Java

Convert a MIME Entity to multipart/mixed

Demonstrates the Chilkat Mime.ConvertToMultipartMixed method, which wraps the current entity in a new outer multipart/mixed, 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: This is how you turn an existing single-part message into one that can hold attachments — rather than rebuilding it, you wrap it, and its content becomes the first child of a new multipart/mixed. Message-level and custom headers are carried onto the new outer entity so the message identity is preserved. Afterward, AppendPartFromFile adds attachments beside the original body.

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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/mixed entity.  The original entity becomes the
    //  first child, which is what you do to add attachments to an existing single-part message.
    success = mime.ConvertToMultipartMixed();
    if (success == false) {
        System.out.println(mime.lastErrorText());
        return;
        }

    //  Now attachments can be appended alongside the original content.
    success = mime.AppendPartFromFile("qa_data/report.pdf");
    if (success == false) {
        System.out.println(mime.lastErrorText());
        return;
        }

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