The MailcapCommandMap.java Java example source code
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
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*
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
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package javax.activation;
import java.util.*;
import java.io.*;
import java.net.*;
import com.sun.activation.registries.MailcapFile;
import com.sun.activation.registries.LogSupport;
/**
* MailcapCommandMap extends the CommandMap
* abstract class. It implements a CommandMap whose configuration
* is based on mailcap files
* (<A HREF="http://www.ietf.org/rfc/rfc1524.txt">RFC 1524).
* The MailcapCommandMap can be configured both programmatically
* and via configuration files.
* <p>
* <b>Mailcap file search order:
* The MailcapCommandMap looks in various places in the user's
* system for mailcap file entries. When requests are made
* to search for commands in the MailcapCommandMap, it searches
* mailcap files in the following order:
* <p>
* <ol>
* <li> Programatically added entries to the MailcapCommandMap instance.
* <li> The file .mailcap in the user's home directory.
* <li> The file <java.home>/lib/mailcap.
* <li> The file or resources named META-INF/mailcap.
* <li> The file or resource named META-INF/mailcap.default
* (usually found only in the <code>activation.jar file).
* </ol>
* <p>
* <b>Mailcap file format:
*
* Mailcap files must conform to the mailcap
* file specification (RFC 1524, <i>A User Agent Configuration Mechanism
* For Multimedia Mail Format Information</i>).
* The file format consists of entries corresponding to
* particular MIME types. In general, the specification
* specifies <i>applications for clients to use when they
* themselves cannot operate on the specified MIME type. The
* MailcapCommandMap extends this specification by using a parameter mechanism
* in mailcap files that allows JavaBeans(tm) components to be specified as
* corresponding to particular commands for a MIME type.<p>
*
* When a mailcap file is
* parsed, the MailcapCommandMap recognizes certain parameter signatures,
* specifically those parameter names that begin with <code>x-java-.
* The MailcapCommandMap uses this signature to find
* command entries for inclusion into its registries.
* Parameter names with the form <code>x-java-<name>
* are read by the MailcapCommandMap as identifying a command
* with the name <i>name. When the name is
* content-handler</code> the MailcapCommandMap recognizes the class
* signified by this parameter as a <i>DataContentHandler.
* All other commands are handled generically regardless of command
* name. The command implementation is specified by a fully qualified
* class name of a JavaBean(tm) component. For example; a command for viewing
* some data can be specified as: <code>x-java-view=com.foo.ViewBean.
*
* When the command name is <code>fallback-entry, the value of
* the command may be <code>true or false. An
* entry for a MIME type that includes a parameter of
* <code>x-java-fallback-entry=true defines fallback commands
* for that MIME type that will only be used if no non-fallback entry
* can be found. For example, an entry of the form <code>text/*; ;
* x-java-fallback-entry=true; x-java-view=com.sun.TextViewer</code>
* specifies a view command to be used for any text MIME type. This
* view command would only be used if a non-fallback view command for
* the MIME type could not be found.<p>
*
* MailcapCommandMap aware mailcap files have the
* following general form:<p>
* <code>
* # Comments begin with a '#' and continue to the end of the line.<br>
* <mime type>; ; <parameter list><br>
* # Where a parameter list consists of one or more parameters,<br>
* # where parameters look like: x-java-view=com.sun.TextViewer<br>
* # and a parameter list looks like: <br>
* text/plain; ; x-java-view=com.sun.TextViewer; x-java-edit=com.sun.TextEdit
* <br>
* # Note that mailcap entries that do not contain 'x-java' parameters<br>
* # and comply to RFC 1524 are simply ignored:<br>
* image/gif; /usr/dt/bin/sdtimage %s<br>
*
* </code>
* <p>
*
* @author Bart Calder
* @author Bill Shannon
*
* @since 1.6
*/
public class MailcapCommandMap extends CommandMap {
/*
* We manage a collection of databases, searched in order.
* The default database is shared between all instances
* of this class.
* XXX - Can we safely share more databases between instances?
*/
private static MailcapFile defDB = null;
private MailcapFile[] DB;
private static final int PROG = 0; // programmatically added entries
/**
* The default Constructor.
*/
public MailcapCommandMap() {
super();
List dbv = new ArrayList(5); // usually 5 or less databases
MailcapFile mf = null;
dbv.add(null); // place holder for PROG entry
LogSupport.log("MailcapCommandMap: load HOME");
try {
String user_home = System.getProperty("user.home");
if (user_home != null) {
String path = user_home + File.separator + ".mailcap";
mf = loadFile(path);
if (mf != null)
dbv.add(mf);
}
} catch (SecurityException ex) {}
LogSupport.log("MailcapCommandMap: load SYS");
try {
// check system's home
String system_mailcap = System.getProperty("java.home") +
File.separator + "lib" + File.separator + "mailcap";
mf = loadFile(system_mailcap);
if (mf != null)
dbv.add(mf);
} catch (SecurityException ex) {}
LogSupport.log("MailcapCommandMap: load JAR");
// load from the app's jar file
loadAllResources(dbv, "META-INF/mailcap");
LogSupport.log("MailcapCommandMap: load DEF");
synchronized (MailcapCommandMap.class) {
// see if another instance has created this yet.
if (defDB == null)
defDB = loadResource("/META-INF/mailcap.default");
}
if (defDB != null)
dbv.add(defDB);
DB = new MailcapFile[dbv.size()];
DB = (MailcapFile[])dbv.toArray(DB);
}
/**
* Load from the named resource.
*/
private MailcapFile loadResource(String name) {
InputStream clis = null;
try {
clis = SecuritySupport.getResourceAsStream(this.getClass(), name);
if (clis != null) {
MailcapFile mf = new MailcapFile(clis);
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: successfully loaded " +
"mailcap file: " + name);
return mf;
} else {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: not loading " +
"mailcap file: " + name);
}
} catch (IOException e) {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: can't load " + name, e);
} catch (SecurityException sex) {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: can't load " + name, sex);
} finally {
try {
if (clis != null)
clis.close();
} catch (IOException ex) { } // ignore it
}
return null;
}
/**
* Load all of the named resource.
*/
private void loadAllResources(List v, String name) {
boolean anyLoaded = false;
try {
URL[] urls;
ClassLoader cld = null;
// First try the "application's" class loader.
cld = SecuritySupport.getContextClassLoader();
if (cld == null)
cld = this.getClass().getClassLoader();
if (cld != null)
urls = SecuritySupport.getResources(cld, name);
else
urls = SecuritySupport.getSystemResources(name);
if (urls != null) {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: getResources");
for (int i = 0; i < urls.length; i++) {
URL url = urls[i];
InputStream clis = null;
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: URL " + url);
try {
clis = SecuritySupport.openStream(url);
if (clis != null) {
v.add(new MailcapFile(clis));
anyLoaded = true;
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: " +
"successfully loaded " +
"mailcap file from URL: " +
url);
} else {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: " +
"not loading mailcap " +
"file from URL: " + url);
}
} catch (IOException ioex) {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: can't load " +
url, ioex);
} catch (SecurityException sex) {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: can't load " +
url, sex);
} finally {
try {
if (clis != null)
clis.close();
} catch (IOException cex) { }
}
}
}
} catch (Exception ex) {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: can't load " + name, ex);
}
// if failed to load anything, fall back to old technique, just in case
if (!anyLoaded) {
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: !anyLoaded");
MailcapFile mf = loadResource("/" + name);
if (mf != null)
v.add(mf);
}
}
/**
* Load from the named file.
*/
private MailcapFile loadFile(String name) {
MailcapFile mtf = null;
try {
mtf = new MailcapFile(name);
} catch (IOException e) {
// e.printStackTrace();
}
return mtf;
}
/**
* Constructor that allows the caller to specify the path
* of a <i>mailcap file.
*
* @param fileName The name of the <i>mailcap file to open
* @exception IOException if the file can't be accessed
*/
public MailcapCommandMap(String fileName) throws IOException {
this();
if (LogSupport.isLoggable())
LogSupport.log("MailcapCommandMap: load PROG from " + fileName);
if (DB[PROG] == null) {
DB[PROG] = new MailcapFile(fileName);
}
}
/**
* Constructor that allows the caller to specify an <i>InputStream
* containing a mailcap file.
*
* @param is InputStream of the <i>mailcap file to open
*/
public MailcapCommandMap(InputStream is) {
this();
LogSupport.log("MailcapCommandMap: load PROG");
if (DB[PROG] == null) {
try {
DB[PROG] = new MailcapFile(is);
} catch (IOException ex) {
// XXX - should throw it
}
}
}
/**
* Get the preferred command list for a MIME Type. The MailcapCommandMap
* searches the mailcap files as described above under
* <i>Mailcap file search order.
*
* The result of the search is a proper subset of available
* commands in all mailcap files known to this instance of
* MailcapCommandMap. The first entry for a particular command
* is considered the preferred command.
*
* @param mimeType the MIME type
* @return the CommandInfo objects representing the preferred commands.
*/
public synchronized CommandInfo[] getPreferredCommands(String mimeType) {
List cmdList = new ArrayList();
if (mimeType != null)
mimeType = mimeType.toLowerCase(Locale.ENGLISH);
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
Map cmdMap = DB[i].getMailcapList(mimeType);
if (cmdMap != null)
appendPrefCmdsToList(cmdMap, cmdList);
}
// now add the fallback commands
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
Map cmdMap = DB[i].getMailcapFallbackList(mimeType);
if (cmdMap != null)
appendPrefCmdsToList(cmdMap, cmdList);
}
CommandInfo[] cmdInfos = new CommandInfo[cmdList.size()];
cmdInfos = (CommandInfo[])cmdList.toArray(cmdInfos);
return cmdInfos;
}
/**
* Put the commands that are in the hash table, into the list.
*/
private void appendPrefCmdsToList(Map cmdHash, List cmdList) {
Iterator verb_enum = cmdHash.keySet().iterator();
while (verb_enum.hasNext()) {
String verb = (String)verb_enum.next();
if (!checkForVerb(cmdList, verb)) {
List cmdList2 = (List)cmdHash.get(verb); // get the list
String className = (String)cmdList2.get(0);
cmdList.add(new CommandInfo(verb, className));
}
}
}
/**
* Check the cmdList to see if this command exists, return
* true if the verb is there.
*/
private boolean checkForVerb(List cmdList, String verb) {
Iterator ee = cmdList.iterator();
while (ee.hasNext()) {
String enum_verb =
(String)((CommandInfo)ee.next()).getCommandName();
if (enum_verb.equals(verb))
return true;
}
return false;
}
/**
* Get all the available commands in all mailcap files known to
* this instance of MailcapCommandMap for this MIME type.
*
* @param mimeType the MIME type
* @return the CommandInfo objects representing all the commands.
*/
public synchronized CommandInfo[] getAllCommands(String mimeType) {
List cmdList = new ArrayList();
if (mimeType != null)
mimeType = mimeType.toLowerCase(Locale.ENGLISH);
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
Map cmdMap = DB[i].getMailcapList(mimeType);
if (cmdMap != null)
appendCmdsToList(cmdMap, cmdList);
}
// now add the fallback commands
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
Map cmdMap = DB[i].getMailcapFallbackList(mimeType);
if (cmdMap != null)
appendCmdsToList(cmdMap, cmdList);
}
CommandInfo[] cmdInfos = new CommandInfo[cmdList.size()];
cmdInfos = (CommandInfo[])cmdList.toArray(cmdInfos);
return cmdInfos;
}
/**
* Put the commands that are in the hash table, into the list.
*/
private void appendCmdsToList(Map typeHash, List cmdList) {
Iterator verb_enum = typeHash.keySet().iterator();
while (verb_enum.hasNext()) {
String verb = (String)verb_enum.next();
List cmdList2 = (List)typeHash.get(verb);
Iterator cmd_enum = ((List)cmdList2).iterator();
while (cmd_enum.hasNext()) {
String cmd = (String)cmd_enum.next();
cmdList.add(new CommandInfo(verb, cmd));
// cmdList.add(0, new CommandInfo(verb, cmd));
}
}
}
/**
* Get the command corresponding to <code>cmdName for the MIME type.
*
* @param mimeType the MIME type
* @param cmdName the command name
* @return the CommandInfo object corresponding to the command.
*/
public synchronized CommandInfo getCommand(String mimeType,
String cmdName) {
if (mimeType != null)
mimeType = mimeType.toLowerCase(Locale.ENGLISH);
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
Map cmdMap = DB[i].getMailcapList(mimeType);
if (cmdMap != null) {
// get the cmd list for the cmd
List v = (List)cmdMap.get(cmdName);
if (v != null) {
String cmdClassName = (String)v.get(0);
if (cmdClassName != null)
return new CommandInfo(cmdName, cmdClassName);
}
}
}
// now try the fallback list
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
Map cmdMap = DB[i].getMailcapFallbackList(mimeType);
if (cmdMap != null) {
// get the cmd list for the cmd
List v = (List)cmdMap.get(cmdName);
if (v != null) {
String cmdClassName = (String)v.get(0);
if (cmdClassName != null)
return new CommandInfo(cmdName, cmdClassName);
}
}
}
return null;
}
/**
* Add entries to the registry. Programmatically
* added entries are searched before other entries.<p>
*
* The string that is passed in should be in mailcap
* format.
*
* @param mail_cap a correctly formatted mailcap string
*/
public synchronized void addMailcap(String mail_cap) {
// check to see if one exists
LogSupport.log("MailcapCommandMap: add to PROG");
if (DB[PROG] == null)
DB[PROG] = new MailcapFile();
DB[PROG].appendToMailcap(mail_cap);
}
/**
* Return the DataContentHandler for the specified MIME type.
*
* @param mimeType the MIME type
* @return the DataContentHandler
*/
public synchronized DataContentHandler createDataContentHandler(
String mimeType) {
if (LogSupport.isLoggable())
LogSupport.log(
"MailcapCommandMap: createDataContentHandler for " + mimeType);
if (mimeType != null)
mimeType = mimeType.toLowerCase(Locale.ENGLISH);
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
if (LogSupport.isLoggable())
LogSupport.log(" search DB #" + i);
Map cmdMap = DB[i].getMailcapList(mimeType);
if (cmdMap != null) {
List v = (List)cmdMap.get("content-handler");
if (v != null) {
String name = (String)v.get(0);
DataContentHandler dch = getDataContentHandler(name);
if (dch != null)
return dch;
}
}
}
// now try the fallback entries
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
if (LogSupport.isLoggable())
LogSupport.log(" search fallback DB #" + i);
Map cmdMap = DB[i].getMailcapFallbackList(mimeType);
if (cmdMap != null) {
List v = (List)cmdMap.get("content-handler");
if (v != null) {
String name = (String)v.get(0);
DataContentHandler dch = getDataContentHandler(name);
if (dch != null)
return dch;
}
}
}
return null;
}
private DataContentHandler getDataContentHandler(String name) {
if (LogSupport.isLoggable())
LogSupport.log(" got content-handler");
if (LogSupport.isLoggable())
LogSupport.log(" class " + name);
try {
ClassLoader cld = null;
// First try the "application's" class loader.
cld = SecuritySupport.getContextClassLoader();
if (cld == null)
cld = this.getClass().getClassLoader();
Class cl = null;
try {
cl = cld.loadClass(name);
} catch (Exception ex) {
// if anything goes wrong, do it the old way
cl = Class.forName(name);
}
if (cl != null) // XXX - always true?
return (DataContentHandler)cl.newInstance();
} catch (IllegalAccessException e) {
if (LogSupport.isLoggable())
LogSupport.log("Can't load DCH " + name, e);
} catch (ClassNotFoundException e) {
if (LogSupport.isLoggable())
LogSupport.log("Can't load DCH " + name, e);
} catch (InstantiationException e) {
if (LogSupport.isLoggable())
LogSupport.log("Can't load DCH " + name, e);
}
return null;
}
/**
* Get all the MIME types known to this command map.
*
* @return array of MIME types as strings
* @since JAF 1.1
*/
public synchronized String[] getMimeTypes() {
List mtList = new ArrayList();
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
String[] ts = DB[i].getMimeTypes();
if (ts != null) {
for (int j = 0; j < ts.length; j++) {
// eliminate duplicates
if (!mtList.contains(ts[j]))
mtList.add(ts[j]);
}
}
}
String[] mts = new String[mtList.size()];
mts = (String[])mtList.toArray(mts);
return mts;
}
/**
* Get the native commands for the given MIME type.
* Returns an array of strings where each string is
* an entire mailcap file entry. The application
* will need to parse the entry to extract the actual
* command as well as any attributes it needs. See
* <A HREF="http://www.ietf.org/rfc/rfc1524.txt">RFC 1524
* for details of the mailcap entry syntax. Only mailcap
* entries that specify a view command for the specified
* MIME type are returned.
*
* @return array of native command entries
* @since JAF 1.1
*/
public synchronized String[] getNativeCommands(String mimeType) {
List cmdList = new ArrayList();
if (mimeType != null)
mimeType = mimeType.toLowerCase(Locale.ENGLISH);
for (int i = 0; i < DB.length; i++) {
if (DB[i] == null)
continue;
String[] cmds = DB[i].getNativeCommands(mimeType);
if (cmds != null) {
for (int j = 0; j < cmds.length; j++) {
// eliminate duplicates
if (!cmdList.contains(cmds[j]))
cmdList.add(cmds[j]);
}
}
}
String[] cmds = new String[cmdList.size()];
cmds = (String[])cmdList.toArray(cmds);
return cmds;
}
/**
* for debugging...
*
public static void main(String[] argv) throws Exception {
MailcapCommandMap map = new MailcapCommandMap();
CommandInfo[] cmdInfo;
cmdInfo = map.getPreferredCommands(argv[0]);
System.out.println("Preferred Commands:");
for (int i = 0; i < cmdInfo.length; i++)
System.out.println("Command " + cmdInfo[i].getCommandName() + " [" +
cmdInfo[i].getCommandClass() + "]");
cmdInfo = map.getAllCommands(argv[0]);
System.out.println();
System.out.println("All Commands:");
for (int i = 0; i < cmdInfo.length; i++)
System.out.println("Command " + cmdInfo[i].getCommandName() + " [" +
cmdInfo[i].getCommandClass() + "]");
DataContentHandler dch = map.createDataContentHandler(argv[0]);
if (dch != null)
System.out.println("DataContentHandler " +
dch.getClass().toString());
System.exit(0);
}
*/
}
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