From 7f75f47c29d5183be0881f49c5a017d7aef00a9e Mon Sep 17 00:00:00 2001
From: Lukas Eder <lukas.eder@gmail.com>
Date: Thu, 13 Jun 2019 12:20:16 +0200
Subject: [PATCH] [jOOQ/jOOQ#8781] Improve error msg when org.jooq.util class
 not found

Users keep running into issues when they don't see why their
org.jooq.util classes from the code generator cannot be found. This
change helps them better find the new package qualification of types in
the jOOQ-meta and jOOQ-codegen modules.
---
 .../java/org/jooq/codegen/GenerationTool.java | 32 ++++++++++++++-----
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/jOOQ-codegen/src/main/java/org/jooq/codegen/GenerationTool.java b/jOOQ-codegen/src/main/java/org/jooq/codegen/GenerationTool.java
index 5fc4e57a3f..bda73ae416 100644
--- a/jOOQ-codegen/src/main/java/org/jooq/codegen/GenerationTool.java
+++ b/jOOQ-codegen/src/main/java/org/jooq/codegen/GenerationTool.java
@@ -875,12 +875,7 @@ public class GenerationTool {
             // [#2283] If no explicit class loader was provided try loading the class
             // with "default" techniques
             if (loader == null) {
-                try {
-                    return Class.forName(className);
-                }
-                catch (ClassNotFoundException e) {
-                    return Thread.currentThread().getContextClassLoader().loadClass(className);
-                }
+                return loadClass0(className);
             }
 
             // Prefer the explicit class loader if available
@@ -892,10 +887,22 @@ public class GenerationTool {
         catch (ClassNotFoundException e) {
             String message = null;
 
-            // [#7556]
+            // [#7556] [#8781]
             if (className.startsWith("org.jooq.util.")) {
+                String alternative = null;
+
+                alternativeLoop:
+                for (String pkg : new String[] { "org.jooq.meta", "org.jooq.meta.extensions", "org.jooq.codegen", "org.jooq.codegen.maven" }) {
+                    try {
+                        alternative = loadClass0(className.replace("org.jooq.util", pkg)).getName();
+                        break alternativeLoop;
+                    }
+                    catch (ClassNotFoundException ignore) {}
+                }
+
                 log.warn("Type not found", message =
-                    "Your configured org.jooq.util type was not found.\n"
+                    "Your configured " + className + " type was not found.\n"
+                  + (alternative != null ? ("Did you mean " + alternative + "?\n") : "")
                   + "Do note that in jOOQ 3.11, jOOQ-meta and jOOQ-codegen packages have been renamed. New package names are:\n"
                   + "- org.jooq.meta\n"
                   + "- org.jooq.meta.extensions\n"
@@ -919,6 +926,15 @@ public class GenerationTool {
         }
     }
 
+    private Class<?> loadClass0(String className) throws ClassNotFoundException {
+        try {
+            return Class.forName(className);
+        }
+        catch (ClassNotFoundException e) {
+            return Thread.currentThread().getContextClassLoader().loadClass(className);
+        }
+    }
+
     private static String trim(String string) {
         return (string == null ? null : string.trim());
     }