From 2f7de7eebaeca17a10f7692b450ad8f2eaa620e7 Mon Sep 17 00:00:00 2001
From: Thomas Scheffler <github@yagee.de>
Date: Thu, 16 Jul 2026 18:01:49 +0200
Subject: [PATCH] MCR-3764 Warn about missing or deprecated classes in
 configuration

---
 .../common/events/MCRStartupHandler.java      | 75 +++++++++++++++++++
 .../main/resources/config/mycore.properties   |  3 +-
 2 files changed, 77 insertions(+), 1 deletion(-)

diff --git a/mycore-base/src/main/java/org/mycore/common/events/MCRStartupHandler.java b/mycore-base/src/main/java/org/mycore/common/events/MCRStartupHandler.java
index faaad89178..d20d3852f8 100644
--- a/mycore-base/src/main/java/org/mycore/common/events/MCRStartupHandler.java
+++ b/mycore-base/src/main/java/org/mycore/common/events/MCRStartupHandler.java
@@ -24,9 +24,15 @@
 import java.io.IOException;
 import java.time.ZoneId;
 import java.time.format.DateTimeFormatter;
+import java.util.Comparator;
 import java.util.List;
 import java.util.Locale;
+import java.util.Objects;
+import java.util.SortedSet;
+import java.util.TreeSet;
 import java.util.jar.JarFile;
+import java.util.regex.Pattern;
+import java.util.stream.Collectors;
 
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -82,6 +88,18 @@ public static void startUp(ServletContext servletContext) {
             LOGGER.info("Library order: {}", () -> servletContext.getAttribute(ORDERED_LIBS));
         }
 
+        if (MCRConfiguration2.getBoolean("MCR.Startup.CheckClassProperties").orElse(false)) {
+            SortedSet<PropertyClassStatus> propertyClassStatuses = checkClassProperties();
+            if (!propertyClassStatuses.isEmpty()) {
+                MCRTableMessage<PropertyClassStatus> propertyTable = new MCRTableMessage<>(
+                    new MCRTableMessage.Column<>("Property", PropertyClassStatus::property),
+                    new MCRTableMessage.Column<>("Class", PropertyClassStatus::className),
+                    new MCRTableMessage.Column<>("Status", PropertyClassStatus::status));
+                propertyClassStatuses.forEach(propertyTable::add);
+                LOGGER.warn(() -> propertyTable.logMessage("Configured Classes report:"));
+            }
+        }
+
         MCRTableMessage<AutoExecutable> executableTable = new MCRTableMessage<>(
             new MCRTableMessage.Column<>("Name", AutoExecutable::getName),
             new MCRTableMessage.Column<>("Priority", AutoExecutable::getPriority),
@@ -98,6 +116,34 @@ public static void startUp(ServletContext servletContext) {
 
     }
 
+    private static SortedSet<PropertyClassStatus> checkClassProperties() {
+        Pattern classPattern = Pattern.compile(MCRConfiguration2.getString("MCR.Startup.CheckClassRegEx").orElse("^$"));
+        return MCRConfiguration2.getPropertiesMap()
+            .entrySet()
+            .stream()
+            .filter(entry -> isClassProperty(entry.getKey(), entry.getValue(), classPattern))
+            .flatMap(entry -> MCRConfiguration2.splitValue(entry.getValue())
+                .map(value -> new PropertyClassStatus(entry.getKey(), value, null)))
+            .filter(pcs -> !pcs.className.isBlank())
+            .map(pcs -> {
+                try {
+                    Class<?> aClass = Class.forName(pcs.className(), false, MCRClassTools.getClassLoader());
+                    if (aClass.getAnnotation(Deprecated.class) != null) {
+                        return new PropertyClassStatus(pcs.property(), pcs.className(), ClassStatus.DEPRECATED);
+                    }
+                } catch (ClassNotFoundException | LinkageError e) {
+                    return new PropertyClassStatus(pcs.property(), pcs.className(), ClassStatus.NOT_FOUND);
+                }
+                return null;
+            })
+            .filter(Objects::nonNull)
+            .collect(Collectors.toCollection(TreeSet::new));
+    }
+
+    private static boolean isClassProperty(String key, String value, Pattern classPattern) {
+        return key.endsWith(".Class") || classPattern.matcher(value).find();
+    }
+
     private static String toType(MCRComponent component) {
         if (component.isMyCoReBaseComponent()) {
             return "MyCoRe base component";
@@ -168,4 +214,33 @@ default int compareTo(AutoExecutable other) {
         }
 
     }
+
+    private enum ClassStatus {
+        NOT_FOUND("not found"), DEPRECATED("deprecated");
+
+        private final String tableValue;
+
+        ClassStatus(String tableValue) {
+            this.tableValue = tableValue;
+        }
+
+        @Override
+        public String toString() {
+            return tableValue;
+        }
+    }
+
+    private record PropertyClassStatus(String property, String className, ClassStatus status)
+        implements Comparable<PropertyClassStatus> {
+
+        private static final Comparator<PropertyClassStatus> COMPARATOR =
+            Comparator.comparing(PropertyClassStatus::status)
+                .thenComparing(PropertyClassStatus::property)
+                .thenComparing(PropertyClassStatus::className);
+
+        @Override
+        public int compareTo(PropertyClassStatus other) {
+            return COMPARATOR.compare(this, other);
+        }
+    }
 }
diff --git a/mycore-base/src/main/resources/config/mycore.properties b/mycore-base/src/main/resources/config/mycore.properties
index 7d6d2a7f5e..7e414e84df 100644
--- a/mycore-base/src/main/resources/config/mycore.properties
+++ b/mycore-base/src/main/resources/config/mycore.properties
@@ -584,7 +584,8 @@ MCR.Jersey.Resource.ApplicationPaths=rsc
 ##############################################################################
 
 MCR.Startup.Class=org.mycore.backend.jpa.MCRJPAConfigurationCheck,org.mycore.backend.jpa.MCRJPABootstrapper,org.mycore.datamodel.niofs.MCRFileSystemPromoter,org.mycore.frontend.support.MCRAutoDeploy,org.mycore.frontend.fileupload.MCRUploadServletDeployer,org.mycore.frontend.jersey.MCRJWTUtil
-
+MCR.Startup.CheckClassProperties=true
+MCR.Startup.CheckClassRegEx=(?:^|,\\s*)org\\.mycore(\\.[a-z0-9]+)*\\.[A-Z]
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