form data is posted. The target URL can be defined in one of the following ways:

• On the Submit button while designing the form design in Designer

• By using the Forms service Client API

If the target URL is defined within the form design, do not override it with the Forms service Client API. That is, setting the target URL using the Forms API resets the specified URL in the form design to the one specified using the API. If you wish to submit the PDF form to the target URL specified in the form design, then programmatically set the target URL to an empty string.

If you have a form that contains a submit button and a calculate button (with a corresponding script that runs at the server), you can programmatically define the URL to where the form is sent to execute the script. Use the submit button on the form design to specify the URL to where form data is posted. (See Calculating Form Data.)

Attach files to the form

You can attach files to a form. When you render a PDF form with file attachments, users can retrieve the file attachments in Acrobat using the file attachment pane. You can attach different file types to a form, such as a text file, or to a binary file such as a JPG file.

Render an interactive PDF form

To render a form, use a form design that was created in Designer and saved as an XDP or PDF file. As well, you can render a form that was created using Acrobat and saved as a PDF file. To render an interactive PDF form, invoke the FormsServiceClient object’s renderPDFForm method or renderPDFForm2 method.

The renderPDFForm uses a URLSpec object. The content root to the XDP file is passed to the Forms service using the URLSpec object’s setContentRootURI method. The Form design name (formQuery) is passed as a separate parameter value. The two values are concatenated to get the absolute reference to the form design.

The renderPDFForm2 method accepts a com.adobe.idp.Document instance that contains the XDP or PDF document to render.