Javadocs cleanup

src/main/java/com/gmail/nossr50/database/DatabaseManager.java

@@ -83,7 +83,7 @@ public interface DatabaseManager {
      * Convert all users from this database to the provided database using
      * {@link #saveUser(PlayerProfile)}.
      *
-     * @param the DatabaseManager to save to
+     * @param destination The DatabaseManager to save to
      */
     public void convertUsers(DatabaseManager destination);
 }

src/main/java/com/gmail/nossr50/database/DatabaseManagerFactory.java

@@ -33,7 +33,7 @@ public class DatabaseManagerFactory {
      * stable. This method is subject to change and/or removal in future
      * versions.
      *
-     * @param man the DatabaseManager class to use
+     * @param clazz the DatabaseManager class to use
      * @throws IllegalArgumentException if the provided class does not have
      *             an empty constructor
      */

src/main/java/com/gmail/nossr50/database/SQLDatabaseManager.java

@@ -912,7 +912,7 @@ public final class SQLDatabaseManager implements DatabaseManager {
     /**
      * Get the Integer. Only return first row / first field.
      *
-     * @param sql SQL query to execute
+     * @param statement SQL query to execute
      * @return the value in the first row / first field
      */
     private int readInt(PreparedStatement statement) {