(Android™) The MIME Content-Type Header Field

Explains the ContentType property and the Content-Type header field including the various attributes that may be included.

Chilkat Android™ Downloads Android™ Java Libraries Android C/C++ Libraries

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    // Every part in a MIME messsage should include a Content-Type header field.
    // The Content-Type indicates the type of content contained in the MIME part.
    // For example: text/plain, image/jpeg, application/pdf, application/json, multipart/mixed, etc.

    // Multipart content types are those where the MIME part's body is composed of N inner MIME messages,
    // separated by a boundary string.
    // This is how MIME gets a nested, tree-like structure.  The most common multipart MIME types
    // are (for email related MIME) multipart/mixed, multipart/alternative, and multipart/related,
    // and for HTTP related MIME, it is multipart/form-data.

    boolean success;
    CkMime mime = new CkMime();

    // The Content-Type header field can be set or modified in two ways.
    // 1) By setting the ContentType, Micalg, Name, Charset, Boundary, or Protocol properties.
    //    Setting the ContentType property sets the primary value (such as "text/plain") of the header field.
    //    Each of the other properties listed above will replace or add a particular attribute value.

    // 2) By setting the entire contents of the ContentType header with the SetHeaderField method.
    //    This updates each of the Content-Type related properties.

    // For example:
    mime.put_ContentType("text/plain");
    mime.put_Charset("utf-8");

    // The Content-Type header field contains this:
    //     Content-Type: text/plain; charset=utf-8
    Log.i(TAG, mime.getEntireHead());
    Log.i(TAG, "-");

    mime.SetHeaderField("Content-Type","image/jpeg; name=\"kitty.jpg\"");
    // The Content-Type header field now contains this:
    //     Content-Type: image/jpeg; name="kitty.jpg"
    Log.i(TAG, mime.getEntireHead());
    Log.i(TAG, "-");

    // Notice how the properties have been updated:
    Log.i(TAG, "ContentType property: " + mime.contentType());
    Log.i(TAG, "Charset property: " + mime.charset());
    Log.i(TAG, "Name property: " + mime.name());
    Log.i(TAG, "-");

    // To change a particular attribute value, set the property.
    mime.put_Name("doggy.jpg");
    Log.i(TAG, mime.getEntireHead());
    Log.i(TAG, "-");

    // To remove an attribute value from the Content-Type header,
    // set the property to an empty string.
    mime.put_Name("");
    Log.i(TAG, mime.getEntireHead());
    Log.i(TAG, "-");

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}