Enable ability to disable logging of uncaught exceptions

You must pass your own exception handler in order to do this.

Implementors need to be sure to log if its not a desired throw or
otherwise you will have silent command failures.

core/src/main/java/co/aikar/commands/CommandManager.java

@@ -70,6 +70,7 @@ public abstract class CommandManager <
     protected final CommandReplacements replacements = new CommandReplacements(this);
     protected final CommandConditions<I, CEC, CC> conditions = new CommandConditions<>(this);
     protected ExceptionHandler defaultExceptionHandler = null;
+    boolean logUnhandledExceptions = true;
     protected Table<Class<?>, String, Object> dependencies = new Table<>();
     protected CommandHelpFormatter helpFormatter = new CommandHelpFormatter(this);
 
@@ -294,12 +295,35 @@ public abstract class CommandManager <
     /**
      * Sets the default {@link ExceptionHandler} that is called when an exception occurs while executing a command, if the command doesn't have it's own exception handler registered.
      *
-     * @param exceptionHandler the handler that should handle uncaught exceptions
+     * @param exceptionHandler the handler that should handle uncaught exceptions.  May not be null if logExceptions is false
      */
     public void setDefaultExceptionHandler(ExceptionHandler exceptionHandler) {
+        if (exceptionHandler == null && !this.logUnhandledExceptions) {
+            throw new IllegalArgumentException("You may not disable the default exception handler and have logging of unhandled exceptions disabled");
+        }
         defaultExceptionHandler = exceptionHandler;
     }
 
+    /**
+     * Sets the default {@link ExceptionHandler} that is called when an exception occurs while executing a command, if the command doesn't have it's own exception handler registered, and lets you control if ACF should also log the exception still.
+     * <p>
+     * If you disable logging, you need to log it yourself in your handler.
+     *
+     * @param exceptionHandler the handler that should handle uncaught exceptions. May not be null if logExceptions is false
+     * @param logExceptions    Whether or not to log exceptions.
+     */
+    public void setDefaultExceptionHandler(ExceptionHandler exceptionHandler, boolean logExceptions) {
+        if (exceptionHandler == null && !logExceptions) {
+            throw new IllegalArgumentException("You may not disable the default exception handler and have logging of unhandled exceptions disabled");
+        }
+        this.logUnhandledExceptions = logExceptions;
+        this.defaultExceptionHandler = exceptionHandler;
+    }
+
+    public boolean isLoggingUnhandledExceptions() {
+        return this.logUnhandledExceptions;
+    }
+
     /**
      * Gets the current default exception handler, might be null.
      *

core/src/main/java/co/aikar/commands/RegisteredCommand.java

@@ -179,7 +179,10 @@ public class RegisteredCommand <CEC extends CommandExecutionContext<CEC, ? exten
                 if (!this.manager.handleUncaughtException(scope, this, sender, args, e)) {
                     sender.sendMessage(MessageType.ERROR, MessageKeys.ERROR_PERFORMING_COMMAND);
                 }
-                this.manager.log(LogLevel.ERROR, "Exception in command: " + command + " " + ACFUtil.join(args), e);
+                boolean hasExceptionHandler = this.manager.defaultExceptionHandler != null || this.scope.getExceptionHandler() != null;
+                if (!hasExceptionHandler || this.manager.logUnhandledExceptions) {
+                    this.manager.log(LogLevel.ERROR, "Exception in command: " + command + " " + ACFUtil.join(args), e);
+                }
             } catch (Exception e2) {
                 this.manager.log(LogLevel.ERROR, "Exception in handleException for command: " + command + " " + ACFUtil.join(args), e);
                 this.manager.log(LogLevel.ERROR, "Exception triggered by exception handler:", e2);