Adding Signature Fields

Digital signatures appear in signature fields, which are form fields that contain a graphic representation of the signature. Signature fields can be visible or invisible. Signers can use a preexisting signature field, or a signature field can be programmatically added. In either case, the signature field must exist before a PDF document can be signed.

You can programmatically add a signature field by using the Signature service Java API or Signature web service API. You can add more than one signature field to a PDF document; however, each signature field name must be unique.

Remarque : Some PDF document types do not let you programmatically add a signature field. For more information about the Signature service and adding signature fields, see Services Reference for LiveCycle.

Summary of steps

To add a signature field to a PDF document, perform the following tasks:

  1. Include project files.

  2. Create a Signature client.

  3. Get a PDF document to which a signature field is added.

  4. Add a signature field.

  5. Save the PDF document as a PDF file.

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.

The following JAR files must be added to your project’s classpath:

  • adobe-livecycle-client.jar

  • adobe-usermanager-client.jar

  • adobe-signatures-client.jar

  • adobe-utilities.jar (required if LiveCycle is deployed on JBoss)

  • jbossall-client.jar (required if LiveCycle is deployed on JBoss)

Create a Signature client

Before you can programmatically perform a Signature service operation, you must create a Signature service client.

Get a PDF document to which a signature field is added

You must obtain a PDF document to which a signature field is added.

Add a signature field

To successfully add a signature field to a PDF document, you specify coordinate values that identify the location of the signature field. (If you add an invisible signature field, these values are not required.) Also, you can specify which fields in the PDF document are locked after a signature is applied to the signature field.

Save the PDF document as a PDF file

After the Signature service adds a signature field to the PDF document, you can save the document as a PDF file so that users can open it in Acrobat or Adobe Reader.

Add signature fields using the Java API

Add a signature field by using the Signature API (Java):

  1. Include project files

    Include client JAR files, such as adobe-signatures-client.jar, in your Java project’s classpath.

  2. Create a Signature client

    • Create a ServiceClientFactory object that contains connection properties.

    • Create a SignatureServiceClient object by using its constructor and passing the ServiceClientFactory object.

  3. Get a PDF document to which a signature field is added

    • Create a java.io.FileInputStream object that represents the PDF document to which a signature field is added by using its constructor and passing a string value that specifies the location of the PDF document.

    • Create a com.adobe.idp.Document object by using its constructor and passing the java.io.FileInputStream object.

  4. Add a signature field

    • Create a PositionRectangle object that specifies the signature field location by using its constructor. Within the constructor, specify coordinate values.

    • If desired, create a FieldMDPOptions object that specifies the fields that are locked when a digital signature is applied to the signature field.

    • Add a signature field to a PDF document by invoking the SignatureServiceClient object’s addSignatureField method and passing the following values:

      • A com.adobe.idp.Document object that represents the PDF document to which a signature field is added.

      • A string value that specifies the name of the signature field.

      • A java.lang.Integer value that represents the page number to which a signature field is added.

      • A PositionRectangle object that specifies the location of the signature field.

      • A FieldMDPOptions object that specifies fields in the PDF document that are locked after a digital signature is applied to the signature field. This parameter value is optional, and you can pass null.

    • A PDFSeedValueOptions object that specifies various run-time values. This parameter value is optional, and you can pass null.

      The addSignatureField method returns a com.adobe.idp.Document object that represents a PDF document that contains a signature field.

    Remarque : You can invoke the SignatureServiceClient object’s addInvisibleSignatureField method to add an invisible signature field.
  5. Save the PDF document as a PDF file

    • Create a java.io.File object and ensure that the file extension is .pdf.

    • Invoke the com.adobe.idp.Document object’s copyToFile method to copy the contents of the Document object to the file. Ensure that you use the com.adobe.idp.Document object that was returned by the addSignatureField method.

Add signature fields using the web service API

To add a signature field by using the Signature API (web service):

  1. Include project files

    Create a Microsoft .NET project that uses MTOM. Ensure that you use the following WSDL definition: http://localhost:8080/soap/services/SignatureService?WSDL&lc_version=9.0.1.

    Remarque : Replace localhost with the IP address of the server hosting LiveCycle.
  2. Create a Signature client

    • Create a SignatureServiceClient object by using its default constructor.

    • Create a SignatureServiceClient.Endpoint.Address object by using the System.ServiceModel.EndpointAddress constructor. Pass a string value that specifies the WSDL to the LiveCycle service (for example, http://localhost:8080/soap/services/SignatureService?WSDL). You do not need to use the lc_version attribute. This attribute is used when you create a service reference.)

    • Create a System.ServiceModel.BasicHttpBinding object by getting the value of the SignatureServiceClient.Endpoint.Binding field. Cast the return value to BasicHttpBinding.

    • Set the System.ServiceModel.BasicHttpBinding object’s MessageEncoding field to WSMessageEncoding.Mtom. This value ensures that MTOM is used.

    • Enable basic HTTP authentication by performing the following tasks:

      • Assign the LiveCycle user name to the field SignatureServiceClient.ClientCredentials.UserName.UserName.

      • Assign the corresponding password value to the field SignatureServiceClient.ClientCredentials.UserName.Password.

      • Assign the constant value HttpClientCredentialType.Basic to the field BasicHttpBindingSecurity.Transport.ClientCredentialType.

      • Assign the constant value BasicHttpSecurityMode.TransportCredentialOnly to the field BasicHttpBindingSecurity.Security.Mode.

  3. Get a PDF document to which a signature field is added

    • Create a BLOB object by using its constructor. The BLOB object is used to store the PDF document that will contain a signature field.

    • Create a System.IO.FileStream object by invoking its constructor and passing a string value that represents the file location of the PDF document and the mode in which to open the file.

    • Create a byte array that stores the content of the System.IO.FileStream object. You can determine the size of the byte array by getting the System.IO.FileStream object’s Length property.

    • Populate the byte array with stream data by invoking the System.IO.FileStream object’s Read method and passing the byte array, the starting position, and the stream length to read.

    • Populate the BLOB object by assigning its MTOM property with the contents of the byte array.

  4. Add a signature field

    Add a signature field to the PDF document by invoking the SignatureServiceClient object’s addSignatureField method and passing the following values:

    • A BLOB object that represents the PDF document to which a signature field is added.

    • A string value that specifies the signature field name.

    • An integer value that represents the page number to which a signature field is added.

    • A PositionRect object that specifies the location of the signature field.

    • A FieldMDPOptions object that specifies fields in the PDF document that are locked after a digital signature is applied to the signature field. This parameter value is optional, and you can pass null.

    • A PDFSeedValueOptions object that specifies various run-time values. This parameter value is optional, and you can pass null.

    The addSignatureField method returns a BLOB object that represents a PDF document that contains a signature field.

  5. Save the PDF document as a PDF file

    • Create a System.IO.FileStream object by invoking its constructor and passing a string value that represents the file location of the PDF document that will contain the signature field and the mode in which to open the file.

    • Create a byte array that stores the content of the BLOB object that was returned by the addSignatureField method. Populate the byte array by getting the value of the BLOB object’s binaryData data member.

    • Create a System.IO.BinaryWriter object by invoking its constructor and passing the System.IO.FileStream object.

    • Write the contents of the byte array to a PDF file by invoking the System.IO.BinaryWriter object’s Write method and passing the byte array.