Java

Convert a MIME Entity to multipart/alternative

Demonstrates the Chilkat Mime.ConvertToMultipartAlt method, which wraps the current entity in a new outer multipart/alternative, making the original the first child. It takes no arguments.

Note: The file paths are relative to the application's current working directory. Absolute paths may also be used. Supply the paths appropriate to your own environment.

Background: Use this to add an alternate rendering to an existing message — for example, promoting a plain-text message so an HTML version can be added alongside it. The original content becomes the first (least-preferred) alternative, and you append the richer representation after it. As with the mixed conversion, message-level headers move to the new outer entity.

Chilkat Java Downloads

Download Chilkat for Java

Java

import com.chilkatsoft.*;

public class ChilkatExample {

  static {
    try {
        System.loadLibrary("chilkat");
    } catch (UnsatisfiedLinkError e) {
      System.err.println("Native code library failed to load.\n" + e);
      System.exit(1);
    }
  }

  public static void main(String argv[])
  {
    boolean success = false;

    CkMime mime = new CkMime();
    success = mime.LoadMimeFile("qa_data/message.eml");
    if (success == false) {
        System.out.println(mime.lastErrorText());
        return;
        }

    //  Wrap the current entity in a new outer multipart/alternative entity.  The original entity
    //  becomes the first child, ready for an alternate representation to be added.
    success = mime.ConvertToMultipartAlt();
    if (success == false) {
        System.out.println(mime.lastErrorText());
        return;
        }

    //  Add an alternative representation of the same content.
    CkMime htmlPart = new CkMime();
    success = htmlPart.SetBodyFromHtml("<html><body>HTML alternative.</body></html>");
    if (success == false) {
        System.out.println(htmlPart.lastErrorText());
        return;
        }

    success = mime.AppendPart(htmlPart);
    if (success == false) {
        System.out.println(mime.lastErrorText());
        return;
        }

    System.out.println("Number of parts: " + mime.get_NumParts());
  }
}