public interface

Part

com.google.code.javax.mail.Part
Known Indirect Subclasses

Class Overview

The Part interface is the common base interface for Messages and BodyParts.

Part consists of a set of attributes and a "Content".

Attributes:

The JavaMail API defines a set of standard Part attributes that are considered to be common to most existing Mail systems. These attributes have their own settor and gettor methods. Mail systems may support other Part attributes as well, these are represented as name-value pairs where both the name and value are Strings.

Content:

The data type of the "content" is returned by the getContentType() method. The MIME typing system is used to name data types.

The "content" of a Part is available in various formats:

  • As a DataHandler - using the getDataHandler() method. The "content" of a Part is also available through a javax.activation.DataHandler object. The DataHandler object allows clients to discover the operations available on the content, and to instantiate the appropriate component to perform those operations.
  • As an input stream - using the getInputStream() method. Any mail-specific encodings are decoded before this stream is returned.
  • As a Java object - using the getContent() method. This method returns the "content" as a Java object. The returned object is of course dependent on the content itself. In particular, a "multipart" Part's content is always a Multipart or subclass thereof. That is, getContent() on a "multipart" type Part will always return a Multipart (or subclass) object.
Part provides the writeTo() method that streams out its bytestream in mail-safe form suitable for transmission. This bytestream is typically an aggregation of the Part attributes and its content's bytestream.

Message and BodyPart implement the Part interface. Note that in MIME parlance, Part models an Entity (RFC 2045, Section 2.4).

Summary

Constants
String ATTACHMENT This part should be presented as an attachment.
String INLINE This part should be presented inline.
Public Methods
abstract void addHeader(String header_name, String header_value)
Add this value to the existing values for this header_name.
abstract Enumeration getAllHeaders()
Return all the headers from this part as an Enumeration of Header objects.
abstract Object getContent()
Return the content as a Java object.
abstract String getContentType()
Returns the Content-Type of the content of this part.
abstract DataHandler getDataHandler()
Return a DataHandler for the content within this part.
abstract String getDescription()
Return a description String for this part.
abstract String getDisposition()
Return the disposition of this part.
abstract String getFileName()
Get the filename associated with this part, if possible.
abstract String[] getHeader(String header_name)
Get all the headers for this header name.
abstract InputStream getInputStream()
Return an input stream for this part's "content".
abstract int getLineCount()
Return the number of lines in the content of this part.
abstract Enumeration getMatchingHeaders(String[] header_names)
Return matching headers from this part as an Enumeration of Header objects.
abstract Enumeration getNonMatchingHeaders(String[] header_names)
Return non-matching headers from this envelope as an Enumeration of Header objects.
abstract int getSize()
Return the size of the content of this part in bytes.
abstract boolean isMimeType(String mimeType)
Is this Part of the specified MIME type? This method compares only the primaryType and subType.
abstract void removeHeader(String header_name)
Remove all headers with this name.
abstract void setContent(Object obj, String type)
A convenience method for setting this part's content.
abstract void setContent(Multipart mp)
This method sets the given Multipart object as this message's content.
abstract void setDataHandler(DataHandler dh)
This method provides the mechanism to set this part's content.
abstract void setDescription(String description)
Set a description String for this part.
abstract void setDisposition(String disposition)
Set the disposition of this part.
abstract void setFileName(String filename)
Set the filename associated with this part, if possible.
abstract void setHeader(String header_name, String header_value)
Set the value for this header_name.
abstract void setText(String text)
A convenience method that sets the given String as this part's content with a MIME type of "text/plain".
abstract void writeTo(OutputStream os)
Output a bytestream for this Part.

Constants

public static final String ATTACHMENT

This part should be presented as an attachment.

Constant Value: "attachment"

public static final String INLINE

This part should be presented inline.

Constant Value: "inline"

Public Methods

public abstract void addHeader (String header_name, String header_value)

Add this value to the existing values for this header_name.

Parameters
header_name The name of this header
header_value The value for this header
Throws
IllegalWriteException if the underlying implementation does not support modification of existing values
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract Enumeration getAllHeaders ()

Return all the headers from this part as an Enumeration of Header objects.

Returns
  • enumeration of Header objects

public abstract Object getContent ()

Return the content as a Java object. The type of the returned object is of course dependent on the content itself. For example, the object returned for "text/plain" content is usually a String object. The object returned for a "multipart" content is always a Multipart subclass. For content-types that are unknown to the DataHandler system, an input stream is returned as the content

This is a convenience method that just invokes the DataHandler's getContent() method

Returns
  • Object
Throws
IOException this is typically thrown by the DataHandler. Refer to the documentation for javax.activation.DataHandler for more details.
MessagingException
See Also

public abstract String getContentType ()

Returns the Content-Type of the content of this part. Returns null if the Content-Type could not be determined.

The MIME typing system is used to name Content-types.

Returns
  • The ContentType of this part
See Also
  • javax.activation.DataHandler

public abstract DataHandler getDataHandler ()

Return a DataHandler for the content within this part. The DataHandler allows clients to operate on as well as retrieve the content.

Returns
  • DataHandler for the content

public abstract String getDescription ()

Return a description String for this part. This typically associates some descriptive information with this part. Returns null if none is available.

Returns
  • description of this part

public abstract String getDisposition ()

Return the disposition of this part. The disposition describes how the part should be presented to the user. (See RFC 2183.) The return value should be considered without regard to case. For example:

 String disp = part.getDisposition();
 if (disp == null || disp.equalsIgnoreCase(Part.ATTACHMENT))
	// treat as attachment if not first part
 

Returns
  • disposition of this part, or null if unknown

public abstract String getFileName ()

Get the filename associated with this part, if possible. Useful if this part represents an "attachment" that was loaded from a file. The filename will usually be a simple name, not including directory components.

Returns
  • Filename to associate with this part

public abstract String[] getHeader (String header_name)

Get all the headers for this header name. Returns null if no headers for this header name are available.

Parameters
header_name The name of this header
Returns
  • the value fields for all headers with this name

public abstract InputStream getInputStream ()

Return an input stream for this part's "content". Any mail-specific transfer encodings will be decoded before the input stream is provided.

This is typically a convenience method that just invokes the DataHandler's getInputStream() method.

Returns
  • an InputStream
Throws
IOException this is typically thrown by the DataHandler. Refer to the documentation for javax.activation.DataHandler for more details.
MessagingException

public abstract int getLineCount ()

Return the number of lines in the content of this part. Return -1 if the 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.

Returns
  • number of lines in the content.

public abstract Enumeration getMatchingHeaders (String[] header_names)

Return matching headers from this part as an Enumeration of Header objects.

Parameters
header_names
Returns
  • enumeration of Header objects

public abstract Enumeration getNonMatchingHeaders (String[] header_names)

Return non-matching headers from this envelope as an Enumeration of Header objects.

Parameters
header_names
Returns
  • enumeration of Header objects

public abstract int getSize ()

Return the size of the content of this part in bytes. Return -1 if the size cannot be determined.

Note that the size may not be an exact measure of the content size and may or may not account for any transfer encoding of the content. The size is appropriate for display in a user interface to give the user a rough idea of the size of this part.

Returns
  • size of content in bytes

public abstract boolean isMimeType (String mimeType)

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.

Parameters
mimeType

public abstract void removeHeader (String header_name)

Remove all headers with this name.

Parameters
header_name The name of this header
Throws
IllegalWriteException if the underlying implementation does not support modification of existing values
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void setContent (Object obj, String type)

A convenience method for setting this part's content. The part internally wraps the content in a DataHandler.

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.

Parameters
obj A java object.
type MIME type of this object.
Throws
IllegalWriteException if the underlying implementation does not support modification of existing values
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void setContent (Multipart mp)

This method sets the given Multipart object as this message's content.

Parameters
mp The multipart object that is the Message's content
Throws
IllegalWriteException if the underlying implementation does not support modification of existing values
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void setDataHandler (DataHandler dh)

This method provides the mechanism to set this part's content. The DataHandler wraps around the actual content.

Parameters
dh The DataHandler for the content.
Throws
IllegalWriteException if the underlying implementation does not support modification of existing values
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void setDescription (String description)

Set a description String for this part. This typically associates some descriptive information with this part.

Parameters
description Description of this part
Throws
IllegalWriteException if the underlying implementation does not support modification of this header
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void setDisposition (String disposition)

Set the disposition of this part.

Parameters
disposition Disposition of this part
Throws
IllegalWriteException if the underlying implementation does not support modification of this header
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void setFileName (String filename)

Set the filename associated with this part, if possible. Useful if this part represents an "attachment" that was loaded from a file. The filename will usually be a simple name, not including directory components.

Parameters
filename Filename to associate with this part
Throws
IllegalWriteException if the underlying implementation does not support modification of this header
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void setHeader (String header_name, String header_value)

Set the value for this header_name. Replaces all existing header values with this new value.

Parameters
header_name The name of this header
header_value The value for this header
Throws
IllegalWriteException if the underlying implementation does not support modification of existing values
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void setText (String text)

A convenience method that sets the given String as this part's content with a MIME type of "text/plain".

Parameters
text The text that is the Message's content.
Throws
IllegalWriteException if the underlying implementation does not support modification of existing values
IllegalStateException if this Part is obtained from a READ_ONLY folder
MessagingException

public abstract void writeTo (OutputStream os)

Output a bytestream for this Part. This bytestream is typically an aggregration of the Part attributes and an appropriately encoded bytestream from its 'content'.

Classes that implement the Part interface decide on the appropriate encoding algorithm to be used.

The bytestream is typically used for sending.

Parameters
os
Throws
IOException if an error occurs writing to the stream or if an error is generated by the javax.activation layer.
MessagingException if an error occurs fetching the data to be written