jakarta.mail.internet.MimeMultipart Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2021 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package jakarta.mail.internet;
import java.io.BufferedInputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.EOFException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import jakarta.activation.DataSource;
import jakarta.mail.BodyPart;
import jakarta.mail.IllegalWriteException;
import jakarta.mail.MessageAware;
import jakarta.mail.MessageContext;
import jakarta.mail.MessagingException;
import jakarta.mail.Multipart;
import jakarta.mail.MultipartDataSource;
import jakarta.mail.util.LineInputStream;
import jakarta.mail.util.LineOutputStream;
/**
* 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.
*
* @author John Mani
* @author Bill Shannon
* @author Max Spivak
*/
public class MimeMultipart extends Multipart {
/**
* The DataSource supplying our InputStream.
*/
protected DataSource ds = null;
/**
* 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.
*/
protected boolean parsed = true;
/**
* Have we seen the final bounary line?
*
* @since JavaMail 1.5
*/
protected boolean complete = true;
/**
* The MIME multipart preamble text, the text that
* occurs before the first boundary line.
*
* @since JavaMail 1.5
*/
protected String preamble = null;
/**
* Flag corresponding to the "mail.mime.multipart.ignoremissingendboundary"
* property, set in the {@link #initializeProperties} method called from
* constructors and the parse method.
*
* @since JavaMail 1.5
*/
protected boolean ignoreMissingEndBoundary = true;
/**
* Flag corresponding to the
* "mail.mime.multipart.ignoremissingboundaryparameter"
* property, set in the {@link #initializeProperties} method called from
* constructors and the parse method.
*
* @since JavaMail 1.5
*/
protected boolean ignoreMissingBoundaryParameter = true;
/**
* Flag corresponding to the
* "mail.mime.multipart.ignoreexistingboundaryparameter"
* property, set in the {@link #initializeProperties} method called from
* constructors and the parse method.
*
* @since JavaMail 1.5
*/
protected boolean ignoreExistingBoundaryParameter = false;
/**
* Flag corresponding to the "mail.mime.multipart.allowempty"
* property, set in the {@link #initializeProperties} method called from
* constructors and the parse method.
*
* @since JavaMail 1.5
*/
protected boolean allowEmpty = false;
/**
* 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.
*/
public MimeMultipart() {
this("mixed");
}
/**
* 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 {@link #initializeProperties} method.
*
* MimeBodyParts may be added later.
*
* @param subtype the MIME content subtype
*/
public MimeMultipart(String subtype) {
super();
/*
* Compute a boundary string.
*/
String boundary = UniqueValue.getUniqueBoundaryValue();
ContentType cType = new ContentType("multipart", subtype, null);
cType.setParameter("boundary", boundary);
contentType = cType.toString();
initializeProperties();
}
/**
* Construct a MimeMultipart object of the default "mixed" subtype,
* and with the given body parts. More body parts may be added later.
*
* @param parts the body parts
* @exception MessagingException for failures
* @since JavaMail 1.5
*/
public MimeMultipart(BodyPart... parts) throws MessagingException {
this();
for (BodyPart bp : parts)
super.addBodyPart(bp);
}
/**
* Construct a MimeMultipart object of the given subtype
* and with the given body parts. More body parts may be added later.
*
* @param subtype the MIME content subtype
* @param parts the body parts
* @exception MessagingException for failures
* @since JavaMail 1.5
*/
public MimeMultipart(String subtype, BodyPart... parts)
throws MessagingException {
this(subtype);
for (BodyPart bp : parts)
super.addBodyPart(bp);
}
/**
* 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.
*
* @param ds DataSource, can be a MultipartDataSource
* @exception ParseException for failures parsing the message
* @exception MessagingException for other failures
*/
public MimeMultipart(DataSource ds) throws MessagingException {
super();
if (ds instanceof MessageAware) {
MessageContext mc = ((MessageAware)ds).getMessageContext();
setParent(mc.getPart());
}
if (ds instanceof MultipartDataSource) {
// ask super to do this for us.
setMultipartDataSource((MultipartDataSource)ds);
return;
}
// 'ds' was not a MultipartDataSource, we have
// to parse this ourself.
parsed = false;
this.ds = ds;
contentType = ds.getContentType();
}
/**
* Initialize flags that control parsing behavior,
* based on System properties described above in
* the class documentation.
*
* @since JavaMail 1.5
*/
protected void initializeProperties() {
// read properties that control parsing
// default to true
ignoreMissingEndBoundary = MimeUtility.getBooleanSystemProperty(
"mail.mime.multipart.ignoremissingendboundary", true);
// default to true
ignoreMissingBoundaryParameter = MimeUtility.getBooleanSystemProperty(
"mail.mime.multipart.ignoremissingboundaryparameter", true);
// default to false
ignoreExistingBoundaryParameter = MimeUtility.getBooleanSystemProperty(
"mail.mime.multipart.ignoreexistingboundaryparameter", false);
// default to false
allowEmpty = MimeUtility.getBooleanSystemProperty(
"mail.mime.multipart.allowempty", false);
}
/**
* 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".
*
* @param subtype Subtype
* @exception MessagingException for failures
*/
public synchronized void setSubType(String subtype)
throws MessagingException {
ContentType cType = new ContentType(contentType);
cType.setSubType(subtype);
contentType = cType.toString();
}
/**
* Return the number of enclosed BodyPart objects.
*
* @return number of parts
*/
@Override
public synchronized int getCount() throws MessagingException {
parse();
return super.getCount();
}
/**
* Get the specified BodyPart. BodyParts are numbered starting at 0.
*
* @param index the index of the desired BodyPart
* @return the Part
* @exception MessagingException if no such BodyPart exists
*/
@Override
public synchronized BodyPart getBodyPart(int index)
throws MessagingException {
parse();
return super.getBodyPart(index);
}
/**
* Get the MimeBodyPart referred to by the given ContentID (CID).
* Returns null if the part is not found.
*
* @param CID the ContentID of the desired part
* @return the Part
* @exception MessagingException for failures
*/
public synchronized BodyPart getBodyPart(String CID)
throws MessagingException {
parse();
int count = getCount();
for (int i = 0; i < count; i++) {
MimeBodyPart part = (MimeBodyPart)getBodyPart(i);
String s = part.getContentID();
if (s != null && s.equals(CID))
return part;
}
return null;
}
/**
* Remove the specified part from the multipart message.
* Shifts all the parts after the removed part down one.
*
* @param part The part to remove
* @return true if part removed, false otherwise
* @exception MessagingException if no such Part exists
* @exception IllegalWriteException if the underlying
* implementation does not support modification
* of existing values
*/
@Override
public boolean removeBodyPart(BodyPart part) throws MessagingException {
parse();
return super.removeBodyPart(part);
}
/**
* Remove the part at specified location (starting from 0).
* Shifts all the parts after the removed part down one.
*
* @param index Index of the part to remove
* @exception IndexOutOfBoundsException if the given index
* is out of range.
* @exception IllegalWriteException if the underlying
* implementation does not support modification
* of existing values
* @exception MessagingException for other failures
*/
@Override
public void removeBodyPart(int index) throws MessagingException {
parse();
super.removeBodyPart(index);
}
/**
* Adds a Part to the multipart. The BodyPart is appended to
* the list of existing Parts.
*
* @param part The Part to be appended
* @exception IllegalWriteException if the underlying
* implementation does not support modification
* of existing values
* @exception MessagingException for other failures
*/
@Override
public synchronized void addBodyPart(BodyPart part)
throws MessagingException {
parse();
super.addBodyPart(part);
}
/**
* 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.
*
* @param part The BodyPart to be inserted
* @param index Location where to insert the part
* @exception IllegalWriteException if the underlying
* implementation does not support modification
* of existing values
* @exception MessagingException for other failures
*/
@Override
public synchronized void addBodyPart(BodyPart part, int index)
throws MessagingException {
parse();
super.addBodyPart(part, index);
}
/**
* 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.)
*
* @return true if the final boundary line was seen
* @exception MessagingException for failures
* @since JavaMail 1.4
*/
public synchronized boolean isComplete() throws MessagingException {
parse();
return complete;
}
/**
* 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.
*
* @return the preamble text, or null if no preamble
* @exception MessagingException for failures
* @since JavaMail 1.4
*/
public synchronized String getPreamble() throws MessagingException {
parse();
return preamble;
}
/**
* 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.
*
* @param preamble the preamble text
* @exception MessagingException for failures
* @since JavaMail 1.4
*/
public synchronized void setPreamble(String preamble)
throws MessagingException {
this.preamble = preamble;
}
/**
* 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.
*
* @exception MessagingException for failures
*/
protected synchronized void updateHeaders() throws MessagingException {
parse();
for (int i = 0; i < parts.size(); i++)
((MimeBodyPart)parts.elementAt(i)).updateHeaders();
}
/**
* Iterates through all the parts and outputs each MIME part
* separated by a boundary.
*/
@Override
public synchronized void writeTo(OutputStream os)
throws IOException, MessagingException {
parse();
String boundary = "--" +
(new ContentType(contentType)).getParameter("boundary");
LineOutputStream los = streamProvider.outputLineStream(os, false);
// if there's a preamble, write it out
if (preamble != null) {
byte[] pb = MimeUtility.getBytes(preamble);
los.write(pb);
// make sure it ends with a newline
if (pb.length > 0 &&
!(pb[pb.length-1] == '\r' || pb[pb.length-1] == '\n')) {
los.writeln();
}
// XXX - could force a blank line before start boundary
}
if (parts.size() == 0) {
if (allowEmpty) {
// write out a single empty body part
los.writeln(boundary); // put out boundary
los.writeln(); // put out empty line
} else {
throw new MessagingException("Empty multipart: " + contentType);
}
} else {
for (int i = 0; i < parts.size(); i++) {
los.writeln(boundary); // put out boundary
((MimeBodyPart)parts.elementAt(i)).writeTo(os);
los.writeln(); // put out empty line
}
}
// put out last boundary
los.writeln(boundary + "--");
}
/**
* 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 {@link #initializeProperties} method is called before
* parsing the data.
*
* @exception ParseException for failures parsing the message
* @exception MessagingException for other failures
* @since JavaMail 1.2
*/
protected synchronized void parse() throws MessagingException {
if (parsed)
return;
initializeProperties();
InputStream in = null;
SharedInputStream sin = null;
long start = 0, end = 0;
try {
in = ds.getInputStream();
if (!(in instanceof ByteArrayInputStream) &&
!(in instanceof BufferedInputStream) &&
!(in instanceof SharedInputStream))
in = new BufferedInputStream(in);
} catch (Exception ex) {
throw new MessagingException("No inputstream from datasource", ex);
}
if (in instanceof SharedInputStream)
sin = (SharedInputStream)in;
ContentType cType = new ContentType(contentType);
String boundary = null;
if (!ignoreExistingBoundaryParameter) {
String bp = cType.getParameter("boundary");
if (bp != null)
boundary = "--" + bp;
}
if (boundary == null && !ignoreMissingBoundaryParameter &&
!ignoreExistingBoundaryParameter)
throw new ParseException("Missing boundary parameter");
try {
// Skip and save the preamble
LineInputStream lin = streamProvider.inputLineStream(in, false);
StringBuilder preamblesb = null;
String line;
while ((line = lin.readLine()) != null) {
/*
* Strip trailing whitespace. Can't use trim method
* because it's too aggressive. Some bogus MIME
* messages will include control characters in the
* boundary string.
*/
int i;
for (i = line.length() - 1; i >= 0; i--) {
char c = line.charAt(i);
if (!(c == ' ' || c == '\t'))
break;
}
line = line.substring(0, i + 1);
if (boundary != null) {
if (line.equals(boundary))
break;
if (line.length() == boundary.length() + 2 &&
line.startsWith(boundary) && line.endsWith("--")) {
line = null; // signal end of multipart
break;
}
} else {
/*
* Boundary hasn't been defined, does this line
* look like a boundary? If so, assume it is
* the boundary and save it.
*/
if (line.length() > 2 && line.startsWith("--")) {
if (line.length() > 4 && allDashes(line)) {
/*
* The first boundary-like line we find is
* probably *not* the end-of-multipart boundary
* line. More likely it's a line full of dashes
* in the preamble text. Just keep reading.
*/
} else {
boundary = line;
break;
}
}
}
// save the preamble after skipping blank lines
if (line.length() > 0) {
// accumulate the preamble
if (preamblesb == null)
preamblesb = new StringBuilder(line.length() + 2);
preamblesb.append(line).append(System.lineSeparator());
}
}
if (preamblesb != null)
preamble = preamblesb.toString();
if (line == null) {
if (allowEmpty)
return;
else
throw new ParseException("Missing start boundary");
}
// save individual boundary bytes for comparison later
byte[] bndbytes = MimeUtility.getBytes(boundary);
int bl = bndbytes.length;
/*
* Compile Boyer-Moore parsing tables.
*/
// initialize Bad Character Shift table
int[] bcs = new int[256];
for (int i = 0; i < bl; i++)
bcs[bndbytes[i] & 0xff] = i + 1;
// initialize Good Suffix Shift table
int[] gss = new int[bl];
NEXT:
for (int i = bl; i > 0; i--) {
int j; // the beginning index of the suffix being considered
for (j = bl - 1; j >= i; j--) {
// Testing for good suffix
if (bndbytes[j] == bndbytes[j - i]) {
// bndbytes[j..len] is a good suffix
gss[j - 1] = i;
} else {
// No match. The array has already been
// filled up with correct values before.
continue NEXT;
}
}
while (j > 0)
gss[--j] = i;
}
gss[bl - 1] = 1;
/*
* Read and process body parts until we see the
* terminating boundary line (or EOF).
*/
boolean done = false;
getparts:
while (!done) {
InternetHeaders headers = null;
if (sin != null) {
start = sin.getPosition();
// skip headers
while ((line = lin.readLine()) != null && line.length() > 0)
;
if (line == null) {
if (!ignoreMissingEndBoundary)
throw new ParseException(
"missing multipart end boundary");
// assume there's just a missing end boundary
complete = false;
break getparts;
}
} else {
// collect the headers for this body part
headers = createInternetHeaders(in);
}
if (!in.markSupported())
throw new MessagingException("Stream doesn't support mark");
ByteArrayOutputStream buf = null;
// if we don't have a shared input stream, we copy the data
if (sin == null)
buf = new ByteArrayOutputStream();
else
end = sin.getPosition();
int b;
/*
* These buffers contain the bytes we're checking
* for a match. inbuf is the current buffer and
* previnbuf is the previous buffer. We need the
* previous buffer to check that we're preceeded
* by an EOL.
*/
// XXX - a smarter algorithm would use a sliding window
// over a larger buffer
byte[] inbuf = new byte[bl];
byte[] previnbuf = new byte[bl];
int inSize = 0; // number of valid bytes in inbuf
int prevSize = 0; // number of valid bytes in previnbuf
int eolLen;
boolean first = true;
/*
* Read and save the content bytes in buf.
*/
for (;;) {
in.mark(bl + 4 + 1000); // bnd + "--\r\n" + lots of LWSP
eolLen = 0;
inSize = readFully(in, inbuf, 0, bl);
if (inSize < bl) {
// hit EOF
if (!ignoreMissingEndBoundary)
throw new ParseException(
"missing multipart end boundary");
if (sin != null)
end = sin.getPosition();
complete = false;
done = true;
break;
}
// check whether inbuf contains a boundary string
int i;
for (i = bl - 1; i >= 0; i--) {
if (inbuf[i] != bndbytes[i])
break;
}
if (i < 0) { // matched all bytes
eolLen = 0;
if (!first) {
// working backwards, find out if we were preceeded
// by an EOL, and if so find its length
b = previnbuf[prevSize - 1];
if (b == '\r' || b == '\n') {
eolLen = 1;
if (b == '\n' && prevSize >= 2) {
b = previnbuf[prevSize - 2];
if (b == '\r')
eolLen = 2;
}
}
}
if (first || eolLen > 0) { // yes, preceed by EOL
if (sin != null) {
// update "end", in case this really is
// a valid boundary
end = sin.getPosition() - bl - eolLen;
}
// matched the boundary, check for last boundary
int b2 = in.read();
if (b2 == '-') {
if (in.read() == '-') {
complete = true;
done = true;
break; // ignore trailing text
}
}
// skip linear whitespace
while (b2 == ' ' || b2 == '\t')
b2 = in.read();
// check for end of line
if (b2 == '\n')
break; // got it! break out of the loop
if (b2 == '\r') {
in.mark(1);
if (in.read() != '\n')
in.reset();
break; // got it! break out of the loop
}
}
i = 0;
}
/*
* Get here if boundary didn't match,
* wasn't preceeded by EOL, or wasn't
* followed by whitespace or EOL.
*/
// compute how many bytes we can skip
int skip = Math.max(i + 1 - bcs[inbuf[i] & 0xff], gss[i]);
// want to keep at least two characters
if (skip < 2) {
// only skipping one byte, save one byte
// from previous buffer as well
// first, write out bytes we're done with
if (sin == null && prevSize > 1)
buf.write(previnbuf, 0, prevSize - 1);
in.reset();
skipFully(in, 1);
if (prevSize >= 1) { // is there a byte to save?
// yes, save one from previous and one from current
previnbuf[0] = previnbuf[prevSize - 1];
previnbuf[1] = inbuf[0];
prevSize = 2;
} else {
// no previous bytes to save, can only save current
previnbuf[0] = inbuf[0];
prevSize = 1;
}
} else {
// first, write out data from previous buffer before
// we dump it
if (prevSize > 0 && sin == null)
buf.write(previnbuf, 0, prevSize);
// all the bytes we're skipping are saved in previnbuf
prevSize = skip;
in.reset();
skipFully(in, prevSize);
// swap buffers
byte[] tmp = inbuf;
inbuf = previnbuf;
previnbuf = tmp;
}
first = false;
}
/*
* Create a MimeBody element to represent this body part.
*/
MimeBodyPart part;
if (sin != null) {
part = createMimeBodyPartIs(sin.newStream(start, end));
} else {
// write out data from previous buffer, not including EOL
if (prevSize - eolLen > 0)
buf.write(previnbuf, 0, prevSize - eolLen);
// if we didn't find a trailing boundary,
// the current buffer has data we need too
if (!complete && inSize > 0)
buf.write(inbuf, 0, inSize);
part = createMimeBodyPart(headers, buf.toByteArray());
}
super.addBodyPart(part);
}
} catch (IOException ioex) {
throw new MessagingException("IO Error", ioex);
} finally {
try {
in.close();
} catch (IOException cex) {
// ignore
}
}
parsed = true;
}
/**
* Is the string all dashes ('-')?
*/
private static boolean allDashes(String s) {
for (int i = 0; i < s.length(); i++) {
if (s.charAt(i) != '-')
return false;
}
return true;
}
/**
* Read data from the input stream to fill the buffer starting
* at the specified offset with the specified number of bytes.
* If len is zero, return zero. If at EOF, return -1. Otherwise,
* return the number of bytes read. Call the read method on the
* input stream as many times as necessary to read len bytes.
*
* @param in InputStream to read from
* @param buf buffer to read into
* @param off offset in the buffer for first byte
* @param len number of bytes to read
* @return -1 on EOF, otherwise number of bytes read
* @exception IOException on I/O errors
*/
private static int readFully(InputStream in, byte[] buf, int off, int len)
throws IOException {
if (len == 0)
return 0;
int total = 0;
while (len > 0) {
int bsize = in.read(buf, off, len);
if (bsize <= 0) // should never be zero
break;
off += bsize;
total += bsize;
len -= bsize;
}
return total > 0 ? total : -1;
}
/**
* Skip the specified number of bytes, repeatedly calling
* the skip method as necessary.
*/
private void skipFully(InputStream in, long offset) throws IOException {
while (offset > 0) {
long cur = in.skip(offset);
if (cur <= 0)
throw new EOFException("can't skip");
offset -= cur;
}
}
/**
* 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.
*
* @param is the InputStream to read the headers from
* @return an InternetHeaders object
* @exception MessagingException for failures
* @since JavaMail 1.2
*/
protected InternetHeaders createInternetHeaders(InputStream is)
throws MessagingException {
return new InternetHeaders(is);
}
/**
* 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.
*
* @param headers the headers for the body part
* @param content the content of the body part
* @return a MimeBodyPart
* @exception MessagingException for failures
* @since JavaMail 1.2
*/
protected MimeBodyPart createMimeBodyPart(InternetHeaders headers,
byte[] content) throws MessagingException {
return new MimeBodyPart(headers, content);
}
/**
* 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.
*
* @param is InputStream containing the body part
* @return a MimeBodyPart
* @exception MessagingException for failures
* @since JavaMail 1.2
*/
protected MimeBodyPart createMimeBodyPart(InputStream is)
throws MessagingException {
return new MimeBodyPart(is);
}
private MimeBodyPart createMimeBodyPartIs(InputStream is)
throws MessagingException {
try {
return createMimeBodyPart(is);
} finally {
try {
is.close();
} catch (IOException ex) {
// ignore it
}
}
}
}