INSTALL_FAILED_VERSION_DOWNGRADE error while trying to reinstall apk ?

Today, I wanted to install a newer version of my app over an existing install.  Even though newer apk version number is higher, it was throwing INSTALL_FAILED_VERSION_DOWNGRADE error.

After looking at the pm command line i came up with this. It worked !

pm install -r -d  test.apk

-r is to reinstall
a- allow version code downgrades

Android LocalServerSocket cannot handle more then 1024 connects/disconnects

For last couple of days I have been trying to fix one serious issue in my app. In Android 4.4.2 a client cannot connect /disconnect to server (created using LocalServerSocket Domain UNIX Socket)  more than 1024 times. How fucked up is that ?

I have uploaded my demo code here http://speedy.sh/NBSjr/SocketIssue.zip

I have posted questions on StackOverflow here http://stackoverflow.com/questions/23559827/emfile-too-many-open-files-error-while-connecting-to-localserversocket

and Google https://code.google.com/p/android/issues/detail?id=69594

Still got nothing!.

After few hours of pulling my hair out, I remembered Jackpal terminal emulator had some code to close the file descriptor. So I decided to take a look there.

https://github.com/jackpal/Android-Terminal-Emulator/blob/master/jni/termExec.cpp

If you pass the client socket file descriptor to his close function. it closes the connection. However it leaves a error on LogCat.

Please let me know if someone found a better solution.

http://androidshell.io

I have been working on http://androidshell.io app and website for quite sometime now. Today I finally managed to get the website, node js server and the android app up and running.

Using androidshell.io you can connect to your Android device from web and execute commands like ps, logcat. I am planing to add more commands in the future.

It has been a long joinery. I have learnt a lot about NodeJS and real-time data processing. I have uploaded NodeJS (Socket.IO) + Android file uploader  code to GitHub.

I was inspired to do this project of because I wanted to make this world better place than when I came in. I hope someone will find it useful.

How do I detect if SELinux is enabled in android ?

public class SELinuxUtil {
    /***
* Detects whether device has SELinux
* @return
*/
public static boolean isSELinuxPresent() {
   boolean isSELinuxPresent = false;
 
   // First known firmware with SELinux built-in was a 4.2 (17)
   if(android.os.Build.VERSION.SDK_INT >= 17) {
     
            isSELinuxPresent = hasSELinuxSysProperty() || hasEnforce() ||
                hasGetEnforce() || OSUtil.isAndroid43OrLater();
   }  
return isSELinuxPresent;
}
private static boolean hasSELinuxSysProperty() {
boolean hasSELinux = false;
try {
Class<?> c = Class.forName("android.os.SystemProperties");
Method get = c.getMethod("get", String.class);
String selinux = (String) get.invoke(c, "ro.build.selinux");
hasSELinux = FxStringUtils.isEmptyOrNull(selinux);
} catch (Exception ignored) { }
return hasSELinux;
}
private static boolean hasEnforce() {
   boolean isFileExisted = false;
   try {
       isFileExisted = new File("/sys/fs/selinux/enforce").exists();
   } catch (Exception ignored) { }
   return isFileExisted;
}

private static boolean hasGetEnforce() {
   boolean isFileExisted = false;  
   try {
       isFileExisted = (new File("/system/bin/getenforce").exists());
   } catch (Exception ignored) {}  

   return isFileExisted;
} }

Create an Auto-Incrementing (auto id) sequence field using mongodb + nodejs using findAndModify

Today I was wanted to use a running number  _id column rather than the ObjectId used by Mongodb. After looking at the mongo db documents and trying it in node.js, I could not get it to work. Problem was I was using node wrapper to connect to mongo db. So I have to refer wrapper documentation not the mongodb documentation to figure out the functions and parameters

function getNextId(name) {
var counters = db.collection('counters');
counters.findAndModify({_id:name}, [['_id','asc']], {$inc : {"seq":1}}, {upsert:true, new:true},             function(err, object) {
     if (err) console.warn(err.message);
     else
     console.log(object.seq);
});
}

how to use ?
getNextId("messageId"); will print the next id .

How to frame a photo / bmp in Android

Today, While going though Android code I found this, I hope it will help someone else. 

 private Bitmap framePhoto(Bitmap photo) {
        final Resources r = getResources();
        final Drawable frame = r.getDrawable(com.android.internal.R.drawable.quickcontact_badge);

        final int width = r.getDimensionPixelSize(R.dimen.contact_shortcut_frame_width);
        final int height = r.getDimensionPixelSize(R.dimen.contact_shortcut_frame_height);

        frame.setBounds(0, 0, width, height);

        final Rect padding = new Rect();
        frame.getPadding(padding);

        final Rect source = new Rect(0, 0, photo.getWidth(), photo.getHeight());
        final Rect destination = new Rect(padding.left, padding.top,
                width - padding.right, height - padding.bottom);

        final int d = Math.max(width, height);
        final Bitmap b = Bitmap.createBitmap(d, d, Bitmap.Config.ARGB_8888);
        final Canvas c = new Canvas(b);

        c.translate((d - width) / 2.0f, (d - height) / 2.0f);
        frame.draw(c);
        c.drawBitmap(photo, source, destination, new Paint(Paint.FILTER_BITMAP_FLAG));

        return b;
    }

FileNameMap getContentTypeFor returns null Android

I have been using this piece of code for a long time to get the mime type of the file 

FileNameMap fileNameMap = URLConnection.getFileNameMap();
String type = fileNameMap.getContentTypeFor(fileName);

Today, I found out that sometimes it returns null and throws an null error exception. Since there is no other option I had to come up with a class.

import java.io.File;
import java.net.URLConnection;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
public class MimeTypes {
    private static final Map<String, String> EXT2MIME = new HashMap<String, String>();
    private static final Map<String, String> MIME2EXT = new HashMap<String, String>();
    private MimeTypes() {
    }
    static {
        // extension to MIME type
        EXT2MIME.put("", "application/octet-stream");
        EXT2MIME.put("ai", "application/postscript");
        EXT2MIME.put("aif", "audio/x-aiff");
        EXT2MIME.put("aifc", "audio/x-aiff");
        EXT2MIME.put("aiff", "audio/x-aiff");
        EXT2MIME.put("asf", "video/x-ms-asf");
        EXT2MIME.put("asr", "video/x-ms-asf");
        EXT2MIME.put("asx", "video/x-ms-asf");
        EXT2MIME.put("au", "audio/basic");
        EXT2MIME.put("avi", "video/x-msvideo");
        EXT2MIME.put("axs", "application/olescript");
        EXT2MIME.put("bas", "text/plain");
        EXT2MIME.put("bmp", "image/bmp");
        EXT2MIME.put("c", "text/plain");
        EXT2MIME.put("cat", "application/vnd.ms-pkiseccat");
        EXT2MIME.put("cdf", "application/x-cdf");
        EXT2MIME.put("cer", "application/x-x509-ca-cert");
        EXT2MIME.put("class", "application/java-vm");
        EXT2MIME.put("clp", "application/x-msclip");
        EXT2MIME.put("cmx", "image/x-cmx");
        EXT2MIME.put("cod", "image/cis-cod");
        EXT2MIME.put("cpio", "application/x-cpio");
        EXT2MIME.put("crd", "application/x-mscardfile");
        EXT2MIME.put("crl", "application/pkix-crl");
        EXT2MIME.put("crt", "application/x-x509-ca-cert");
        EXT2MIME.put("csh", "application/x-csh");
        EXT2MIME.put("css", "text/css");
        EXT2MIME.put("dll", "application/x-msdownload");
        EXT2MIME.put("doc", "application/msword");
        EXT2MIME.put("docx", "application/vnd.openxmlformats-officedocument.wordprocessingml.document");
        EXT2MIME.put("doct", "application/vnd.openxmlformats-officedocument.wordprocessingml.template");
        EXT2MIME.put("dot", "application/msword");
        EXT2MIME.put("dvi", "application/x-dvi");
        EXT2MIME.put("dxr", "application/x-director");
        EXT2MIME.put("eps", "application/postscript");
        EXT2MIME.put("epub", "application/epub+zip");
        EXT2MIME.put("etx", "text/x-setext");
        EXT2MIME.put("evy", "application/envoy");
        EXT2MIME.put("flac", "audio/flac");
        EXT2MIME.put("fif", "application/fractals");
        EXT2MIME.put("flr", "x-world/x-vrml");
        EXT2MIME.put("gif", "image/gif");
        EXT2MIME.put("gtar", "application/x-gtar");
        EXT2MIME.put("gz", "application/x-gzip");
        EXT2MIME.put("h", "text/plain");
        EXT2MIME.put("hdf", "application/x-hdf");
        EXT2MIME.put("hlp", "application/winhlp");
        EXT2MIME.put("hqx", "application/mac-binhex40");
        EXT2MIME.put("hta", "application/hta");
        EXT2MIME.put("htc", "text/x-component");
        EXT2MIME.put("htm", "text/html");
        EXT2MIME.put("html", "text/html");
        EXT2MIME.put("htt", "text/webviewhtml");
        EXT2MIME.put("ico", "image/x-icon");
        EXT2MIME.put("ief", "image/ief");
        EXT2MIME.put("iii", "application/x-iphone");
        EXT2MIME.put("isp", "application/x-internet-signup");
        EXT2MIME.put("jar", "application/java-archive");
        EXT2MIME.put("jfif", "image/pipeg");
        EXT2MIME.put("jpe", "image/jpeg");
        EXT2MIME.put("jpeg", "image/jpeg");
        EXT2MIME.put("jpg", "image/jpeg");
        EXT2MIME.put("js", "application/x-javascript");
        EXT2MIME.put("json", "application/json");
        EXT2MIME.put("latex", "application/x-latex");
        EXT2MIME.put("lsf", "video/x-la-asf");
        EXT2MIME.put("lsx", "video/x-la-asf");
        EXT2MIME.put("m3u", "audio/x-mpegurl");
        EXT2MIME.put("man", "application/x-troff-man");
        EXT2MIME.put("mdb", "application/x-msaccess");
        EXT2MIME.put("me", "application/x-troff-me");
        EXT2MIME.put("mhtv", "message/rfc822");
        EXT2MIME.put("mhtml", "message/rfc822");
        EXT2MIME.put("mid", "audio/mid");
        EXT2MIME.put("mov", "video/quicktime");
        EXT2MIME.put("movie", "video/x-sgi-movie");
        EXT2MIME.put("mp2", "video/mpeg");
        EXT2MIME.put("mp3", "audio/mpeg");
        EXT2MIME.put("mpa", "video/mpeg");
        EXT2MIME.put("mpe", "video/mpegv");
        EXT2MIME.put("mpeg", "video/mpeg");
        EXT2MIME.put("mpg", "video/mpegv");
        EXT2MIME.put("mpp", "application/vnd.ms-project");
        EXT2MIME.put("mpv2", "video/mpeg");
        EXT2MIME.put("ms", "application/x-troff-ms");
        EXT2MIME.put("mvb", "application/x-msmediaview");
        EXT2MIME.put("nws", "message/rfc822");
        EXT2MIME.put("oda", "application/oda");
        EXT2MIME.put("odb", "application/vnd.oasis.opendocument.database");
        EXT2MIME.put("odc", "application/vnd.oasis.opendocument.chart");
        EXT2MIME.put("odf", "application/vnd.oasis.opendocument.formula");
        EXT2MIME.put("odft", "application/vnd.oasis.opendocument.formula-template");
        EXT2MIME.put("odg", "application/vnd.oasis.opendocument.graphics");
        EXT2MIME.put("odi", "application/vnd.oasis.opendocument.image");
        EXT2MIME.put("odm", "application/vnd.oasis.opendocument.text-master");
        EXT2MIME.put("odp", "application/vnd.oasis.opendocument.presentation");
        EXT2MIME.put("ods", "application/vnd.oasis.opendocument.spreadsheet");
        EXT2MIME.put("odt", "application/vnd.oasis.opendocument.text");
        EXT2MIME.put("ogg", "audio/ogg");
        EXT2MIME.put("ogv", "video/ogg");
        EXT2MIME.put("otc", "application/vnd.oasis.opendocument.chart-template");
        EXT2MIME.put("otg", "application/vnd.oasis.opendocument.graphics-template");
        EXT2MIME.put("oth", "application/vnd.oasis.opendocument.text-web");
        EXT2MIME.put("oti", "application/vnd.oasis.opendocument.image-template");
        EXT2MIME.put("otp", "application/vnd.oasis.opendocument.presentation-template");
        EXT2MIME.put("ots", "application/vnd.oasis.opendocument.spreadsheet-template");
        EXT2MIME.put("ott", "application/vnd.oasis.opendocument.text-template");
        EXT2MIME.put("p10", "application/pkcs10");
        EXT2MIME.put("p12", "application/x-pkcs12v");
        EXT2MIME.put("p7b", "application/x-pkcs7-certificates");
        EXT2MIME.put("p7c", "application/x-pkcs7-mime");
        EXT2MIME.put("p7m", "application/x-pkcs7-mime");
        EXT2MIME.put("p7r", "application/x-pkcs7-certreqresp");
        EXT2MIME.put("p7s", "application/x-pkcs7-signature");
        EXT2MIME.put("pbm", "image/x-portable-bitmap");
        EXT2MIME.put("pdf", "application/pdf");
        EXT2MIME.put("pfx", "application/x-pkcs12");
        EXT2MIME.put("pgm", "image/x-portable-graymap");
        EXT2MIME.put("vpko", "application/ynd.ms-pkipko");
        EXT2MIME.put("pma", "application/x-perfmon");
        EXT2MIME.put("pmc", "application/x-perfmon");
        EXT2MIME.put("pml", "application/x-perfmon");
        EXT2MIME.put("pmr", "application/x-perfmon");
        EXT2MIME.put("pmw", "application/x-perfmon");
        EXT2MIME.put("png", "image/png");
        EXT2MIME.put("pnm", "image/x-portable-anymap");
        EXT2MIME.put("pot", "application/vnd.ms-powerpoint");
        EXT2MIME.put("ppm", "image/x-portable-pixmap");
        EXT2MIME.put("pps", "application/vnd.ms-powerpoint");
        EXT2MIME.put("ppt", "application/vnd.ms-powerpoint");
        EXT2MIME.put("pptx", "application/vnd.openxmlformats-officedocument.presentationml.presentation");
        EXT2MIME.put("ppsx", "application/vnd.openxmlformats-officedocument.presentationml.slideshow");
        EXT2MIME.put("potx", "application/vnd.openxmlformats-officedocument.presentationml.template");
        EXT2MIME.put("prf", "application/pics-rules");
        EXT2MIME.put("ps", "application/postscript");
        EXT2MIME.put("pub", "application/x-mspublisher");
        EXT2MIME.put("qt", "video/quicktime");
        EXT2MIME.put("ra", "audio/x-pn-realaudio");
        EXT2MIME.put("ram", "audio/x-pn-realaudio");
        EXT2MIME.put("ras", "image/x-cmu-raster");
        EXT2MIME.put("rgb", "image/x-rgb");
        EXT2MIME.put("rmi", "audio/mid");
        EXT2MIME.put("roff", "application/x-troff");
        EXT2MIME.put("rtf", "application/rtf");
        EXT2MIME.put("rtx", "text/richtext");
        EXT2MIME.put("ser", "application/java-serialized-object");
        EXT2MIME.put("scd", "application/x-msschedule");
        EXT2MIME.put("sct", "text/scriptlet");
        EXT2MIME.put("sh", "application/x-sh");
        EXT2MIME.put("shar", "application/x-shar");
        EXT2MIME.put("sit", "application/x-stuffit");
        EXT2MIME.put("snd", "audio/basic");
        EXT2MIME.put("spc", "application/x-pkcs7-certificates");
        EXT2MIME.put("spl", "application/futuresplash");
        EXT2MIME.put("src", "application/x-wais-source");
        EXT2MIME.put("sst", "application/vnd.ms-pkicertstore");
        EXT2MIME.put("stl", "application/vnd.ms-pkistl");
        EXT2MIME.put("stm", "text/html");
        EXT2MIME.put("svg", "image/svg+xml");
        EXT2MIME.put("swf", "application/x-shockwave-flash");
        EXT2MIME.put("t", "application/x-troff");
        EXT2MIME.put("tar", "application/x-tar");
        EXT2MIME.put("tcl", "application/x-tcl");
        EXT2MIME.put("tex", "application/x-tex");
        EXT2MIME.put("texi", "application/x-texinfo");
        EXT2MIME.put("texinfo", "application/x-texinfo");
        EXT2MIME.put("tgz", "application/x-compressed");
        EXT2MIME.put("tif", "image/tiff");
        EXT2MIME.put("tiff", "image/tiff");
        EXT2MIME.put("tr", "application/x-troff");
        EXT2MIME.put("trm", "application/x-msterminal");
        EXT2MIME.put("tsv", "text/tab-separated-values");
        EXT2MIME.put("txt", "text/plain");
        EXT2MIME.put("uls", "text/iuls");
        EXT2MIME.put("ustar", "application/x-ustar");
        EXT2MIME.put("vcf", "text/x-vcard");
        EXT2MIME.put("vrml", "x-world/x-vrml");
        EXT2MIME.put("wav", "audio/x-wav");
        EXT2MIME.put("wcm", "application/vnd.ms-works");
        EXT2MIME.put("wdb", "application/vnd.ms-works");
        EXT2MIME.put("wmf", "application/x-msmetafile");
        EXT2MIME.put("wps", "application/vnd.ms-works");
        EXT2MIME.put("wri", "application/x-mswrite");
        EXT2MIME.put("wrl", "x-world/x-vrml");
        EXT2MIME.put("wrz", "x-world/x-vrml");
        EXT2MIME.put("xaf", "x-world/x-vrml");
        EXT2MIME.put("xbm", "image/x-xbitmap");
        EXT2MIME.put("xla", "application/vnd.ms-excel");
        EXT2MIME.put("xlc", "application/vnd.ms-excel");
        EXT2MIME.put("xlm", "application/vnd.ms-excel");
        EXT2MIME.put("xls", "application/vnd.ms-excel");
        EXT2MIME.put("xlsx", "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet");
        EXT2MIME.put("xlt", "application/vnd.ms-excel");
        EXT2MIME.put("xltx", "application/vnd.openxmlformats-officedocument.spreadsheetml.template");
        EXT2MIME.put("xlw", "application/vnd.ms-excel");
        EXT2MIME.put("xml", "text/xml");
        EXT2MIME.put("xof", "x-world/x-vrml");
        EXT2MIME.put("xpm", "image/x-xpixmap");
        EXT2MIME.put("xwd", "image/x-xwindowdump");
        EXT2MIME.put("z", "application/x-compress");
        EXT2MIME.put("zip", "application/zip");
        // MIME type to extension
        MIME2EXT.put("application/octet-stream", "");
        MIME2EXT.put("application/envoy", "evy");
        MIME2EXT.put("application/epub+zip", "epub");
        MIME2EXT.put("application/fractals", "fif");
        MIME2EXT.put("application/futuresplash", "spl");
        MIME2EXT.put("application/hta", "hta");
        MIME2EXT.put("application/java-archive", "jar");
        MIME2EXT.put("application/java-serialized-object", "ser");
        MIME2EXT.put("application/java-vm", "class");
        MIME2EXT.put("application/javascript", "js");
        MIME2EXT.put("application/json", "json");
        MIME2EXT.put("application/mac-binhex40", "hqx");
        MIME2EXT.put("application/msword", "doc");
        MIME2EXT.put("application/oda", "oda");
        MIME2EXT.put("application/olescript", "axs");
        MIME2EXT.put("application/pdf", "pdf");
        MIME2EXT.put("application/pics-rules", "prf");
        MIME2EXT.put("application/pkcs10", "p10");
        MIME2EXT.put("application/pkix-crl", "crl");
        MIME2EXT.put("application/postscript", "ps");
        MIME2EXT.put("application/rtf", "rtf");
        MIME2EXT.put("application/vnd.ms-excel", "xls");
        MIME2EXT.put("application/vnd.ms-pkicertstore", "sst");
        MIME2EXT.put("application/vnd.ms-pkiseccat", "cat");
        MIME2EXT.put("application/vnd.ms-pkistl", "stl");
        MIME2EXT.put("application/vnd.ms-powerpoint", "ppt");
        MIME2EXT.put("application/vnd.ms-project", "mpp");
        MIME2EXT.put("application/vnd.ms-works", "wps");
        MIME2EXT.put("application/vnd.oasis.opendocument.chart", "odc");
        MIME2EXT.put("application/vnd.oasis.opendocument.chart-template", "otc");
        MIME2EXT.put("application/vnd.oasis.opendocument.database", "odb");
        MIME2EXT.put("application/vnd.oasis.opendocument.formula", "odf");
        MIME2EXT.put("application/vnd.oasis.opendocument.formula-template", "odft");
        MIME2EXT.put("application/vnd.oasis.opendocument.graphics", "odg");
        MIME2EXT.put("application/vnd.oasis.opendocument.graphics-template", "otg");
        MIME2EXT.put("application/vnd.oasis.opendocument.image", "odi");
        MIME2EXT.put("application/vnd.oasis.opendocument.image-template", "oti");
        MIME2EXT.put("application/vnd.oasis.opendocument.presentation", "odp");
        MIME2EXT.put("application/vnd.oasis.opendocument.presentation-template", "otp");
        MIME2EXT.put("application/vnd.oasis.opendocument.spreadsheet", "ods");
        MIME2EXT.put("application/vnd.oasis.opendocument.spreadsheet-template", "ots");
        MIME2EXT.put("application/vnd.oasis.opendocument.text", "odt");
        MIME2EXT.put("application/vnd.oasis.opendocument.text-master", "odm");
        MIME2EXT.put("application/vnd.oasis.opendocument.text-template", "ott");
        MIME2EXT.put("application/vnd.oasis.opendocument.text-web", "oth");
        MIME2EXT.put("application/vnd.openxmlformats-officedocument.presentationml.presentation", "pptx");
        MIME2EXT.put("application/vnd.openxmlformats-officedocument.presentationml.slideshow", "ppsx");
        MIME2EXT.put("application/vnd.openxmlformats-officedocument.presentationml.template", "potx");
        MIME2EXT.put("application/vnd.openxmlformats-officedocument.spreadsheetml.sheet", "xlsx");
        MIME2EXT.put("application/vnd.openxmlformats-officedocument.spreadsheetml.template", "xltx");
        MIME2EXT.put("application/winhlp", "hlp");
        MIME2EXT.put("application/x-cdf", "cdf");
        MIME2EXT.put("application/x-compress", "z");
        MIME2EXT.put("application/x-compressed", "tgz");
        MIME2EXT.put("application/x-cpio", "cpio");
        MIME2EXT.put("application/x-csh", "csh");
        MIME2EXT.put("application/x-director", "dxr");
        MIME2EXT.put("application/x-dvi", "dvi");
        MIME2EXT.put("application/x-gtar", "gtar");
        MIME2EXT.put("application/x-gzip", "gz");
        MIME2EXT.put("application/x-hdf", "hdf");
        MIME2EXT.put("application/x-internet-signup", "isp");
        MIME2EXT.put("application/x-iphone", "iii");
        MIME2EXT.put("application/x-javascript", "js");
        MIME2EXT.put("application/x-latex", "latex");
        MIME2EXT.put("application/x-msaccess", "mdb");
        MIME2EXT.put("application/x-mscardfile", "crd");
        MIME2EXT.put("application/x-msclip", "clp");
        MIME2EXT.put("application/x-msdownload", "dll");
        MIME2EXT.put("application/x-msmediaview", "mvb");
        MIME2EXT.put("application/x-msmetafile", "wmf");
        MIME2EXT.put("application/x-mspublisher", "pub");
        MIME2EXT.put("application/x-msschedule", "scd");
        MIME2EXT.put("application/x-msterminal", "trm");
        MIME2EXT.put("application/x-mswrite", "wri");
        MIME2EXT.put("application/x-perfmon", "pmw");
        MIME2EXT.put("application/x-pkcs12", "pfx");
        MIME2EXT.put("application/x-pkcs12v", "p12");
        MIME2EXT.put("application/x-pkcs7-certificates", "p7b");
        MIME2EXT.put("application/x-pkcs7-certificates", "spc");
        MIME2EXT.put("application/x-pkcs7-certreqresp", "p7r");
        MIME2EXT.put("application/x-pkcs7-mime", "p7m");
        MIME2EXT.put("application/x-pkcs7-signature", "p7s");
        MIME2EXT.put("application/x-sh", "sh");
        MIME2EXT.put("application/x-shar", "shar");
        MIME2EXT.put("application/x-shockwave-flash", "swf");
        MIME2EXT.put("application/x-stuffit", "sit");
        MIME2EXT.put("application/x-tar", "tar");
        MIME2EXT.put("application/x-tcl", "tcl");
        MIME2EXT.put("application/x-tex", "tex");
        MIME2EXT.put("application/x-texinfo", "texinfo");
        MIME2EXT.put("application/x-troff-man", "man");
        MIME2EXT.put("application/x-troff-me", "me");
        MIME2EXT.put("application/x-troff-ms", "ms");
        MIME2EXT.put("application/x-troff", "tr");
        MIME2EXT.put("application/x-ustar", "ustar");
        MIME2EXT.put("application/x-wais-source", "src");
        MIME2EXT.put("application/x-x509-ca-cert", "cer");
        MIME2EXT.put("application/ynd.ms-pkipko", "vpko");
        MIME2EXT.put("application/zip", "zip");
        MIME2EXT.put("audio/basic", "snd");
        MIME2EXT.put("audio/flac", "flac");
        MIME2EXT.put("audio/mid", "mid");
        MIME2EXT.put("audio/mpeg", "mp3");
        MIME2EXT.put("audio/ogg", "ogg");
        MIME2EXT.put("audio/x-aiff", "aif");
        MIME2EXT.put("audio/x-mpegurl", "m3u");
        MIME2EXT.put("audio/x-pn-realaudio", "ram");
        MIME2EXT.put("audio/x-wav", "wav");
        MIME2EXT.put("application/vnd.openxmlformats-officedocument.wordprocessingml.template", "doct");
        MIME2EXT.put("application/vnd.openxmlformats-officedocument.wordprocessingml.document", "docx");
        MIME2EXT.put("image/bmp", "bmp");
        MIME2EXT.put("image/cis-cod", "cod");
        MIME2EXT.put("image/gif", "gif");
        MIME2EXT.put("image/ief", "ief");
        MIME2EXT.put("image/jpeg", "jpeg");
        MIME2EXT.put("image/pipeg", "jfif");
        MIME2EXT.put("image/png", "png");
        MIME2EXT.put("image/svg+xml", "svg");
        MIME2EXT.put("image/tiff", "tiff");
        MIME2EXT.put("image/x-cmu-raster", "ras");
        MIME2EXT.put("image/x-cmx", "cmx");
        MIME2EXT.put("image/x-icon", "ico");
        MIME2EXT.put("image/x-portable-anymap", "pnm");
        MIME2EXT.put("image/x-portable-bitmap", "pbm");
        MIME2EXT.put("image/x-portable-graymap", "pgm");
        MIME2EXT.put("image/x-portable-pixmap", "ppm");
        MIME2EXT.put("image/x-rgb", "rgb");
        MIME2EXT.put("image/x-xbitmap", "xbm");
        MIME2EXT.put("image/x-xpixmap", "xpm");
        MIME2EXT.put("image/x-xwindowdump", "xwd");
        MIME2EXT.put("message/rfc822", "mhtml");
        MIME2EXT.put("text/css", "css");
        MIME2EXT.put("text/html", "html");
        MIME2EXT.put("text/iuls", "uls");
        MIME2EXT.put("text/plain", "txt");
        MIME2EXT.put("text/richtext", "rtx");
        MIME2EXT.put("text/scriptlet", "sct");
        MIME2EXT.put("text/tab-separated-values", "tsv");
        MIME2EXT.put("text/webviewhtml", "htt");
        MIME2EXT.put("text/x-component", "htc");
        MIME2EXT.put("text/x-setext", "etx");
        MIME2EXT.put("text/x-vcard", "vcf");
        MIME2EXT.put("text/xml", "xml");
        MIME2EXT.put("video/mpeg", "mpeg");
        MIME2EXT.put("video/mpegv", "mpe");
        MIME2EXT.put("video/ogg", "ogv");
        MIME2EXT.put("video/quicktime", "mov");
        MIME2EXT.put("video/quicktime", "qt");
        MIME2EXT.put("video/x-la-asf", "lsf");
        MIME2EXT.put("video/x-la-asf", "lsx");
        MIME2EXT.put("video/x-ms-asf", "asf");
        MIME2EXT.put("video/x-msvideo", "avi");
        MIME2EXT.put("video/x-sgi-movie", "movie");
        MIME2EXT.put("x-world/x-vrml", "vrml");
    }
    /**
     * Returns the MIME type for file extension.
     */
    public static String getMIMEType(String ext) {
        if (ext == null) {
            return EXT2MIME.get("");
        }
        int x = ext.lastIndexOf('.');
        if (x > -1) {
            ext = ext.substring(x + 1);
        }
        String mime = EXT2MIME.get(ext.toLowerCase());
        if (mime == null) {
            mime = URLConnection.getFileNameMap().getContentTypeFor("x." + ext);
        }
        if (mime == null) {
            mime = EXT2MIME.get("");
        }
        return mime;
    }
    /**
     * Returns the MIME type for a file.
     */
    public static String getMIMEType(File file) {
        if (file == null) {
            return getMIMEType("");
        }
        return getMIMEType(file.getName());
    }
    /**
     * Guesses a extension from a MIME type.
     */
    public static String getExtension(String mimeType) {
        if (mimeType == null) {
            return "";
        }
        int x = mimeType.indexOf(';');
        if (x > -1) {
            mimeType = mimeType.substring(0, x);
        }
        mimeType = mimeType.trim().toLowerCase(Locale.ENGLISH);
        String extension = MIME2EXT.get(mimeType);
        return ((extension == null || extension.length() == 0) ? "" : "." + extension);
    }
}