diff --git a/url-detector/src/main/java/com/linkedin/urls/detection/UrlDetector.java b/url-detector/src/main/java/com/linkedin/urls/detection/UrlDetector.java
index 43815f6..1b6bc10 100644
--- a/url-detector/src/main/java/com/linkedin/urls/detection/UrlDetector.java
+++ b/url-detector/src/main/java/com/linkedin/urls/detection/UrlDetector.java
@@ -154,7 +154,6 @@ private void readDefault() {
     while (!_reader.eof()) {
       //read the next char to process.
       char curr = _reader.read();
-
       switch (curr) {
         case ' ':
           //space was found, check if it's a valid single level domain.
@@ -277,10 +276,16 @@ private void readDefault() {
   private int processColon(int length) {
     if (_hasScheme) {
       //read it as username/password if it has scheme
-      if (!readUserPass(length) && _buffer.length() > 0) {
+      if (!readUserPass(length)) {
         //unread the ":" so that the domain reader can process it
         _reader.goBack();
-        _buffer.delete(_buffer.length() - 1, _buffer.length());
+        
+        // Check buffer length before clearing it; set length to 0 if buffer is empty
+        if (_buffer.length() > 0) {
+          _buffer.delete(_buffer.length() - 1, _buffer.length());
+        } else {
+          length = 0;
+        }
 
         int backtrackOnFail = _reader.getPosition() - _buffer.length() + length;
         if (!readDomainName(_buffer.substring(length))) {
@@ -289,6 +294,8 @@ private int processColon(int length) {
           readEnd(ReadEndState.InvalidUrl);
         }
         length = 0;
+      } else {
+    	length = 0;
       }
     } else if (readScheme() && _buffer.length() > 0) {
       _hasScheme = true;
@@ -470,10 +477,9 @@ private boolean readScheme() {
    * @return True if a valid username and password was found.
    */
   private boolean readUserPass(int beginningOfUsername) {
-
     //The start of where we are.
     int start = _buffer.length();
-
+    
     //keep looping until "done"
     boolean done = false;