Use spaces for indentation

src/main/java/me/goudham/listener/ClipboardEvent.java

@@ -3,6 +3,6 @@ package me.goudham.listener;
 import java.awt.Image;
 
 public interface ClipboardEvent {
-	void onCopyString(String stringContent);
-	void onCopyImage(Image imageContent);
+    void onCopyString(String stringContent);
+    void onCopyImage(Image imageContent);
 }