jakarta.mail.internet.InternetHeaders 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.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import jakarta.mail.Header;
import jakarta.mail.MessagingException;
import jakarta.mail.util.LineInputStream;
import jakarta.mail.util.StreamProvider;
/**
* InternetHeaders is a utility class that manages RFC822 style
* headers. Given an RFC822 format message stream, it reads lines
* until the blank line that indicates end of header. The input stream
* is positioned at the start of the body. The lines are stored
* within the object and can be extracted as either Strings or
* {@link jakarta.mail.Header} objects.
*
* This class is mostly intended for service providers. MimeMessage
* and MimeBody use this class for holding their headers.
*
*
A note on RFC822 and MIME headers
*
* RFC822 and MIME header fields must contain only
* US-ASCII characters. If a header contains non US-ASCII characters,
* it must be encoded as per the rules in RFC 2047. 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.
*
* The current implementation supports the System property
* mail.mime.ignorewhitespacelines, which if set to true
* will cause a line containing only whitespace to be considered
* a blank line terminating the header.
*
* @see jakarta.mail.internet.MimeUtility
* @author John Mani
* @author Bill Shannon
*/
public class InternetHeaders {
private static final boolean ignoreWhitespaceLines =
MimeUtility.getBooleanSystemProperty("mail.mime.ignorewhitespacelines",
false);
/**
* An individual internet header. This class is only used by
* subclasses of InternetHeaders.
*
* An InternetHeader object with a null value is used as a placeholder
* for headers of that name, to preserve the order of headers.
* A placeholder InternetHeader object with a name of ":" marks
* the location in the list of headers where new headers are
* added by default.
*
* @since JavaMail 1.4
*/
protected static final class InternetHeader extends Header {
/*
* Note that the value field from the superclass
* isn't used in this class. We extract the value
* from the line field as needed. We store the line
* rather than just the value to ensure that we can
* get back the exact original line, with the original
* whitespace, etc.
*/
String line; // the entire RFC822 header "line",
// or null if placeholder
/**
* Constructor that takes a line and splits out
* the header name.
*
* @param l the header line
*/
public InternetHeader(String l) {
super("", ""); // XXX - we'll change it later
int i = l.indexOf(':');
if (i < 0) {
// should never happen
name = l.trim();
} else {
name = l.substring(0, i).trim();
}
line = l;
}
/**
* Constructor that takes a header name and value.
*
* @param n the name of the header
* @param v the value of the header
*/
public InternetHeader(String n, String v) {
super(n, "");
if (v != null)
line = n + ": " + v;
else
line = null;
}
/**
* Return the "value" part of the header line.
*/
@Override
public String getValue() {
int i = line.indexOf(':');
if (i < 0)
return line;
// skip whitespace after ':'
int j;
for (j = i + 1; j < line.length(); j++) {
char c = line.charAt(j);
if (!(c == ' ' || c == '\t' || c == '\r' || c == '\n'))
break;
}
return line.substring(j);
}
}
/*
* The enumeration object used to enumerate an
* InternetHeaders object. Can return
* either a String or a Header object.
*/
static class MatchEnum {
private Iterator e; // enum object of headers List
// XXX - is this overkill? should we step through in index
// order instead?
private String names[]; // names to match, or not
private boolean match; // return matching headers?
private boolean want_line; // return header lines?
private InternetHeader next_header; // the next header to be returned
/*
* Constructor. Initialize the enumeration for the entire
* List of headers, the set of headers, whether to return
* matching or non-matching headers, and whether to return
* header lines or Header objects.
*/
MatchEnum(List v, String n[], boolean m, boolean l) {
e = v.iterator();
names = n;
match = m;
want_line = l;
next_header = null;
}
/*
* Any more elements in this enumeration?
*/
public boolean hasMoreElements() {
// if necessary, prefetch the next matching header,
// and remember it.
if (next_header == null)
next_header = nextMatch();
return next_header != null;
}
/*
* Return the next element.
*/
public Object nextElement() {
if (next_header == null)
next_header = nextMatch();
if (next_header == null)
throw new NoSuchElementException("No more headers");
InternetHeader h = next_header;
next_header = null;
if (want_line)
return h.line;
else
return new Header(h.getName(), h.getValue());
}
/*
* Return the next Header object according to the match
* criteria, or null if none left.
*/
private InternetHeader nextMatch() {
next:
while (e.hasNext()) {
InternetHeader h = e.next();
// skip "place holder" headers
if (h.line == null)
continue;
// if no names to match against, return appropriately
if (names == null)
return match ? null : h;
// check whether this header matches any of the names
for (int i = 0; i < names.length; i++) {
if (names[i].equalsIgnoreCase(h.getName())) {
if (match)
return h;
else
// found a match, but we're
// looking for non-matches.
// try next header.
continue next;
}
}
// found no matches. if that's what we wanted, return it.
if (!match)
return h;
}
return null;
}
}
static class MatchStringEnum extends MatchEnum
implements Enumeration {
MatchStringEnum(List v, String[] n, boolean m) {
super(v, n, m, true);
}
@Override
public String nextElement() {
return (String) super.nextElement();
}
}
static class MatchHeaderEnum extends MatchEnum
implements Enumeration {
MatchHeaderEnum(List v, String[] n, boolean m) {
super(v, n, m, false);
}
@Override
public Header nextElement() {
return (Header) super.nextElement();
}
}
/**
* The actual list of Headers, including placeholder entries.
* Placeholder entries are Headers with a null value and
* are never seen by clients of the InternetHeaders class.
* Placeholder entries are used to keep track of the preferred
* order of headers. Headers are never actually removed from
* the list, they're converted into placeholder entries.
* New headers are added after existing headers of the same name
* (or before in the case of Received and
* Return-Path headers). If no existing header
* or placeholder for the header is found, new headers are
* added after the special placeholder with the name ":".
*
* @since JavaMail 1.4
*/
protected List headers;
/**
* Create an empty InternetHeaders object. Placeholder entries
* are inserted to indicate the preferred order of headers.
*/
public InternetHeaders() {
headers = new ArrayList<>(40);
headers.add(new InternetHeader("Return-Path", null));
headers.add(new InternetHeader("Received", null));
headers.add(new InternetHeader("Resent-Date", null));
headers.add(new InternetHeader("Resent-From", null));
headers.add(new InternetHeader("Resent-Sender", null));
headers.add(new InternetHeader("Resent-To", null));
headers.add(new InternetHeader("Resent-Cc", null));
headers.add(new InternetHeader("Resent-Bcc", null));
headers.add(new InternetHeader("Resent-Message-Id", null));
headers.add(new InternetHeader("Date", null));
headers.add(new InternetHeader("From", null));
headers.add(new InternetHeader("Sender", null));
headers.add(new InternetHeader("Reply-To", null));
headers.add(new InternetHeader("To", null));
headers.add(new InternetHeader("Cc", null));
headers.add(new InternetHeader("Bcc", null));
headers.add(new InternetHeader("Message-Id", null));
headers.add(new InternetHeader("In-Reply-To", null));
headers.add(new InternetHeader("References", null));
headers.add(new InternetHeader("Subject", null));
headers.add(new InternetHeader("Comments", null));
headers.add(new InternetHeader("Keywords", null));
headers.add(new InternetHeader("Errors-To", null));
headers.add(new InternetHeader("MIME-Version", null));
headers.add(new InternetHeader("Content-Type", null));
headers.add(new InternetHeader("Content-Transfer-Encoding", null));
headers.add(new InternetHeader("Content-MD5", null));
headers.add(new InternetHeader(":", null));
headers.add(new InternetHeader("Content-Length", null));
headers.add(new InternetHeader("Status", null));
}
/**
* Read and parse the given RFC822 message stream till the
* blank line separating the header from the body. The input
* stream is left positioned at the start of the body. The
* header lines are stored internally.
*
* For efficiency, wrap a BufferedInputStream around the actual
* input stream and pass it as the parameter.
*
* No placeholder entries are inserted; the original order of
* the headers is preserved.
*
* @param is RFC822 input stream
* @exception MessagingException for any I/O error reading the stream
*/
public InternetHeaders(InputStream is) throws MessagingException {
this(is, false);
}
/**
* Read and parse the given RFC822 message stream till the
* blank line separating the header from the body. The input
* stream is left positioned at the start of the body. The
* header lines are stored internally.
*
* For efficiency, wrap a BufferedInputStream around the actual
* input stream and pass it as the parameter.
*
* No placeholder entries are inserted; the original order of
* the headers is preserved.
*
* @param is RFC822 input stream
* @param allowutf8 if UTF-8 encoded headers are allowed
* @exception MessagingException for any I/O error reading the stream
* @since JavaMail 1.6
*/
public InternetHeaders(InputStream is, boolean allowutf8)
throws MessagingException {
headers = new ArrayList<>(40);
load(is, allowutf8);
}
/**
* Read and parse the given RFC822 message stream till the
* blank line separating the header from the body. Store the
* header lines inside this InternetHeaders object. The order
* of header lines is preserved.
*
* Note that the header lines are added into this InternetHeaders
* object, so any existing headers in this object will not be
* affected. Headers are added to the end of the existing list
* of headers, in order.
*
* @param is RFC822 input stream
* @exception MessagingException for any I/O error reading the stream
*/
public void load(InputStream is) throws MessagingException {
load(is, false);
}
/**
* Read and parse the given RFC822 message stream till the
* blank line separating the header from the body. Store the
* header lines inside this InternetHeaders object. The order
* of header lines is preserved.
*
* Note that the header lines are added into this InternetHeaders
* object, so any existing headers in this object will not be
* affected. Headers are added to the end of the existing list
* of headers, in order.
*
* @param is RFC822 input stream
* @param allowutf8 if UTF-8 encoded headers are allowed
* @exception MessagingException for any I/O error reading the stream
* @since JavaMail 1.6
*/
public void load(InputStream is, boolean allowutf8)
throws MessagingException {
// Read header lines until a blank line. It is valid
// to have BodyParts with no header lines.
String line;
LineInputStream lis = StreamProvider.provider().inputLineStream(is, allowutf8);
String prevline = null; // the previous header line, as a string
// a buffer to accumulate the header in, when we know it's needed
StringBuilder lineBuffer = new StringBuilder();
try {
// if the first line being read is a continuation line,
// we ignore it if it's otherwise empty or we treat it as
// a non-continuation line if it has non-whitespace content
boolean first = true;
do {
line = lis.readLine();
if (line != null &&
(line.startsWith(" ") || line.startsWith("\t"))) {
// continuation of header
if (prevline != null) {
lineBuffer.append(prevline);
prevline = null;
}
if (first) {
String lt = line.trim();
if (lt.length() > 0)
lineBuffer.append(lt);
} else {
if (lineBuffer.length() > 0)
lineBuffer.append("\r\n");
lineBuffer.append(line);
}
} else {
// new header
if (prevline != null)
addHeaderLine(prevline);
else if (lineBuffer.length() > 0) {
// store previous header first
addHeaderLine(lineBuffer.toString());
lineBuffer.setLength(0);
}
prevline = line;
}
first = false;
} while (line != null && !isEmpty(line));
} catch (IOException ioex) {
throw new MessagingException("Error in input stream", ioex);
}
}
/**
* Is this line an empty (blank) line?
*/
private static final boolean isEmpty(String line) {
return line.length() == 0 ||
(ignoreWhitespaceLines && line.trim().length() == 0);
}
/**
* Return all the values for the specified header. The
* values are String objects. Returns null
* if no headers with the specified name exist.
*
* @param name header name
* @return array of header values, or null if none
*/
public String[] getHeader(String name) {
Iterator e = headers.iterator();
// XXX - should we just step through in index order?
List v = new ArrayList<>(); // accumulate return values
while (e.hasNext()) {
InternetHeader h = e.next();
if (name.equalsIgnoreCase(h.getName()) && h.line != null) {
v.add(h.getValue());
}
}
if (v.size() == 0)
return (null);
// convert List to an array for return
String r[] = new String[v.size()];
r = v.toArray(r);
return (r);
}
/**
* 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. Returns null
* if no headers with the specified name exist.
*
* @param name header name
* @param delimiter delimiter
* @return the value fields for all headers with
* this name, or null if none
*/
public String getHeader(String name, String delimiter) {
String s[] = getHeader(name);
if (s == null)
return null;
if ((s.length == 1) || delimiter == null)
return s[0];
StringBuilder r = new StringBuilder(s[0]);
for (int i = 1; i < s.length; i++) {
r.append(delimiter);
r.append(s[i]);
}
return r.toString();
}
/**
* Change the first header line that matches name
* to have value, adding a new header if no existing header
* matches. Remove all matching headers but the first.
*
* Note that RFC822 headers can only contain US-ASCII characters
*
* @param name header name
* @param value header value
*/
public void setHeader(String name, String value) {
boolean found = false;
for (int i = 0; i < headers.size(); i++) {
InternetHeader h = headers.get(i);
if (name.equalsIgnoreCase(h.getName())) {
if (!found) {
int j;
if (h.line != null && (j = h.line.indexOf(':')) >= 0) {
h.line = h.line.substring(0, j + 1) + " " + value;
// preserves capitalization, spacing
} else {
h.line = name + ": " + value;
}
found = true;
} else {
headers.remove(i);
i--; // have to look at i again
}
}
}
if (!found) {
addHeader(name, value);
}
}
/**
* Add a header with the specified name and value to the header list.
*
* The current implementation knows about the preferred order of most
* well-known headers and will insert headers in that order. In
* addition, it knows that Received headers should be
* inserted in reverse order (newest before oldest), and that they
* should appear at the beginning of the headers, preceeded only by
* a possible Return-Path header.
*
* Note that RFC822 headers can only contain US-ASCII characters.
*
* @param name header name
* @param value header value
*/
public void addHeader(String name, String value) {
int pos = headers.size();
boolean addReverse =
name.equalsIgnoreCase("Received") ||
name.equalsIgnoreCase("Return-Path");
if (addReverse)
pos = 0;
for (int i = headers.size() - 1; i >= 0; i--) {
InternetHeader h = headers.get(i);
if (name.equalsIgnoreCase(h.getName())) {
if (addReverse) {
pos = i;
} else {
headers.add(i + 1, new InternetHeader(name, value));
return;
}
}
// marker for default place to add new headers
if (!addReverse && h.getName().equals(":"))
pos = i;
}
headers.add(pos, new InternetHeader(name, value));
}
/**
* Remove all header entries that match the given name
* @param name header name
*/
public void removeHeader(String name) {
for (int i = 0; i < headers.size(); i++) {
InternetHeader h = headers.get(i);
if (name.equalsIgnoreCase(h.getName())) {
h.line = null;
//headers.remove(i);
//i--; // have to look at i again
}
}
}
/**
* Return all the headers as an Enumeration of
* {@link jakarta.mail.Header} objects.
*
* @return Enumeration of Header objects
*/
public Enumeration getAllHeaders() {
return (new MatchHeaderEnum(headers, null, false));
}
/**
* Return all matching {@link jakarta.mail.Header} objects.
*
* @param names the headers to return
* @return Enumeration of matching Header objects
*/
public Enumeration getMatchingHeaders(String[] names) {
return (new MatchHeaderEnum(headers, names, true));
}
/**
* Return all non-matching {@link jakarta.mail.Header} objects.
*
* @param names the headers to not return
* @return Enumeration of non-matching Header objects
*/
public Enumeration getNonMatchingHeaders(String[] names) {
return (new MatchHeaderEnum(headers, names, false));
}
/**
* Add an RFC822 header line to the header store.
* If the line starts with a space or tab (a continuation line),
* add it to the last header line in the list. Otherwise,
* append the new header line to the list.
*
* Note that RFC822 headers can only contain US-ASCII characters
*
* @param line raw RFC822 header line
*/
public void addHeaderLine(String line) {
try {
char c = line.charAt(0);
if (c == ' ' || c == '\t') {
InternetHeader h = headers.get(headers.size() - 1);
h.line += "\r\n" + line;
} else
headers.add(new InternetHeader(line));
} catch (StringIndexOutOfBoundsException e) {
// line is empty, ignore it
return;
} catch (NoSuchElementException e) {
// XXX - list is empty?
}
}
/**
* Return all the header lines as an Enumeration of Strings.
*
* @return Enumeration of Strings of all header lines
*/
public Enumeration getAllHeaderLines() {
return (getNonMatchingHeaderLines(null));
}
/**
* Return all matching header lines as an Enumeration of Strings.
*
* @param names the headers to return
* @return Enumeration of Strings of all matching header lines
*/
public Enumeration getMatchingHeaderLines(String[] names) {
return (new MatchStringEnum(headers, names, true));
}
/**
* Return all non-matching header lines
*
* @param names the headers to not return
* @return Enumeration of Strings of all non-matching header lines
*/
public Enumeration getNonMatchingHeaderLines(String[] names) {
return (new MatchStringEnum(headers, names, false));
}
}