PVQ-4362 External actions - If an external action fails, log the error with the corresponding error code (add errors into config.json)

- reworked where exit codes are places
- added definition of error codes and messages to config.json (Desktop can parse this dictionary and use it for user friendly error messaging)

Author: peterkral-pdfix

config.json

@@ -142,7 +142,10 @@
                     "type": "file_path",
                     "value": ""
                 }
-            ]
+            ],
+            "errors": {
+                "101": "Unforseen error happened. More info in logs."
+            }
         }
     ]
 }

src/main/java/net/pdfix/App.java

@@ -16,11 +16,6 @@ public class App {
   private static String VERSION = "1.0.0";
   private static String APP_NAME = "Validate PDF Accessibility";
 
-  // Success codes: 0-100 for object counts
-  // Error codes: 101+ to avoid conflict with object counts
-  private static final int MAX_EXIT_CODE = 100; 
-  private static final int ERROR_GENERAL = 101;
-
   private static void displayVersion() {
     Properties properties = new Properties();
     try {
@@ -174,10 +169,11 @@ public int compare(File f1, File f2) {
         System.out.println("===============================================================================\n");
       }
       System.out.println("Process complete");
-      System.exit(Math.min(count, MAX_EXIT_CODE));
+      System.exit(Math.min(count, ExitCodes.MAX_SUCCESS));
     } catch (Exception e) {
+      System.err.println(ExitCodes.GENERAL_MESSAGE);
       System.err.println(e.getLocalizedMessage());
-      System.exit(ERROR_GENERAL);
+      System.exit(ExitCodes.GENERAL_ERROR);
     }
   }
 }

src/main/java/net/pdfix/ExitCodes.java

@@ -0,0 +1,13 @@
+/**
+ * Defines all system exit codes for the application.
+ */
+public class ExitCodes {
+    /** Biggest code for successful execution. Exit code 0-100 represents number of duplicate MCIDs. */
+    public static final int MAX_SUCCESS = 100;
+
+    /** Uncaught General error. Out of 0-100 range. */
+    public static final int GENERAL_ERROR = 101;
+
+    /** General error message for console. */
+    public static final String GENERAL_MESSAGE = "Unforseen error happened. More info in logs.";
+}