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javax.mail.internet
public class: MimeMessage [javadoc | source]
java.lang.Object
   javax.mail.Message
      javax.mail.internet.MimeMessage

All Implemented Interfaces:
    MimePart, Part

This class represents a MIME style email message. It implements the Message abstract class and the MimePart interface.

Clients wanting to create new MIME style messages will instantiate an empty MimeMessage object and then fill it with appropriate attributes and content.

Service providers that implement MIME compliant backend stores may want to subclass MimeMessage and override certain methods to provide specific implementations. The simplest case is probably a provider that generates a MIME style input stream and leaves the parsing of the stream to this class.

MimeMessage uses the InternetHeaders class to parse and store the top level RFC 822 headers of a message.

The mail.mime.address.strict session property controls the parsing of address headers. By default, strict parsing of address headers is done. If this property is set to "false", strict parsing is not done and many illegal addresses that sometimes occur in real messages are allowed. See the InternetAddress class for details.


A note on RFC 822 and MIME headers

RFC 822 header fields must contain only US-ASCII characters. MIME allows non ASCII characters to be present in certain portions of certain headers, by encoding those characters. RFC 2047 specifies the rules for doing this. The MimeUtility class provided in this package can be used to to achieve this. Callers of the setHeader, addHeader, and addHeaderLine methods are responsible for enforcing the MIME requirements for the specified headers. In addition, these header fields must be folded (wrapped) before being sent if they exceed the line length limitation for the transport (1000 bytes for SMTP). Received headers may have been folded. The application is responsible for folding and unfolding headers as appropriate.

Nested Class Summary:
public static class  MimeMessage.RecipientType  This inner class extends the javax.mail.Message.RecipientType class to add additional RecipientTypes. The one additional RecipientType currently defined here is NEWSGROUPS. 
Field Summary
protected  DataHandler dh    The DataHandler object representing this Message's content. 
protected  byte[] content    Byte array that holds the bytes of this Message's content. 
protected  InputStream contentStream    If the data for this message was supplied by an InputStream that implements the SharedInputStream interface, contentStream is another such stream representing the content of this message. In this case, content will be null.
    since: JavaMail - 1.2
 
protected  InternetHeaders headers    The InternetHeaders object that stores the header of this message. 
protected  Flags flags    The Flags for this message. 
protected  boolean modified    A flag indicating whether the message has been modified. If the message has not been modified, any data in the content array is assumed to be valid and is used directly in the writeTo method. This flag is set to true when an empty message is created or when the saveChanges method is called.
    since: JavaMail - 1.2
 
protected  boolean saved    Does the saveChanges method need to be called on this message? This flag is set to false by the public constructor and set to true by the saveChanges method. The writeTo method checks this flag and calls the saveChanges method as necessary. This avoids the common mistake of forgetting to call the saveChanges method on a newly constructed message.
    since: JavaMail - 1.2
 
 Object cachedContent    If our content is a Multipart of Message object, we save it the first time it's created by parsing a stream so that changes to the contained objects will not be lost. XXX - must have package access for MimeBodyPart.updateHeaders 
Fields inherited from javax.mail.Message:
msgnum,  expunged,  folder,  session
Constructor:
 public MimeMessage(Session session) 
    Default constructor. An empty message object is created. The headers field is set to an empty InternetHeaders object. The flags field is set to an empty Flags object. The modified flag is set to true.
 public MimeMessage(MimeMessage source) throws MessagingException 
    Constructs a new MimeMessage with content initialized from the source MimeMessage. The new message is independent of the original.

    Note: The current implementation is rather inefficient, copying the data more times than strictly necessary.

    Parameters:
    source - the message to copy content from
    Throws:
    MessagingException -
    exception: MessagingException -
    since: JavaMail - 1.2
 public MimeMessage(Session session,
    InputStream is) throws MessagingException 
    Constructs a MimeMessage by reading and parsing the data from the specified MIME InputStream. The InputStream will be left positioned at the end of the data for the message. Note that the input stream parse is done within this constructor itself.

    The input stream contains an entire MIME formatted message with headers and data.

    Parameters:
    session - Session object for this message
    is - the message input stream
    Throws:
    MessagingException -
    exception: MessagingException -
 protected MimeMessage(Folder folder,
    int msgnum) 
    Constructs an empty MimeMessage object with the given Folder and message number.

    This method is for providers subclassing MimeMessage.

 protected MimeMessage(Folder folder,
    InputStream is,
    int msgnum) throws MessagingException 
    Constructs a MimeMessage by reading and parsing the data from the specified MIME InputStream. The InputStream will be left positioned at the end of the data for the message. Note that the input stream parse is done within this constructor itself.

    This method is for providers subclassing MimeMessage.

    Parameters:
    folder - The containing folder.
    is - the message input stream
    msgnum - Message number of this message within its folder
    Throws:
    MessagingException -
    exception: MessagingException -
 protected MimeMessage(Folder folder,
    InternetHeaders headers,
    byte[] content,
    int msgnum) throws MessagingException 
    Constructs a MimeMessage from the given InternetHeaders object and content. This method is for providers subclassing MimeMessage.
    Parameters:
    folder - The containing folder.
    headers - The headers
    content - The message content
    msgnum - Message number of this message within its folder
    Throws:
    MessagingException -
    exception: MessagingException -
Method from javax.mail.internet.MimeMessage Summary:
addFrom,   addHeader,   addHeaderLine,   addRecipients,   addRecipients,   createInternetHeaders,   createMimeMessage,   getAllHeaderLines,   getAllHeaders,   getAllRecipients,   getContent,   getContentID,   getContentLanguage,   getContentMD5,   getContentStream,   getContentType,   getDataHandler,   getDescription,   getDisposition,   getEncoding,   getFileName,   getFlags,   getFrom,   getHeader,   getHeader,   getInputStream,   getLineCount,   getMatchingHeaderLines,   getMatchingHeaders,   getMessageID,   getNonMatchingHeaderLines,   getNonMatchingHeaders,   getRawInputStream,   getReceivedDate,   getRecipients,   getReplyTo,   getSender,   getSentDate,   getSize,   getSubject,   isMimeType,   isSet,   parse,   removeHeader,   reply,   saveChanges,   setContent,   setContent,   setContentID,   setContentLanguage,   setContentMD5,   setDataHandler,   setDescription,   setDescription,   setDisposition,   setFileName,   setFlags,   setFrom,   setFrom,   setHeader,   setRecipients,   setRecipients,   setReplyTo,   setSender,   setSentDate,   setSubject,   setSubject,   setText,   setText,   setText,   updateHeaders,   updateMessageID,   writeTo,   writeTo
Methods from javax.mail.Message:
addFrom,   addRecipient,   addRecipients,   getAllRecipients,   getFlags,   getFolder,   getFrom,   getMessageNumber,   getReceivedDate,   getRecipients,   getReplyTo,   getSentDate,   getSubject,   isExpunged,   isSet,   match,   reply,   saveChanges,   setExpunged,   setFlag,   setFlags,   setFrom,   setFrom,   setMessageNumber,   setRecipient,   setRecipients,   setReplyTo,   setSentDate,   setSubject
Methods from java.lang.Object:
equals,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from javax.mail.internet.MimeMessage Detail:
 public  void addFrom(Address[] addresses) throws MessagingException 
    Add the specified addresses to the existing "From" field. If the "From" field does not already exist, it is created.
 public  void addHeader(String name,
    String value) throws MessagingException 
    Add this value to the existing values for this header_name. Note that RFC 822 headers must contain only US-ASCII characters, so a header that contains non US-ASCII characters must have been encoded as per the rules of RFC 2047.
 public  void addHeaderLine(String line) throws MessagingException 
    Add a raw RFC 822 header-line.
 public  void addRecipients(Message.RecipientType type,
    Address[] addresses) throws MessagingException 
    Add the given addresses to the specified recipient type.
 public  void addRecipients(Message.RecipientType type,
    String addresses) throws MessagingException 
    Add the given addresses to the specified recipient type.
 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.
 protected MimeMessage createMimeMessage(Session session) throws MessagingException 
    Create and return a MimeMessage object. The reply method uses this method to create the MimeMessage object that it will return. Subclasses can override this method to return a subclass of MimeMessage. This implementation simply constructs and returns a MimeMessage object using the supplied Session.
 public Enumeration getAllHeaderLines() throws MessagingException 
    Get all header lines as an Enumeration of Strings. A Header line is a raw RFC 822 header-line, containing both the "name" and "value" field.
 public Enumeration getAllHeaders() throws MessagingException 
    Return all the headers from this Message as an enumeration of Header objects.

    Note that certain headers may be encoded as per RFC 2047 if they contain non US-ASCII characters and these should be decoded.

    This implementation obtains the headers from the headers InternetHeaders object.

 public Address[] getAllRecipients() throws MessagingException 
    Get all the recipient addresses for the message. Extracts the TO, CC, BCC, and NEWSGROUPS recipients.
 public Object getContent() throws IOException, MessagingException 
    Return the content as a Java object. The type of this object is dependent on the content itself. For example, the native format of a "text/plain" content is usually a String object. The native format for a "multipart" message is always a Multipart subclass. For content types that are unknown to the DataHandler system, an input stream is returned as the content.

    This implementation obtains the content from the DataHandler, that is, it invokes getDataHandler().getContent(). If the content is a Multipart or Message object and was created by parsing a stream, the object is cached and returned in subsequent calls so that modifications to the content will not be lost.

 public String getContentID() throws MessagingException 
    Returns the value of the "Content-ID" header field. Returns null if the field is unavailable or its value is absent.

    This implementation uses the getHeader method to obtain the requisite header field.

 public String[] getContentLanguage() throws MessagingException 
    Get the languages specified in the "Content-Language" header field of this message. The Content-Language header is defined by RFC 1766. Returns null if this field is unavailable or its value is absent.

    This implementation uses the getHeader method to obtain the requisite header field.

 public String getContentMD5() throws MessagingException 
    Return the value of the "Content-MD5" header field. Returns null if this field is unavailable or its value is absent.

    This implementation uses the getHeader method to obtain the requisite header field.

 protected InputStream getContentStream() throws MessagingException 
    Produce the raw bytes of the content. This method is used during parsing, to create a DataHandler object for the content. Subclasses that can provide a separate input stream for just the message content might want to override this method.

    This implementation returns a SharedInputStream, if contentStream is not null. Otherwise, it returns a ByteArrayInputStream constructed out of the content byte array.

 public String getContentType() throws MessagingException 
    Returns the value of the RFC 822 "Content-Type" header field. This represents the content-type of the content of this message. This value must not be null. If this field is unavailable, "text/plain" should be returned.

    This implementation uses the getHeader method to obtain the requisite header field.

 public synchronized DataHandler getDataHandler() throws MessagingException 
    Return a DataHandler for this Message's content.

    The implementation provided here works as follows. Note the use of the getContentStream method to generate the byte stream for the content. Also note that any transfer-decoding is done automatically within this method.

    getDataHandler() {
    if (dh == null) {
    dh = new DataHandler(new MimePartDataSource(this));
    }
    return dh;
    }
    

    class MimePartDataSource implements DataSource { public getInputStream() { return MimeUtility.decode( getContentStream(), getEncoding()); } .... }

 public String getDescription() throws MessagingException 
    Returns the "Content-Description" header field of this Message. This typically associates some descriptive information with this part. Returns null if this field is unavailable or its value is absent.

    If the Content-Description field is encoded as per RFC 2047, it is decoded and converted into Unicode. If the decoding or conversion fails, the raw data is returned as-is

    This implementation uses the getHeader method to obtain the requisite header field.

 public String getDisposition() throws MessagingException 
    Returns the value of the "Content-Disposition" header field. This represents the disposition of this part. The disposition describes how the part should be presented to the user.

    If the Content-Disposition field is unavailable, null is returned.

    This implementation uses the getHeader method to obtain the requisite header field.

 public String getEncoding() throws MessagingException 
    Returns the content transfer encoding from the "Content-Transfer-Encoding" header field. Returns null if the header is unavailable or its value is absent.

    This implementation uses the getHeader method to obtain the requisite header field.

 public String getFileName() throws MessagingException 
    Get the filename associated with this Message.

    Returns the value of the "filename" parameter from the "Content-Disposition" header field of this message. If it's not available, returns the value of the "name" parameter from the "Content-Type" header field of this BodyPart. Returns null if both are absent.

    If the mail.mime.encodefilename System property is set to true, the MimeUtility.decodeText method will be used to decode the filename. While such encoding is not supported by the MIME spec, many mailers use this technique to support non-ASCII characters in filenames. The default value of this property is false.

 public synchronized Flags getFlags() throws MessagingException 
    Return a Flags object containing the flags for this message.

    Note that a clone of the internal Flags object is returned, so modifying the returned Flags object will not affect the flags of this message.

 public Address[] getFrom() throws MessagingException 
    Returns the value of the RFC 822 "From" header fields. If this header field is absent, the "Sender" header field is used. If the "Sender" header field is also absent, null is returned.

    This implementation uses the getHeader method to obtain the requisite header field.

 public String[] getHeader(String name) throws MessagingException 
    Get all the headers for this header_name. Note that certain headers may be encoded as per RFC 2047 if they contain non US-ASCII characters and these should be decoded.

    This implementation obtains the headers from the headers InternetHeaders object.

 public String getHeader(String name,
    String delimiter) throws MessagingException 
    Get all the headers for this header name, returned as a single String, with headers separated by the delimiter. If the delimiter is null, only the first header is returned.
 public InputStream getInputStream() throws IOException, MessagingException 
    Return a decoded input stream for this Message's "content".

    This implementation obtains the input stream from the DataHandler, that is, it invokes getDataHandler().getInputStream().

 public int getLineCount() throws MessagingException 
    Return the number of lines for the content of this message. Return -1 if this number cannot be determined.

    Note that this number may not be an exact measure of the content length and may or may not account for any transfer encoding of the content.

    This implementation returns -1.

 public Enumeration getMatchingHeaderLines(String[] names) throws MessagingException 
    Get matching header lines as an Enumeration of Strings. A Header line is a raw RFC 822 header-line, containing both the "name" and "value" field.
 public Enumeration getMatchingHeaders(String[] names) throws MessagingException 
    Return matching headers from this Message as an Enumeration of Header objects. This implementation obtains the headers from the headers InternetHeaders object.
 public String getMessageID() throws MessagingException 
    Returns the value of the "Message-ID" header field. Returns null if this field is unavailable or its value is absent.

    The default implementation provided here uses the getHeader method to return the value of the "Message-ID" field.

 public Enumeration getNonMatchingHeaderLines(String[] names) throws MessagingException 
    Get non-matching header lines as an Enumeration of Strings. A Header line is a raw RFC 822 header-line, containing both the "name" and "value" field.
 public Enumeration getNonMatchingHeaders(String[] names) throws MessagingException 
    Return non-matching headers from this Message as an Enumeration of Header objects. This implementation obtains the header from the headers InternetHeaders object.
 public InputStream getRawInputStream() throws MessagingException 
    Return an InputStream to the raw data with any Content-Transfer-Encoding intact. This method is useful if the "Content-Transfer-Encoding" header is incorrect or corrupt, which would prevent the getInputStream method or getContent method from returning the correct data. In such a case the application may use this method and attempt to decode the raw data itself.

    This implementation simply calls the getContentStream method.

 public Date getReceivedDate() throws MessagingException 
    Returns the Date on this message was received. Returns null if this date cannot be obtained.

    Note that RFC 822 does not define a field for the received date. Hence only implementations that can provide this date need return a valid value.

    This implementation returns null.

 public Address[] getRecipients(Message.RecipientType type) throws MessagingException 
    Returns the recepients specified by the type. The mapping between the type and the corresponding RFC 822 header is as follows:
    Message.RecipientType.TO "To"
    Message.RecipientType.CC "Cc"
    Message.RecipientType.BCC "Bcc"
    MimeMessage.RecipientType.NEWSGROUPS "Newsgroups"
    

    Returns null if the header specified by the type is not found or if its value is empty.

    This implementation uses the getHeader method to obtain the requisite header field.

 public Address[] getReplyTo() throws MessagingException 
    Return the value of the RFC 822 "Reply-To" header field. If this header is unavailable or its value is absent, then the getFrom method is called and its value is returned. This implementation uses the getHeader method to obtain the requisite header field.
 public Address getSender() throws MessagingException 
    Returns the value of the RFC 822 "Sender" header field. If the "Sender" header field is absent, null is returned.

    This implementation uses the getHeader method to obtain the requisite header field.

 public Date getSentDate() throws MessagingException 
    Returns the value of the RFC 822 "Date" field. This is the date on which this message was sent. Returns null if this field is unavailable or its value is absent.

    This implementation uses the getHeader method to obtain the requisite header field.

 public int getSize() throws MessagingException 
    Return the size of the content of this message in bytes. Return -1 if the size cannot be determined.

    Note that this number may not be an exact measure of the content size and may or may not account for any transfer encoding of the content.

    This implementation returns the size of the content array (if not null), or, if contentStream is not null, and the available method returns a positive number, it returns that number as the size. Otherwise, it returns -1.

 public String getSubject() throws MessagingException 
    Returns the value of the "Subject" header field. Returns null if the subject field is unavailable or its value is absent.

    If the subject is encoded as per RFC 2047, it is decoded and converted into Unicode. If the decoding or conversion fails, the raw data is returned as is.

    This implementation uses the getHeader method to obtain the requisite header field.

 public boolean isMimeType(String mimeType) throws MessagingException 
    Is this Part of the specified MIME type? This method compares only the primaryType and subType. The parameters of the content types are ignored.

    For example, this method will return true when comparing a Part of content type "text/plain" with "text/plain; charset=foobar".

    If the subType of mimeType is the special character '*', then the subtype is ignored during the comparison.

 public synchronized boolean isSet(Flags.Flag flag) throws MessagingException 
    Check whether the flag specified in the flag argument is set in this message.

    This implementation checks this message's internal flags object.

 protected  void parse(InputStream is) throws MessagingException 
    Parse the InputStream setting the headers and content fields appropriately. Also resets the modified flag.

    This method is intended for use by subclasses that need to control when the InputStream is parsed.

 public  void removeHeader(String name) throws MessagingException 
    Remove all headers with this name.
 public Message reply(boolean replyToAll) throws MessagingException 
    Get a new Message suitable for a reply to this message. The new Message will have its attributes and headers set up appropriately. Note that this new message object will be empty, i.e., it will not have a "content". These will have to be suitably filled in by the client.

    If replyToAll is set, the new Message will be addressed to all recipients of this message. Otherwise, the reply will be addressed to only the sender of this message (using the value of the getReplyTo method).

    The "Subject" field is filled in with the original subject prefixed with "Re:" (unless it already starts with "Re:"). The "In-Reply-To" header is set in the new message if this message has a "Message-Id" header. The ANSWERED flag is set in this message. The current implementation also sets the "References" header in the new message to include the contents of the "References" header (or, if missing, the "In-Reply-To" header) in this message, plus the contents of the "Message-Id" header of this message, as described in RFC 2822.

 public  void saveChanges() throws MessagingException 
    Updates the appropriate header fields of this message to be consistent with the message's contents. If this message is contained in a Folder, any changes made to this message are committed to the containing folder.

    If any part of a message's headers or contents are changed, saveChanges must be called to ensure that those changes are permanent. Otherwise, any such modifications may or may not be saved, depending on the folder implementation.

    Messages obtained from folders opened READ_ONLY should not be modified and saveChanges should not be called on such messages.

    This method sets the modified flag to true, the save flag to true, and then calls the updateHeaders method.

 public  void setContent(Multipart mp) throws MessagingException 
    This method sets the Message's content to a Multipart object.
 public  void setContent(Object o,
    String type) throws MessagingException 
    A convenience method for setting this Message's content.

    The content is wrapped in a DataHandler object. Note that a DataContentHandler class for the specified type should be available to the JavaMail implementation for this to work right. i.e., to do setContent(foobar, "application/x-foobar"), a DataContentHandler for "application/x-foobar" should be installed. Refer to the Java Activation Framework for more information.

 public  void setContentID(String cid) throws MessagingException 
    Set the "Content-ID" header field of this Message. If the cid parameter is null, any existing "Content-ID" is removed.
 public  void setContentLanguage(String[] languages) throws MessagingException 
    Set the "Content-Language" header of this MimePart. The Content-Language header is defined by RFC 1766.
 public  void setContentMD5(String md5) throws MessagingException 
    Set the "Content-MD5" header field of this Message.
 public synchronized  void setDataHandler(DataHandler dh) throws MessagingException 
    This method provides the mechanism to set this part's content. The given DataHandler object should wrap the actual content.
 public  void setDescription(String description) throws MessagingException 
    Set the "Content-Description" header field for this Message. If the description parameter is null, then any existing "Content-Description" fields are removed.

    If the description contains non US-ASCII characters, it will be encoded using the platform's default charset. If the description contains only US-ASCII characters, no encoding is done and it is used as-is.

    Note that if the charset encoding process fails, a MessagingException is thrown, and an UnsupportedEncodingException is included in the chain of nested exceptions within the MessagingException.

 public  void setDescription(String description,
    String charset) throws MessagingException 
    Set the "Content-Description" header field for this Message. If the description parameter is null, then any existing "Content-Description" fields are removed.

    If the description contains non US-ASCII characters, it will be encoded using the specified charset. If the description contains only US-ASCII characters, no encoding is done and it is used as-is.

    Note that if the charset encoding process fails, a MessagingException is thrown, and an UnsupportedEncodingException is included in the chain of nested exceptions within the MessagingException.

 public  void setDisposition(String disposition) throws MessagingException 
    Set the "Content-Disposition" header field of this Message. If disposition is null, any existing "Content-Disposition" header field is removed.
 public  void setFileName(String filename) throws MessagingException 
    Set the filename associated with this part, if possible.

    Sets the "filename" parameter of the "Content-Disposition" header field of this message.

    If the mail.mime.encodefilename System property is set to true, the MimeUtility.encodeText method will be used to encode the filename. While such encoding is not supported by the MIME spec, many mailers use this technique to support non-ASCII characters in filenames. The default value of this property is false.

 public synchronized  void setFlags(Flags flag,
    boolean set) throws MessagingException 
    Set the flags for this message.

    This implementation modifies the flags field.

 public  void setFrom() throws MessagingException 
    Set the RFC 822 "From" header field using the value of the InternetAddress.getLocalAddress method.
 public  void setFrom(Address address) throws MessagingException 
    Set the RFC 822 "From" header field. Any existing values are replaced with the given address. If address is null, this header is removed.
 public  void setHeader(String name,
    String value) throws MessagingException 
    Set the value for this header_name. Replaces all existing header values with this new value. Note that RFC 822 headers must contain only US-ASCII characters, so a header that contains non US-ASCII characters must have been encoded by the caller as per the rules of RFC 2047.
 public  void setRecipients(Message.RecipientType type,
    Address[] addresses) throws MessagingException 
    Set the specified recipient type to the given addresses. If the address parameter is null, the corresponding recipient field is removed.
 public  void setRecipients(Message.RecipientType type,
    String addresses) throws MessagingException 
    Set the specified recipient type to the given addresses. If the address parameter is null, the corresponding recipient field is removed.
 public  void setReplyTo(Address[] addresses) throws MessagingException 
    Set the RFC 822 "Reply-To" header field. If the address parameter is null, this header is removed.
 public  void setSender(Address address) throws MessagingException 
    Set the RFC 822 "Sender" header field. Any existing values are replaced with the given address. If address is null, this header is removed.
 public  void setSentDate(Date d) throws MessagingException 
    Set the RFC 822 "Date" header field. This is the date on which the creator of the message indicates that the message is complete and ready for delivery. If the date parameter is null, the existing "Date" field is removed.
 public  void setSubject(String subject) throws MessagingException 
    Set the "Subject" header field. If the subject contains non US-ASCII characters, it will be encoded using the platform's default charset. If the subject contains only US-ASCII characters, no encoding is done and it is used as-is. If the subject is null, the existing "Subject" field is removed.

    The application must ensure that the subject does not contain any line breaks.

    Note that if the charset encoding process fails, a MessagingException is thrown, and an UnsupportedEncodingException is included in the chain of nested exceptions within the MessagingException.

 public  void setSubject(String subject,
    String charset) throws MessagingException 
    Set the "Subject" header field. If the subject contains non US-ASCII characters, it will be encoded using the specified charset. If the subject contains only US-ASCII characters, no encoding is done and it is used as-is. If the subject is null, the existing "Subject" header field is removed.

    The application must ensure that the subject does not contain any line breaks.

    Note that if the charset encoding process fails, a MessagingException is thrown, and an UnsupportedEncodingException is included in the chain of nested exceptions within the MessagingException.

 public  void setText(String text) throws MessagingException 
    Convenience method that sets the given String as this part's content, with a MIME type of "text/plain". If the string contains non US-ASCII characters. it will be encoded using the platform's default charset. The charset is also used to set the "charset" parameter.

    Note that there may be a performance penalty if text is large, since this method may have to scan all the characters to determine what charset to use.

    If the charset is already known, use the setText method that takes the charset parameter.

 public  void setText(String text,
    String charset) throws MessagingException 
    Convenience method that sets the given String as this part's content, with a MIME type of "text/plain" and the specified charset. The given Unicode string will be charset-encoded using the specified charset. The charset is also used to set the "charset" parameter.
 public  void setText(String text,
    String charset,
    String subtype) throws MessagingException 
    Convenience method that sets the given String as this part's content, with a primary MIME type of "text" and the specified MIME subtype. The given Unicode string will be charset-encoded using the specified charset. The charset is also used to set the "charset" parameter.
 protected  void updateHeaders() throws MessagingException 
    Called by the saveChanges method to actually update the MIME headers. The implementation here sets the Content-Transfer-Encoding header (if needed and not already set), the MIME-Version header and the Message-ID header. Also, if the content of this message is a MimeMultipart, it's updateHeaders method is called.
 protected  void updateMessageID() throws MessagingException 
    Update the Message-ID header. This method is called by the updateHeaders and allows a subclass to override only the algorithm for choosing a Message-ID.
 public  void writeTo(OutputStream os) throws IOException, MessagingException 
    Output the message as an RFC 822 format stream.

    Note that, depending on how the messag was constructed, it may use a variety of line termination conventions. Generally the output should be sent through an appropriate FilterOutputStream that converts the line terminators to the desired form, either CRLF for MIME compatibility and for use in Internet protocols, or the local platform's line terminator for storage in a local text file.

    This implementation calls the writeTo(OutputStream, String[]) method with a null ignore list.

 public  void writeTo(OutputStream os,
    String[] ignoreList) throws IOException, MessagingException 
    Output the message as an RFC 822 format stream, without specified headers. If the saved flag is not set, the saveChanges method is called. If the modified flag is not set and the content array is not null, the content array is written directly, after writing the appropriate message headers.