FileTransfer reworked (first steps - functionality as is), HttpUpload

separated, some bugfixes
- HttpUpload moved into own package
- FileTransfer managed by a central manager class, several
  FileTransferService implementation can be used
  - Security initializations moved to ConversationsPlusApplication
  - Access to PowerManager moved to ConversationsPlusApplication
  - Removed unused code fragments
  - Access to HttpConnectionManager is now static

14 files changed, 346 insertions, 17 deletions

diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/AbstractIqPacketParser.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/AbstractIqPacketParser.java
new file mode 100644
index 00000000..d777cb64
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/AbstractIqPacketParser.java
@@ -0,0 +1,43 @@
+package de.thedevstack.conversationsplus.xmpp;
+
+import de.thedevstack.conversationsplus.xml.Element;
+import de.thedevstack.conversationsplus.xmpp.exceptions.MissingRequiredContentException;
+import de.thedevstack.conversationsplus.xmpp.exceptions.MissingRequiredElementException;
+
+/**
+ *
+ */
+public abstract class AbstractIqPacketParser {
+    protected static Element findRequiredChild(Element element, String elementName, String namespace) throws MissingRequiredElementException {
+        if (null == element) {
+            return null;
+        }
+        Element child = element.findChild(elementName, namespace);
+        if (child == null) {
+            throw new MissingRequiredElementException(elementName, namespace, element);
+        }
+        return child;
+    }
+
+    protected static String findRequiredChildContent(Element element, String elementName) throws MissingRequiredContentException {
+        if (null == element) {
+            return null;
+        }
+        String childContent = element.findChildContent(elementName);
+        if (null == childContent) {
+            throw new MissingRequiredContentException(elementName, element);
+        }
+        return childContent;
+    }
+
+    protected static String findRequiredChildContent(Element element, String elementName, String namespace) throws MissingRequiredContentException {
+        if (null == element) {
+            return null;
+        }
+        String childContent = element.findChildContent(elementName, namespace);
+        if (null == childContent) {
+            throw new MissingRequiredContentException(elementName, namespace, element);
+        }
+        return childContent;
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/XmppConnection.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/XmppConnection.java
index a89f308f..c5a8fe3b 100644
--- a/src/main/java/de/thedevstack/conversationsplus/xmpp/XmppConnection.java
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/XmppConnection.java
@@ -2,7 +2,6 @@ package de.thedevstack.conversationsplus.xmpp;
 
 import android.graphics.Bitmap;
 import android.graphics.BitmapFactory;
-import android.os.PowerManager;
 import android.os.PowerManager.WakeLock;
 import android.os.SystemClock;
 import android.security.KeyChain;
@@ -50,6 +49,7 @@ import javax.net.ssl.X509TrustManager;
 
 import de.duenndns.ssl.MemorizingTrustManager;
 import de.thedevstack.android.logcat.Logging;
+import de.thedevstack.conversationsplus.ConversationsPlusApplication;
 import de.thedevstack.conversationsplus.ConversationsPlusPreferences;
 import de.thedevstack.conversationsplus.dto.SrvRecord;
 import de.thedevstack.conversationsplus.Config;
@@ -199,8 +199,7 @@ public class XmppConnection implements Runnable {
 
 	public XmppConnection(final Account account, final XmppConnectionService service) {
 		this.account = account;
-		this.wakeLock = service.getPowerManager().newWakeLock(
-				PowerManager.PARTIAL_WAKE_LOCK, account.getJid().toBareJid().toString());
+		this.wakeLock = ConversationsPlusApplication.createPartialWakeLock(account.getJid().toBareJid().toString());
 		tagWriter = new TagWriter();
 		mXmppConnectionService = service;
 	}
@@ -382,14 +381,14 @@ public class XmppConnection implements Runnable {
 
 	private TlsFactoryVerifier getTlsFactoryVerifier() throws NoSuchAlgorithmException, KeyManagementException, IOException {
 		final SSLContext sc = SSLSocketHelper.getSSLContext();
-		MemorizingTrustManager trustManager = this.mXmppConnectionService.getMemorizingTrustManager();
+		MemorizingTrustManager trustManager = ConversationsPlusApplication.getMemorizingTrustManager();
 		KeyManager[] keyManager;
 		if (account.getPrivateKeyAlias() != null && account.getPassword().isEmpty()) {
 			keyManager = new KeyManager[]{mKeyManager};
 		} else {
 			keyManager = null;
 		}
-		sc.init(keyManager, new X509TrustManager[]{mInteractive ? trustManager : trustManager.getNonInteractive()}, mXmppConnectionService.getRNG());
+		sc.init(keyManager, new X509TrustManager[]{mInteractive ? trustManager : trustManager.getNonInteractive()}, ConversationsPlusApplication.getSecureRandom());
 		final SSLSocketFactory factory = sc.getSocketFactory();
 		final HostnameVerifier verifier;
 		if (mInteractive) {
@@ -737,13 +736,13 @@ public class XmppConnection implements Runnable {
 		final Element auth = new Element("auth");
 		auth.setAttribute("xmlns", "urn:ietf:params:xml:ns:xmpp-sasl");
 		if (mechanisms.contains("EXTERNAL") && account.getPrivateKeyAlias() != null) {
-			saslMechanism = new External(tagWriter, account, mXmppConnectionService.getRNG());
+			saslMechanism = new External(tagWriter, account, ConversationsPlusApplication.getSecureRandom());
 		} else if (mechanisms.contains("SCRAM-SHA-1")) {
-			saslMechanism = new ScramSha1(tagWriter, account, mXmppConnectionService.getRNG());
+			saslMechanism = new ScramSha1(tagWriter, account, ConversationsPlusApplication.getSecureRandom());
 		} else if (mechanisms.contains("PLAIN")) {
 			saslMechanism = new Plain(tagWriter, account);
 		} else if (mechanisms.contains("DIGEST-MD5")) {
-			saslMechanism = new DigestMd5(tagWriter, account, mXmppConnectionService.getRNG());
+			saslMechanism = new DigestMd5(tagWriter, account, ConversationsPlusApplication.getSecureRandom());
 		}
 		if (saslMechanism != null) {
 			final JSONObject keys = account.getKeys();
@@ -1171,7 +1170,7 @@ public class XmppConnection implements Runnable {
 	}
 
 	private String nextRandomId() {
-		return new BigInteger(50, mXmppConnectionService.getRNG()).toString(32);
+		return new BigInteger(50, ConversationsPlusApplication.getSecureRandom()).toString(32);
 	}
 
 	public String sendIqPacket(final IqPacket packet, final OnIqPacketReceived callback) {
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/MissingRequiredContentException.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/MissingRequiredContentException.java
new file mode 100644
index 00000000..8b21cb9c
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/MissingRequiredContentException.java
@@ -0,0 +1,26 @@
+package de.thedevstack.conversationsplus.xmpp.exceptions;
+
+import de.thedevstack.conversationsplus.xml.Element;
+
+/**
+ *
+ */
+public class MissingRequiredContentException extends XmppException {
+    private String elementName;
+    private String namespace;
+
+    public MissingRequiredContentException(String elementName, Element context) {
+        super(context);
+        this.elementName = elementName;
+    }
+
+    public MissingRequiredContentException(String elementName, String namespace, Element context) {
+        this(elementName, context);
+        this.namespace = namespace;
+    }
+
+    @Override
+    public String getMessage() {
+        return "Missing required element content " + ((namespace != null) ? namespace + ":" : "") + elementName + " in context " + getContext();
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/MissingRequiredElementException.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/MissingRequiredElementException.java
new file mode 100644
index 00000000..8c8162ef
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/MissingRequiredElementException.java
@@ -0,0 +1,26 @@
+package de.thedevstack.conversationsplus.xmpp.exceptions;
+
+import de.thedevstack.conversationsplus.xml.Element;
+
+/**
+ *
+ */
+public class MissingRequiredElementException extends XmppException {
+    private String elementName;
+    private String namespace;
+
+    public MissingRequiredElementException(String elementName, Element context) {
+        super(context);
+        this.elementName = elementName;
+    }
+
+    public MissingRequiredElementException(String elementName, String namespace, Element context) {
+        this(elementName, context);
+        this.namespace = namespace;
+    }
+
+    @Override
+    public String getMessage() {
+        return "Missing required element " + ((namespace != null) ? namespace + ":" : "") + elementName + " in context " + getContext();
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/UnexpectedIqPacketTypeException.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/UnexpectedIqPacketTypeException.java
new file mode 100644
index 00000000..333f5dca
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/UnexpectedIqPacketTypeException.java
@@ -0,0 +1,25 @@
+package de.thedevstack.conversationsplus.xmpp.exceptions;
+
+import java.util.Arrays;
+
+import de.thedevstack.conversationsplus.xml.Element;
+import de.thedevstack.conversationsplus.xmpp.stanzas.IqPacket;
+
+/**
+ *
+ */
+public class UnexpectedIqPacketTypeException extends XmppException {
+    private final IqPacket.TYPE current;
+    private final IqPacket.TYPE[] expected;
+
+    public UnexpectedIqPacketTypeException(Element context, IqPacket.TYPE current, IqPacket.TYPE... expected) {
+        super(context);
+        this.expected = expected;
+        this.current = current;
+    }
+
+    @Override
+    public String getMessage() {
+        return "Unexpected IQ packet type '" + this.current + "' retrieved. One of " + Arrays.toString(expected) + " was expected.";
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/XmppException.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/XmppException.java
new file mode 100644
index 00000000..8c692f5b
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/exceptions/XmppException.java
@@ -0,0 +1,56 @@
+package de.thedevstack.conversationsplus.xmpp.exceptions;
+
+import de.thedevstack.conversationsplus.xml.Element;
+
+/**
+ *
+ */
+public class XmppException extends Exception {
+    private Element context;
+    /**
+     * Constructs a new {@code Exception} that includes the current stack trace.
+     */
+    public XmppException() {
+    }
+
+    /**
+     * Constructs a new {@code Exception} that includes the current stack trace.
+     */
+    public XmppException(Element context) {
+        this.context = context;
+    }
+
+    /**
+     * Constructs a new {@code Exception} with the current stack trace and the
+     * specified cause.
+     *
+     * @param throwable the cause of this exception.
+     */
+    public XmppException(Throwable throwable) {
+        super(throwable);
+    }
+
+    /**
+     * Constructs a new {@code Exception} with the current stack trace and the
+     * specified cause.
+     *
+     * @param throwable the cause of this exception.
+     */
+    public XmppException(Element context, Throwable throwable) {
+        super(throwable);
+        this.context = context;
+    }
+
+    @Override
+    public String getMessage() {
+        if (null != context) {
+            return "Error in XMPP Element. XML element is: " + this.context.toString();
+        } else {
+            return super.getMessage();
+        }
+    }
+
+    public Element getContext() {
+        return context;
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUpload.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUpload.java
new file mode 100644
index 00000000..28cba280
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUpload.java
@@ -0,0 +1,9 @@
+package de.thedevstack.conversationsplus.xmpp.httpupload;
+
+/**
+ *
+ */
+public interface HttpUpload {
+    String NAMESPACE = "urn:xmpp:http:upload";
+    String DEFAULT_MIME_TYPE = "application/octet-stream";
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUploadRequestSlotPacketGenerator.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUploadRequestSlotPacketGenerator.java
new file mode 100644
index 00000000..59851417
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUploadRequestSlotPacketGenerator.java
@@ -0,0 +1,46 @@
+package de.thedevstack.conversationsplus.xmpp.httpupload;
+
+import de.thedevstack.conversationsplus.xmpp.jid.Jid;
+import de.thedevstack.conversationsplus.xmpp.stanzas.IqPacket;
+
+/**
+ * Generates the IQ Packets for requesting a http upload slot
+ * as defined in XEP-0363.
+ * @see <a href="http://xmpp.org/extensions/xep-0363.html">http://xmpp.org/extensions/xep-0363.html</a>
+ */
+public final class HttpUploadRequestSlotPacketGenerator {
+    /**
+     * Generates the IqPacket to request a http upload slot.
+     * The attributes from and id are not set in here - this is added while sending the packet.
+     * <pre>
+     * <iq from='romeo@montague.tld/garden'
+     *     id='step_03'
+     *     to='upload.montague.tld'
+     *     type='get'>
+     *   <request xmlns='urn:xmpp:http:upload'>
+     *     <filename>my_juliet.png</filename>
+     *     <size>23456</size>
+     *     <content-type>image/jpeg</content-type>
+     *   </request>
+     * </iq>
+     * </pre>
+     * @param host the jid of the host to request a slot from
+     * @param filename the filename of the file which will be transferred
+     * @param filesize the filesize of the file which will be transferred
+     * @param mime the mime type of the file which will be transferred - <code>optional</code> and therefore nullable
+     * @return the IqPacket
+     */
+    public static IqPacket generate(Jid host, String filename, long filesize, String mime) {
+        SlotRequestPacket packet = new SlotRequestPacket(filename, filesize);
+        packet.setTo(host);
+        packet.setMime((mime == null) ? HttpUpload.DEFAULT_MIME_TYPE : mime);
+        return packet;
+    }
+
+    /**
+     * Utility class - avoid instantiation
+     */
+    private HttpUploadRequestSlotPacketGenerator() {
+        // Helper class - avoid instantiation
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUploadSlot.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUploadSlot.java
new file mode 100644
index 00000000..14fe5103
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/HttpUploadSlot.java
@@ -0,0 +1,22 @@
+package de.thedevstack.conversationsplus.xmpp.httpupload;
+
+/**
+ *
+ */
+public class HttpUploadSlot {
+    private final String getUrl;
+    private final String putUrl;
+
+    public HttpUploadSlot(String getUrl, String putUrl) {
+        this.getUrl = getUrl;
+        this.putUrl = putUrl;
+    }
+
+    public String getGetUrl() {
+        return this.getUrl;
+    }
+
+    public String getPutUrl() {
+        return this.putUrl;
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/SlotPacketParser.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/SlotPacketParser.java
new file mode 100644
index 00000000..0630449a
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/SlotPacketParser.java
@@ -0,0 +1,27 @@
+package de.thedevstack.conversationsplus.xmpp.httpupload;
+
+import de.thedevstack.conversationsplus.xml.Element;
+import de.thedevstack.conversationsplus.xmpp.AbstractIqPacketParser;
+import de.thedevstack.conversationsplus.xmpp.exceptions.UnexpectedIqPacketTypeException;
+import de.thedevstack.conversationsplus.xmpp.exceptions.XmppException;
+import de.thedevstack.conversationsplus.xmpp.stanzas.IqPacket;
+
+/**
+ *
+ */
+public final class SlotPacketParser extends AbstractIqPacketParser {
+    public static HttpUploadSlot parseGetAndPutUrl(IqPacket packet) throws XmppException {
+        if (packet.getType() == IqPacket.TYPE.RESULT) {
+            Element slot = findRequiredChild(packet, "slot", HttpUpload.NAMESPACE);
+
+            String getUrl = findRequiredChildContent(slot, "get");
+            String putUrl = findRequiredChildContent(slot, "put");
+
+            return new HttpUploadSlot(getUrl, putUrl);
+        } else if (packet.getType() == IqPacket.TYPE.ERROR) {
+            throw new XmppException(); // Do proper handling of error cases
+        } else {
+            throw new UnexpectedIqPacketTypeException(packet, packet.getType(), IqPacket.TYPE.RESULT, IqPacket.TYPE.ERROR);
+        }
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/SlotRequestPacket.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/SlotRequestPacket.java
new file mode 100644
index 00000000..d470d2f5
--- /dev/null
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/httpupload/SlotRequestPacket.java
@@ -0,0 +1,53 @@
+package de.thedevstack.conversationsplus.xmpp.httpupload;
+
+import de.thedevstack.conversationsplus.xml.Element;
+import de.thedevstack.conversationsplus.xmpp.stanzas.IqPacket;
+
+/**
+ *
+ */
+public class SlotRequestPacket extends IqPacket {
+    public static final String ELEMENT_NAME = "request";
+    public static final String FILENAME_ELEMENT_NAME = "filename";
+    public static final String FILESIZE_ELEMENT_NAME = "size";
+    public static final String MIME_ELEMENT_NAME = "content-type";
+    private Element requestElement;
+    private String filename;
+    private long filesize;
+    private String mime;
+
+    private SlotRequestPacket() {
+        super(TYPE.GET);
+        this.requestElement = super.addChild(SlotRequestPacket.ELEMENT_NAME, HttpUpload.NAMESPACE);
+    }
+
+    public SlotRequestPacket(String filename, long filesize) {
+        this();
+        this.setFilename(filename);
+        this.setFilesize(filesize);
+    }
+
+    public void setFilename(String filename) {
+        if (null == filename || filename.isEmpty()) {
+            throw new IllegalArgumentException("filename must not be null or empty.");
+        }
+        this.filename = filename;
+        this.requestElement.addChild(FILENAME_ELEMENT_NAME).setContent(filename);
+    }
+
+    public void setFilesize(long filesize) {
+        if (0 >= filesize) {
+            throw new IllegalArgumentException("filesize must not be null or empty.");
+        }
+        this.filesize = filesize;
+        this.requestElement.addChild(FILESIZE_ELEMENT_NAME).setContent(String.valueOf(filesize));
+    }
+
+    public void setMime(String mime) {
+        if (null == mime || mime.isEmpty()) {
+            throw new IllegalArgumentException("mime type must not be null or empty.");
+        }
+        this.mime = mime;
+        this.requestElement.addChild(MIME_ELEMENT_NAME).setContent(mime);
+    }
+}
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnection.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnection.java
index 422bdff0..ca823926 100644
--- a/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnection.java
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnection.java
@@ -33,6 +33,7 @@ import de.thedevstack.conversationsplus.persistance.FileBackend;
 import de.thedevstack.conversationsplus.services.AbstractConnectionManager;
 import de.thedevstack.conversationsplus.services.XmppConnectionService;
 import de.thedevstack.conversationsplus.utils.FileUtils;
+import de.thedevstack.conversationsplus.utils.XmppConnectionServiceAccessor;
 import de.thedevstack.conversationsplus.xml.Element;
 import de.thedevstack.conversationsplus.xmpp.OnIqPacketReceived;
 import de.thedevstack.conversationsplus.xmpp.jid.Jid;
@@ -157,8 +158,7 @@ public class JingleConnection implements Transferable {
 
 	public JingleConnection(JingleConnectionManager mJingleConnectionManager) {
 		this.mJingleConnectionManager = mJingleConnectionManager;
-		this.mXmppConnectionService = mJingleConnectionManager
-				.getXmppConnectionService();
+		this.mXmppConnectionService = XmppConnectionServiceAccessor.xmppConnectionService;
 	}
 
 	public String getSessionId() {
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnectionManager.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnectionManager.java
index 2deb79c6..30ed9024 100644
--- a/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnectionManager.java
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleConnectionManager.java
@@ -31,10 +31,6 @@ public class JingleConnectionManager extends AbstractConnectionManager {
 	@SuppressLint("TrulyRandom")
 	private SecureRandom random = new SecureRandom();
 
-	public JingleConnectionManager(XmppConnectionService service) {
-		super(service);
-	}
-
 	public void deliverPacket(Account account, JinglePacket packet) {
 		if (packet.isAction("session-initiate")) {
 			JingleConnection connection = new JingleConnection(this);
diff --git a/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleSocks5Transport.java b/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleSocks5Transport.java
index 9ea268d5..6480251f 100644
--- a/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleSocks5Transport.java
+++ b/src/main/java/de/thedevstack/conversationsplus/xmpp/jingle/JingleSocks5Transport.java
@@ -14,6 +14,7 @@ import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 
 import de.thedevstack.android.logcat.Logging;
+import de.thedevstack.conversationsplus.ConversationsPlusApplication;
 import de.thedevstack.conversationsplus.utils.StreamUtil;
 import de.thedevstack.conversationsplus.Config;
 import de.thedevstack.conversationsplus.entities.DownloadableFile;
@@ -84,7 +85,7 @@ public class JingleSocks5Transport extends JingleTransport {
 			@Override
 			public void run() {
 				InputStream fileInputStream = null;
-				final PowerManager.WakeLock wakeLock = connection.getConnectionManager().createWakeLock("jingle_send_"+connection.getSessionId());
+				final PowerManager.WakeLock wakeLock = ConversationsPlusApplication.createPartialWakeLock("jingle_send_"+connection.getSessionId());
 				try {
 					wakeLock.acquire();
 					MessageDigest digest = MessageDigest.getInstance("SHA-1");
@@ -134,7 +135,7 @@ public class JingleSocks5Transport extends JingleTransport {
 			@Override
 			public void run() {
 				OutputStream fileOutputStream = null;
-				final PowerManager.WakeLock wakeLock = connection.getConnectionManager().createWakeLock("jingle_receive_"+connection.getSessionId());
+				final PowerManager.WakeLock wakeLock = ConversationsPlusApplication.createPartialWakeLock("jingle_receive_"+connection.getSessionId());
 				try {
 					wakeLock.acquire();
 					MessageDigest digest = MessageDigest.getInstance("SHA-1");