diff --git a/pom.xml b/pom.xml
index 3dcdaa12..9b8fd761 100644
--- a/pom.xml
+++ b/pom.xml
@@ -76,6 +76,8 @@
 				</includes>
 			</resource>
 		</resources>
+		<sourceDirectory>src/main/java</sourceDirectory>
+		<testSourceDirectory>test/main/java</testSourceDirectory>
 		<plugins>
 			<plugin>
 				<groupId>org.apache.maven.plugins</groupId>
@@ -589,13 +591,33 @@
 			<optional>true</optional>
 		</dependency>
 
-        <!-- String comparison library. Used for dynamic help system. -->
-        <dependency>
-            <groupId>net.ricecode</groupId>
-            <artifactId>string-similarity</artifactId>
-            <version>1.0.0</version>
+		<!-- Unit testing -->
+		<dependency>
+			<groupId>junit</groupId>
+			<artifactId>junit</artifactId>
+			<scope>test</scope>
+			<version>4.12</version>
+		</dependency>
+		<dependency>
+			<groupId>org.hamcrest</groupId>
+			<artifactId>java-hamcrest</artifactId>
+			<scope>test</scope>
+			<version>2.0.0.0</version>
+		</dependency>
+		<dependency>
+			<groupId>org.mockito</groupId>
+			<artifactId>mockito-core</artifactId>
+			<scope>test</scope>
+			<version>2.0.5-beta</version>
+		</dependency>
+
+		<!-- String comparison library. Used for dynamic help system. -->
+		<dependency>
+			<groupId>net.ricecode</groupId>
+			<artifactId>string-similarity</artifactId>
+			<version>1.0.0</version>
 			<scope>compile</scope>
 			<optional>true</optional>
-        </dependency>
+		</dependency>
 	</dependencies>
 </project>
diff --git a/src/main/java/fr/xephi/authme/Log4JFilter.java b/src/main/java/fr/xephi/authme/Log4JFilter.java
index dccaee6f..365b2cec 100644
--- a/src/main/java/fr/xephi/authme/Log4JFilter.java
+++ b/src/main/java/fr/xephi/authme/Log4JFilter.java
@@ -6,80 +6,50 @@ import org.apache.logging.log4j.core.LogEvent;
 import org.apache.logging.log4j.core.Logger;
 import org.apache.logging.log4j.message.Message;
 
+import fr.xephi.authme.util.StringUtils;
+
 /**
- *
+ * Implements a filter for Log4j to skip sensitive AuthMe commands.
  * @author Xephi59
  */
 public class Log4JFilter implements org.apache.logging.log4j.core.Filter {
+	
+    /** List of commands (lower-case) to skip. */
+    private static final String[] COMMANDS_TO_SKIP = { "/login ", "/l ", "/reg ", "/changepassword ",
+        "/unregister ", "/authme register ", "/authme changepassword ", "/authme reg ", "/authme cp ", 
+        "/register " };
 
+    /** Constructor. */
     public Log4JFilter() {
     }
 
     @Override
     public Result filter(LogEvent record) {
-        try {
-            if (record == null || record.getMessage() == null)
-                return Result.NEUTRAL;
-            String logM = record.getMessage().getFormattedMessage().toLowerCase();
-            if (!logM.contains("issued server command:"))
-                return Result.NEUTRAL;
-            if (!logM.contains("/login ") && !logM.contains("/l ") && !logM.contains("/reg ") && !logM.contains("/changepassword ") && !logM.contains("/unregister ") && !logM.contains("/authme register ") && !logM.contains("/authme changepassword ") && !logM.contains("/authme reg ") && !logM.contains("/authme cp ") && !logM.contains("/register "))
-                return Result.NEUTRAL;
-            return Result.DENY;
-        } catch (NullPointerException npe) {
-            return Result.NEUTRAL;
-        }
+    	if (record == null) {
+    		return Result.NEUTRAL;
+    	}
+    	return validateMessage(record.getMessage());
     }
 
     @Override
     public Result filter(Logger arg0, Level arg1, Marker arg2, String message,
             Object... arg4) {
-        try {
-            if (message == null)
-                return Result.NEUTRAL;
-            String logM = message.toLowerCase();
-            if (!logM.contains("issued server command:"))
-                return Result.NEUTRAL;
-            if (!logM.contains("/login ") && !logM.contains("/l ") && !logM.contains("/reg ") && !logM.contains("/changepassword ") && !logM.contains("/unregister ") && !logM.contains("/authme register ") && !logM.contains("/authme changepassword ") && !logM.contains("/authme reg ") && !logM.contains("/authme cp ") && !logM.contains("/register "))
-                return Result.NEUTRAL;
-            return Result.DENY;
-        } catch (NullPointerException npe) {
-            return Result.NEUTRAL;
-        }
+    	return validateMessage(message);
     }
 
     @Override
     public Result filter(Logger arg0, Level arg1, Marker arg2, Object message,
             Throwable arg4) {
-        try {
-            if (message == null)
-                return Result.NEUTRAL;
-            String logM = message.toString().toLowerCase();
-            if (!logM.contains("issued server command:"))
-                return Result.NEUTRAL;
-            if (!logM.contains("/login ") && !logM.contains("/l ") && !logM.contains("/reg ") && !logM.contains("/changepassword ") && !logM.contains("/unregister ") && !logM.contains("/authme register ") && !logM.contains("/authme changepassword ") && !logM.contains("/authme reg ") && !logM.contains("/authme cp ") && !logM.contains("/register "))
-                return Result.NEUTRAL;
-            return Result.DENY;
-        } catch (NullPointerException npe) {
-            return Result.NEUTRAL;
-        }
+    	if (message == null) {
+    		return Result.NEUTRAL;
+    	}
+    	return validateMessage(message.toString());
     }
 
     @Override
     public Result filter(Logger arg0, Level arg1, Marker arg2, Message message,
             Throwable arg4) {
-        try {
-            if (message == null)
-                return Result.NEUTRAL;
-            String logM = message.getFormattedMessage().toLowerCase();
-            if (!logM.contains("issued server command:"))
-                return Result.NEUTRAL;
-            if (!logM.contains("/login ") && !logM.contains("/l ") && !logM.contains("/reg ") && !logM.contains("/changepassword ") && !logM.contains("/unregister ") && !logM.contains("/authme register ") && !logM.contains("/authme changepassword ") && !logM.contains("/authme reg ") && !logM.contains("/authme cp ") && !logM.contains("/register "))
-                return Result.NEUTRAL;
-            return Result.DENY;
-        } catch (NullPointerException npe) {
-            return Result.NEUTRAL;
-        }
+    	return validateMessage(message);
     }
 
     @Override
@@ -92,4 +62,39 @@ public class Log4JFilter implements org.apache.logging.log4j.core.Filter {
         return Result.NEUTRAL;
     }
 
+	/**
+	 * Validates a Message instance and returns the {@link Result} value
+	 * depending depending on whether the message contains sensitive AuthMe
+	 * data.
+	 *
+	 * @param message the Message object to verify
+	 * @return the Result value
+	 */
+    private static Result validateMessage(Message message) {
+    	if (message == null) {
+    		return Result.NEUTRAL;
+    	}
+    	return validateMessage(message.getFormattedMessage());
+    }
+    
+	/**
+	 * Validates a message and returns the {@link Result} value depending
+	 * depending on whether the message contains sensitive AuthMe data.
+	 *
+	 * @param message the message to verify
+	 * @return the Result value
+	 */
+    private static Result validateMessage(String message) {
+    	if (message == null) {
+    		return Result.NEUTRAL;
+    	}
+    	
+    	String lowerMessage = message.toLowerCase();
+    	if (lowerMessage.contains("issued server command:") 
+    			&& StringUtils.containsAny(lowerMessage, COMMANDS_TO_SKIP)) {
+    		return Result.DENY;
+    	}
+    	return Result.NEUTRAL;
+    }
+
 }
diff --git a/src/main/java/fr/xephi/authme/util/StringUtils.java b/src/main/java/fr/xephi/authme/util/StringUtils.java
index eab7ea15..da6f91ba 100644
--- a/src/main/java/fr/xephi/authme/util/StringUtils.java
+++ b/src/main/java/fr/xephi/authme/util/StringUtils.java
@@ -25,4 +25,16 @@ public class StringUtils {
         // Determine the difference value, return the result
         return Math.abs(service.score(first, second) - 1.0);
     }
+    
+    public static boolean containsAny(String str, String... pieces) {
+    	if (str == null) {
+    		return false;
+    	}
+    	for (String piece : pieces) {
+    		if (str.contains(piece)) {
+    			return true;
+    		}
+    	}
+    	return false;
+    }
 }
diff --git a/test/main/java/fr/xephi/authme/Log4JFilterTest.java b/test/main/java/fr/xephi/authme/Log4JFilterTest.java
new file mode 100644
index 00000000..5614eb51
--- /dev/null
+++ b/test/main/java/fr/xephi/authme/Log4JFilterTest.java
@@ -0,0 +1,230 @@
+package fr.xephi.authme;
+
+import static org.hamcrest.Matchers.equalTo;
+import static org.junit.Assert.assertThat;
+import static org.mockito.Mockito.when;
+
+import org.apache.logging.log4j.core.Filter.Result;
+import org.apache.logging.log4j.core.LogEvent;
+import org.apache.logging.log4j.message.Message;
+import org.junit.Test;
+import org.mockito.Mockito;
+
+/**
+ * Test for {@link Log4JFilter}.
+ */
+public class Log4JFilterTest {
+	
+	private final Log4JFilter log4JFilter = new Log4JFilter();
+	
+	private static final String SENSITIVE_COMMAND = "User issued server command: /login pass pass";
+	private static final String NORMAL_COMMAND = "User issued server command: /help";
+	private static final String OTHER_COMMAND = "Starting the server... Write /l for logs";
+
+	// ---------
+	// Test the filter(LogEvent) method
+	// ---------
+	@Test
+	public void shouldFilterSensitiveLogEvent() {
+		// given
+		Message message = mockMessage(SENSITIVE_COMMAND);
+		LogEvent event = Mockito.mock(LogEvent.class);
+		when(event.getMessage()).thenReturn(message);
+		
+		// when
+		Result result = log4JFilter.filter(event);
+		
+		// then
+		assertThat(result, equalTo(Result.DENY));
+	}
+	
+	@Test
+	public void shouldNotFilterIrrelevantLogEvent() {
+		// given
+		Message message = mockMessage(NORMAL_COMMAND);
+		LogEvent event = Mockito.mock(LogEvent.class);
+		when(event.getMessage()).thenReturn(message);
+		
+		// when
+		Result result = log4JFilter.filter(event);
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldNotFilterNonCommandLogEvent() {
+		// given
+		Message message = mockMessage(OTHER_COMMAND);
+		LogEvent event = Mockito.mock(LogEvent.class);
+		when(event.getMessage()).thenReturn(message);
+		
+		// when
+		Result result = log4JFilter.filter(event);
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldNotFilterLogEventWithNullMessage() {
+		// given
+		Message message = mockMessage(null);
+		LogEvent event = Mockito.mock(LogEvent.class);
+		when(event.getMessage()).thenReturn(message);
+		
+		// when
+		Result result = log4JFilter.filter(event);
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldNotFilterWhenLogEventIsNull() {
+		// given / when
+		Result result = log4JFilter.filter(null);
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	// ----------
+	// Test filter(Logger, Level, Marker, String, Object...)
+	// ----------
+	@Test
+	public void shouldFilterSensitiveStringMessage() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, SENSITIVE_COMMAND, new Object[0]);
+		
+		// then
+		assertThat(result, equalTo(Result.DENY));
+	}
+	
+	@Test
+	public void shouldNotFilterNormalStringMessage() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, NORMAL_COMMAND, new Object[0]);
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldNotFilterNonCommandStringMessage() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, OTHER_COMMAND, new Object[0]);
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldReturnNeutralForNullMessage() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, null, new Object[0]);
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	// --------
+	// Test filter(Logger, Level, Marker, Object, Throwable)
+	// --------
+	@Test
+	public void shouldFilterSensitiveObjectMessage() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, SENSITIVE_COMMAND, new Exception());
+		
+		// then
+		assertThat(result, equalTo(Result.DENY));
+	}
+	
+	@Test
+	public void shouldNotFilterNullObjectParam() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, (Object) null, new Exception());
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldNotFilterIrrelevantMessage() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, OTHER_COMMAND, new Exception());
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldNotFilterNonSensitiveCommand() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, NORMAL_COMMAND, new Exception());
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	// --------
+	// Test filter(Logger, Level, Marker, Message, Throwable)
+	// --------
+	@Test
+	public void shouldFilterSensitiveMessage() {
+		// given
+		Message message = mockMessage(SENSITIVE_COMMAND);
+		
+		// when
+		Result result = log4JFilter.filter(null, null, null, message, new Exception());
+		
+		// then
+		assertThat(result, equalTo(Result.DENY));
+	}
+	
+	@Test
+	public void shouldNotFilterNonSensitiveMessage() {
+		// given
+		Message message = mockMessage(NORMAL_COMMAND);
+		
+		// when
+		Result result = log4JFilter.filter(null, null, null, message, new Exception());
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldNotFilterNonCommandMessage() {
+		// given
+		Message message = mockMessage(OTHER_COMMAND);
+		
+		// when
+		Result result = log4JFilter.filter(null, null, null, message, new Exception());
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	@Test
+	public void shouldNotFilterNullMessage() {
+		// given / when
+		Result result = log4JFilter.filter(null, null, null, (Message) null, new Exception());
+		
+		// then
+		assertThat(result, equalTo(Result.NEUTRAL));
+	}
+	
+	/**
+	 * Mocks a {@link Message} object and makes it return the given formatted message.
+	 *
+	 * @param formattedMessage the formatted message the mock should return
+	 * @return Message mock
+	 */
+	private static Message mockMessage(String formattedMessage) {
+		Message message = Mockito.mock(Message.class);
+		when(message.getFormattedMessage()).thenReturn(formattedMessage);
+		return message;
+	}
+
+}