Class MimeMultipart

java.lang.Object
jakarta.mail.Multipart
jakarta.mail.internet.MimeMultipart

public class MimeMultipart extends Multipart
The MimeMultipart class is an implementation of the abstract Multipart class that uses MIME conventions for the multipart data.

A MimeMultipart is obtained from a MimePart whose primary type is "multipart" (by invoking the part's getContent() method) or it can be created by a client as part of creating a new MimeMessage.

The default multipart subtype is "mixed". The other multipart subtypes, such as "alternative", "related", and so on, can be implemented as subclasses of MimeMultipart with additional methods to implement the additional semantics of that type of multipart content. The intent is that service providers, mail JavaBean writers and mail clients will write many such subclasses and their Command Beans, and will install them into the JavaBeans Activation Framework, so that any Jakarta Mail implementation and its clients can transparently find and use these classes. Thus, a MIME multipart handler is treated just like any other type handler, thereby decoupling the process of providing multipart handlers from the Jakarta Mail API. Lacking these additional MimeMultipart subclasses, all subtypes of MIME multipart data appear as MimeMultipart objects.

An application can directly construct a MIME multipart object of any subtype by using the MimeMultipart(String subtype) constructor. For example, to create a "multipart/alternative" object, use new MimeMultipart("alternative").

The mail.mime.multipart.ignoremissingendboundary property may be set to false to cause a MessagingException to be thrown if the multipart data does not end with the required end boundary line. If this property is set to true or not set, missing end boundaries are not considered an error and the final body part ends at the end of the data.

The mail.mime.multipart.ignoremissingboundaryparameter System property may be set to false to cause a MessagingException to be thrown if the Content-Type of the MimeMultipart does not include a boundary parameter. If this property is set to true or not set, the multipart parsing code will look for a line that looks like a bounary line and use that as the boundary separating the parts.

The mail.mime.multipart.ignoreexistingboundaryparameter System property may be set to true to cause any boundary to be ignored and instead search for a boundary line in the message as with mail.mime.multipart.ignoremissingboundaryparameter.

Normally, when writing out a MimeMultipart that contains no body parts, or when trying to parse a multipart message with no body parts, a MessagingException is thrown. The MIME spec does not allow multipart content with no body parts. The mail.mime.multipart.allowempty System property may be set to true to override this behavior. When writing out such a MimeMultipart, a single empty part will be included. When reading such a multipart, a MimeMultipart will be created with no body parts.

  • Field Details

    • ds

      protected DataSource ds
      The DataSource supplying our InputStream.
    • parsed

      protected boolean parsed
      Have we parsed the data from our InputStream yet? Defaults to true; set to false when our constructor is given a DataSource with an InputStream that we need to parse.
    • complete

      protected boolean complete
      Have we seen the final bounary line?
      Since:
      JavaMail 1.5
    • preamble

      protected String preamble
      The MIME multipart preamble text, the text that occurs before the first boundary line.
      Since:
      JavaMail 1.5
    • ignoreMissingEndBoundary

      protected boolean ignoreMissingEndBoundary
      Flag corresponding to the "mail.mime.multipart.ignoremissingendboundary" property, set in the initializeProperties() method called from constructors and the parse method.
      Since:
      JavaMail 1.5
    • ignoreMissingBoundaryParameter

      protected boolean ignoreMissingBoundaryParameter
      Flag corresponding to the "mail.mime.multipart.ignoremissingboundaryparameter" property, set in the initializeProperties() method called from constructors and the parse method.
      Since:
      JavaMail 1.5
    • ignoreExistingBoundaryParameter

      protected boolean ignoreExistingBoundaryParameter
      Flag corresponding to the "mail.mime.multipart.ignoreexistingboundaryparameter" property, set in the initializeProperties() method called from constructors and the parse method.
      Since:
      JavaMail 1.5
    • allowEmpty

      protected boolean allowEmpty
      Flag corresponding to the "mail.mime.multipart.allowempty" property, set in the initializeProperties() method called from constructors and the parse method.
      Since:
      JavaMail 1.5
  • Constructor Details

    • MimeMultipart

      public MimeMultipart()
      Default constructor. An empty MimeMultipart object is created. Its content type is set to "multipart/mixed". A unique boundary string is generated and this string is setup as the "boundary" parameter for the contentType field.

      MimeBodyParts may be added later.

    • MimeMultipart

      public MimeMultipart(String subtype)
      Construct a MimeMultipart object of the given subtype. A unique boundary string is generated and this string is setup as the "boundary" parameter for the contentType field. Calls the initializeProperties() method.

      MimeBodyParts may be added later.

      Parameters:
      subtype - the MIME content subtype
    • MimeMultipart

      public MimeMultipart(BodyPart... parts) throws MessagingException
      Construct a MimeMultipart object of the default "mixed" subtype, and with the given body parts. More body parts may be added later.
      Parameters:
      parts - the body parts
      Throws:
      MessagingException - for failures
      Since:
      JavaMail 1.5
    • MimeMultipart

      public MimeMultipart(String subtype, BodyPart... parts) throws MessagingException
      Construct a MimeMultipart object of the given subtype and with the given body parts. More body parts may be added later.
      Parameters:
      subtype - the MIME content subtype
      parts - the body parts
      Throws:
      MessagingException - for failures
      Since:
      JavaMail 1.5
    • MimeMultipart

      public MimeMultipart(DataSource ds) throws MessagingException
      Constructs a MimeMultipart object and its bodyparts from the given DataSource.

      This constructor handles as a special case the situation where the given DataSource is a MultipartDataSource object. In this case, this method just invokes the superclass (i.e., Multipart) constructor that takes a MultipartDataSource object.

      Otherwise, the DataSource is assumed to provide a MIME multipart byte stream. The parsed flag is set to false. When the data for the body parts are needed, the parser extracts the "boundary" parameter from the content type of this DataSource, skips the 'preamble' and reads bytes till the terminating boundary and creates MimeBodyParts for each part of the stream.

      Parameters:
      ds - DataSource, can be a MultipartDataSource
      Throws:
      ParseException - for failures parsing the message
      MessagingException - for other failures
  • Method Details

    • initializeProperties

      protected void initializeProperties()
      Initialize flags that control parsing behavior, based on System properties described above in the class documentation.
      Since:
      JavaMail 1.5
    • setSubType

      public void setSubType(String subtype) throws MessagingException
      Set the subtype. This method should be invoked only on a new MimeMultipart object created by the client. The default subtype of such a multipart object is "mixed".

      Parameters:
      subtype - Subtype
      Throws:
      MessagingException - for failures
    • getCount

      public int getCount() throws MessagingException
      Return the number of enclosed BodyPart objects.
      Overrides:
      getCount in class Multipart
      Returns:
      number of parts
      Throws:
      MessagingException - for failures
      See Also:
    • getBodyPart

      public BodyPart getBodyPart(int index) throws MessagingException
      Get the specified BodyPart. BodyParts are numbered starting at 0.
      Overrides:
      getBodyPart in class Multipart
      Parameters:
      index - the index of the desired BodyPart
      Returns:
      the Part
      Throws:
      MessagingException - if no such BodyPart exists
    • getBodyPart

      public BodyPart getBodyPart(String CID) throws MessagingException
      Get the MimeBodyPart referred to by the given ContentID (CID). Returns null if the part is not found.
      Parameters:
      CID - the ContentID of the desired part
      Returns:
      the Part
      Throws:
      MessagingException - for failures
    • removeBodyPart

      public boolean removeBodyPart(BodyPart part) throws MessagingException
      Remove the specified part from the multipart message. Shifts all the parts after the removed part down one.
      Overrides:
      removeBodyPart in class Multipart
      Parameters:
      part - The part to remove
      Returns:
      true if part removed, false otherwise
      Throws:
      MessagingException - if no such Part exists
      IllegalWriteException - if the underlying implementation does not support modification of existing values
    • removeBodyPart

      public void removeBodyPart(int index) throws MessagingException
      Remove the part at specified location (starting from 0). Shifts all the parts after the removed part down one.
      Overrides:
      removeBodyPart in class Multipart
      Parameters:
      index - Index of the part to remove
      Throws:
      IndexOutOfBoundsException - if the given index is out of range.
      IllegalWriteException - if the underlying implementation does not support modification of existing values
      MessagingException - for other failures
    • addBodyPart

      public void addBodyPart(BodyPart part) throws MessagingException
      Adds a Part to the multipart. The BodyPart is appended to the list of existing Parts.
      Overrides:
      addBodyPart in class Multipart
      Parameters:
      part - The Part to be appended
      Throws:
      IllegalWriteException - if the underlying implementation does not support modification of existing values
      MessagingException - for other failures
    • addBodyPart

      public void addBodyPart(BodyPart part, int index) throws MessagingException
      Adds a BodyPart at position index. If index is not the last one in the list, the subsequent parts are shifted up. If index is larger than the number of parts present, the BodyPart is appended to the end.
      Overrides:
      addBodyPart in class Multipart
      Parameters:
      part - The BodyPart to be inserted
      index - Location where to insert the part
      Throws:
      IllegalWriteException - if the underlying implementation does not support modification of existing values
      MessagingException - for other failures
    • isComplete

      public boolean isComplete() throws MessagingException
      Return true if the final boundary line for this multipart was seen. When parsing multipart content, this class will (by default) terminate parsing with no error if the end of input is reached before seeing the final multipart boundary line. In such a case, this method will return false. (If the System property "mail.mime.multipart.ignoremissingendboundary" is set to false, parsing such a message will instead throw a MessagingException.)
      Returns:
      true if the final boundary line was seen
      Throws:
      MessagingException - for failures
      Since:
      JavaMail 1.4
    • getPreamble

      public String getPreamble() throws MessagingException
      Get the preamble text, if any, that appears before the first body part of this multipart. Some protocols, such as IMAP, will not allow access to the preamble text.
      Returns:
      the preamble text, or null if no preamble
      Throws:
      MessagingException - for failures
      Since:
      JavaMail 1.4
    • setPreamble

      public void setPreamble(String preamble) throws MessagingException
      Set the preamble text to be included before the first body part. Applications should generally not include any preamble text. In some cases it may be helpful to include preamble text with instructions for users of pre-MIME software. The preamble text should be complete lines, including newlines.
      Parameters:
      preamble - the preamble text
      Throws:
      MessagingException - for failures
      Since:
      JavaMail 1.4
    • updateHeaders

      protected void updateHeaders() throws MessagingException
      Update headers. The default implementation here just calls the updateHeaders method on each of its children BodyParts.

      Note that the boundary parameter is already set up when a new and empty MimeMultipart object is created.

      This method is called when the saveChanges method is invoked on the Message object containing this Multipart. This is typically done as part of the Message send process, however note that a client is free to call it any number of times. So if the header updating process is expensive for a specific MimeMultipart subclass, then it might itself want to track whether its internal state actually did change, and do the header updating only if necessary.

      Throws:
      MessagingException - for failures
    • writeTo

      public void writeTo(OutputStream os) throws IOException, MessagingException
      Iterates through all the parts and outputs each MIME part separated by a boundary.
      Specified by:
      writeTo in class Multipart
      Parameters:
      os - the stream to write to
      Throws:
      IOException - if an IO related exception occurs
      MessagingException - for other failures
    • parse

      protected void parse() throws MessagingException
      Parse the InputStream from our DataSource, constructing the appropriate MimeBodyParts. The parsed flag is set to true, and if true on entry nothing is done. This method is called by all other methods that need data for the body parts, to make sure the data has been parsed. The initializeProperties() method is called before parsing the data.
      Throws:
      ParseException - for failures parsing the message
      MessagingException - for other failures
      Since:
      JavaMail 1.2
    • createInternetHeaders

      protected InternetHeaders createInternetHeaders(InputStream is) throws MessagingException
      Create and return an InternetHeaders object that loads the headers from the given InputStream. Subclasses can override this method to return a subclass of InternetHeaders, if necessary. This implementation simply constructs and returns an InternetHeaders object.
      Parameters:
      is - the InputStream to read the headers from
      Returns:
      an InternetHeaders object
      Throws:
      MessagingException - for failures
      Since:
      JavaMail 1.2
    • createMimeBodyPart

      protected MimeBodyPart createMimeBodyPart(InternetHeaders headers, byte[] content) throws MessagingException
      Create and return a MimeBodyPart object to represent a body part parsed from the InputStream. Subclasses can override this method to return a subclass of MimeBodyPart, if necessary. This implementation simply constructs and returns a MimeBodyPart object.
      Parameters:
      headers - the headers for the body part
      content - the content of the body part
      Returns:
      a MimeBodyPart
      Throws:
      MessagingException - for failures
      Since:
      JavaMail 1.2
    • createMimeBodyPart

      protected MimeBodyPart createMimeBodyPart(InputStream is) throws MessagingException
      Create and return a MimeBodyPart object to represent a body part parsed from the InputStream. Subclasses can override this method to return a subclass of MimeBodyPart, if necessary. This implementation simply constructs and returns a MimeBodyPart object.
      Parameters:
      is - InputStream containing the body part
      Returns:
      a MimeBodyPart
      Throws:
      MessagingException - for failures
      Since:
      JavaMail 1.2