FileDocCategorySizeDatePackage
URLTransfer.javaAPI DocAzureus 3.0.3.411413Sun Aug 26 21:27:30 BST 2007org.gudy.azureus2.ui.swt

URLTransfer

public class URLTransfer extends org.eclipse.swt.dnd.ByteArrayTransfer
URL Transfer type for Drag and Drop of URLs Windows IDs are already functional. Please use Win32TransferTypes to determine the IDs for other OSes!
see
org.gudy.azureus2.ui.swt.test.Win32TransferTypes
author
Rene Leonhardt
author
TuxPaper (require incoming string types have an URL prefix)
author
TuxPaper (UTF-8, UTF-16, BOM stuff) TuxPaper's Notes: This class is flakey. It's better to use HTMLTransfer, and then parse the URL from the HTML. However, IE drag and drops do not support HTMLTransfer, so this class must stay Windows --- TypeIDs seem to be assigned differently on different platform versions (or maybe even different installations!). Here's some examples 49314: Moz/IE 0x01 4-0x00 0x80 lots-of-0x00 "[D]URL" lots-more-0x00 49315: Moz/IE Same as 49315, except unicode 49313: Moz/IE URL in .url format "[InternetShortcut]\nURL=%1" 49324: Moz/IE URL in text format 49395: Moz Same as 49324, except unicode 49319: Moz Dragged HTML Fragment with position information 49398: Moz Dragged HTML Fragment (NO position information, just HTML), unicode 49396: Moz HTML. Unknown. There's probably a link to the ID and they type name in the registry, or via a Windows API call. We don't want to do that, and fortunately, SWT doesn't seem to pay attention to getTypeIds() on Windows, so we check every typeid we get to see if we can parse an URL from it. Also, dragging from the IE URL bar hangs SWT (sometimes for a very long time). Fortunately, most people willdrag the URL from the actual content window. Dragging an IE bookmark is actually dragging the .url file, and should be handled by the FileTranfer (and then opening it and extracting the URL). Moz Bookmarks are processed as HTML. Linux --- For Linux, this class isn't required. HTMLTransfer will take care of Gecko and Konquerer. Opera --- As of 8.5, Opera still doesn't allow dragging outside of itself (at least on windows)

Fields Summary
private boolean
bCheckingString
We are in the process of checking a string to see if it's a valid URL
private static boolean
DEBUG
private static URLTransfer
_instance
private static final String[]
supportedTypes
private static final int[]
supportedTypeIds
Constructors Summary
Methods Summary
public org.gudy.azureus2.ui.swt.URLTransfer$URLTypebytebufferToJava(byte[] buffer)


		if (buffer == null) {
			if (DEBUG) System.out.println("buffer null");
			return null;
		}

		URLType myData = null;
		try {
			String data;
			if (buffer.length > 1) {
				if (DEBUG) {
					for (int i = 0; i < buffer.length; i++) {
						if (buffer[i] >= 32)
							System.out.print(((char) buffer[i]));
						else
							System.out.print("#");
					}
					System.out.println();
				}
				boolean bFirst0 = buffer[0] == 0;
				boolean bSecond0 = buffer[1] == 0;
				if (bFirst0 && bSecond0)
					// This is probably UTF-32 Big Endian.  
					// Let's hope default constructor can handle it (It can't)
					data = new String(buffer);
				else if (bFirst0)
					data = new String(buffer, "UTF-16BE");
				else if (bSecond0)
					data = new String(buffer, "UTF-16LE");
				else if (buffer[0] == (byte) 0xEF && buffer[1] == (byte) 0xBB
						&& buffer.length > 3 && buffer[2] == (byte) 0xBF)
					data = new String(buffer, 3, buffer.length - 3, "UTF-8");
				else if (buffer[0] == (byte) 0xFF || buffer[0] == (byte) 0xFE)
					data = new String(buffer, "UTF-16");
				else {
					data = new String(buffer);
				}
			} else {
				// Older Code:
				// Remove 0 values from byte array, messing up any Unicode strings 
				byte[] text = new byte[buffer.length];
				int j = 0;
				for (int i = 0; i < buffer.length; i++) {
					if (buffer[i] != 0)
						text[j++] = buffer[i];
				}

				data = new String(text, 0, j);
			}

			if (data == null) {
				if (DEBUG) System.out.println("data null");
				return null;
			}

			int iPos = data.indexOf("\nURL=");
			if (iPos > 0) {
				int iEndPos = data.indexOf("\r", iPos);
				if (iEndPos < 0) {
					iEndPos = data.length();
				}
				myData = new URLType();
				myData.linkURL = data.substring(iPos + 5, iEndPos);
				myData.linkText = "";
			} else {
				String[] split = data.split("[\r\n]+", 2);

				myData = new URLType();
				myData.linkURL = (split.length > 0) ? split[0] : "";
				myData.linkText = (split.length > 1) ? split[1] : "";
			}
		} catch (Exception ex) {
			ex.printStackTrace();
		}

		return myData;
public static org.gudy.azureus2.ui.swt.URLTransfergetInstance()

 

      
		return _instance;
protected int[]getTypeIds()

		return supportedTypeIds;
protected java.lang.String[]getTypeNames()

		return supportedTypes;
public booleanisSupportedType(org.eclipse.swt.dnd.TransferData transferData)

param
transferData
see
org.eclipse.swt.dnd.Transfer#isSupportedType(org.eclipse.swt.dnd.TransferData)
return

		if (bCheckingString)
			return true;

		if (transferData == null)
			return false;

		// TODO: Check if it's a string list of URLs

		// String -- Check if URL, skip to next if not
		URLType url = null;

		if (DEBUG) System.out.println("Checking if type #" + transferData.type + " is URL");

		bCheckingString = true;
		try {
			byte[] buffer = (byte[]) super.nativeToJava(transferData);
			url = bytebufferToJava(buffer);
		} catch (Exception e) {
			Debug.out(e);
		} finally {
			bCheckingString = false;
		}

		if (url == null) {
			if (DEBUG) System.out.println("no, Null URL for type #" + transferData.type);
			return false;
		}

		if (UrlUtils.isURL(url.linkURL, false)) {
			if (DEBUG) System.out.println("Yes, " + url.linkURL + " of type #" + transferData.type);
			return true;
		}

		if (DEBUG) System.out.println("no, " + url.linkURL + " not URL for type #" + transferData.type);
		return false;
public voidjavaToNative(java.lang.Object object, org.eclipse.swt.dnd.TransferData transferData)

		if (DEBUG)
			System.out.println("javaToNative called");

		if (object == null || !(object instanceof URLType[]))
			return;

		if (isSupportedType(transferData)) {
			URLType[] myTypes = (URLType[]) object;
			try {
				// write data to a byte array and then ask super to convert to pMedium
				ByteArrayOutputStream out = new ByteArrayOutputStream();
				DataOutputStream writeOut = new DataOutputStream(out);
				for (int i = 0, length = myTypes.length; i < length; i++) {
					writeOut.writeBytes(myTypes[i].linkURL);
					writeOut.writeBytes("\n");
					writeOut.writeBytes(myTypes[i].linkText);
				}
				byte[] buffer = out.toByteArray();
				writeOut.close();

				super.javaToNative(buffer, transferData);

			} catch (IOException e) {
			}
		}
public static voidmain(java.lang.String[] args)
Test for varioud UTF Strings BOM information from http://www.unicode.org/faq/utf_bom.html

param
args


		Map map = new LinkedHashMap();
		map.put("UTF-8", new byte[] { (byte) 0xEF, (byte) 0xbb, (byte) 0xbf, 'H",
				'i" });
		map.put("UTF-32 BE BOM", new byte[] { 0, 0, (byte) 0xFE, (byte) 0xFF, 'H",
				0, 0, 0, 'i", 0, 0, 0 });
		map.put("UTF-16 LE BOM", new byte[] { (byte) 0xFF, (byte) 0xFE, 'H", 0,
				'i", 0 });
		map.put("UTF-16 BE BOM", new byte[] { (byte) 0xFE, (byte) 0xFF, 0, 'H", 0,
				'i" });
		map.put("UTF-16 LE", new byte[] { 'H", 0, 'i", 0 });
		map.put("UTF-16 BE", new byte[] { 0, 'H", 0, 'i" });

		for (Iterator iterator = map.keySet().iterator(); iterator.hasNext();) {
			String element = (String) iterator.next();
			System.out.println(element + ":");
			byte[] buffer = (byte[]) map.get(element);

			boolean bFirst0 = buffer[0] == 0;
			boolean bSecond0 = buffer[1] == 0;
			String data = "";
			try {
				if (bFirst0 && bSecond0)
					// This is probably UTF-32 Big Endian.  
					// Let's hope default constructor can handle it (It can't)
					data = new String(buffer);
				else if (bFirst0)
					data = new String(buffer, "UTF-16BE");
				else if (bSecond0)
					data = new String(buffer, "UTF-16LE");
				else if (buffer[0] == (byte) 0xEF && buffer[1] == (byte) 0xBB
						&& buffer.length > 3 && buffer[2] == (byte) 0xBF)
					data = new String(buffer, 3, buffer.length - 3, "UTF-8");
				else if (buffer[0] == (byte) 0xFF || buffer[0] == (byte) 0xFE)
					data = new String(buffer, "UTF-16");
				else {
					data = new String(buffer);
				}
			} catch (UnsupportedEncodingException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

			System.out.println(data);
		}
public java.lang.ObjectnativeToJava(org.eclipse.swt.dnd.TransferData transferData)

		if (DEBUG) System.out.println("nativeToJava called");
		try {
			if (isSupportedType(transferData)) {
				byte [] buffer = (byte[]) super.nativeToJava(transferData);
				return bytebufferToJava(buffer);
			}
		} catch (Exception e) {
			Debug.out(e);
		}

		return null;
public static org.eclipse.swt.dnd.TransferDatapickBestType(org.eclipse.swt.dnd.TransferData[] dataTypes, org.eclipse.swt.dnd.TransferData def)
Sometimes, CF_Text will be in currentDataType even though CF_UNICODETEXT is present. This is a workaround until its fixed properly.

Place it in dropAccept 

if (event.data instanceof URLTransfer.URLType)
event.currentDataType = URLTransfer.pickBestType(event.dataTypes, event.currentDataType);

param
dataTypes
param
def
return

		for (int i = 0; i < supportedTypeIds.length; i++) {
			int supportedTypeID = supportedTypeIds[i];
			for (int j = 0; j < dataTypes.length; j++) {
				try {
  				TransferData data = dataTypes[j];
  				if (supportedTypeID == data.type)
  					return data;
				} catch (Throwable t) {
					Debug.out("Picking Best Type", t);
				}
			}
		}
		return def;