Add ExtensionResolutionExceptionFacade for Maven 3.x/4.x compatibility

org.eclipse.m2e.core/src/org/eclipse/m2e/core/internal/embedder/PlexusContainerManager.java

@@ -49,7 +49,6 @@
 import org.codehaus.plexus.DefaultPlexusContainer;
 import org.codehaus.plexus.PlexusConstants;
 import org.codehaus.plexus.PlexusContainer;
-import org.codehaus.plexus.PlexusContainerException;
 import org.codehaus.plexus.classworlds.ClassWorld;
 import org.codehaus.plexus.classworlds.realm.ClassRealm;
 import org.codehaus.plexus.classworlds.realm.DuplicateRealmException;
@@ -71,6 +70,7 @@
 import org.eclipse.m2e.core.embedder.IComponentLookup;
 import org.eclipse.m2e.core.embedder.IMavenConfiguration;
 import org.eclipse.m2e.core.internal.Messages;
+import org.eclipse.m2e.internal.maven.compat.ExtensionResolutionExceptionFacade;
 
 
 /**
@@ -180,14 +180,8 @@ public IMavenPlexusContainer aquire(File basedir) throws Exception {
           containerMap.put(canonicalDirectory, plexusContainer);
         } catch(ExtensionResolutionException e) {
           //TODO how can we create an error marker on the extension file?
-          CoreExtension extension = e.getExtension();
           File file = new File(directory, IMavenPlexusContainer.EXTENSIONS_FILENAME);
-          throw new PlexusContainerException(
-              "can't create plexus container for basedir = " + basedir.getAbsolutePath() + " because the extension "
-                  + extension.getGroupId() + ":" + extension.getArtifactId() + ":" + extension.getVersion()
-                  + " can't be loaded (defined in "
-                  + file.getAbsolutePath() + ").",
-              e);
+          new ExtensionResolutionExceptionFacade(e).throwForFile(file);
         }
       }
       return plexusContainer;

org.eclipse.m2e.maven.runtime/src/main/java/org/eclipse/m2e/internal/maven/compat/ExtensionResolutionExceptionFacade.java

@@ -0,0 +1,52 @@
+/********************************************************************************
+ * Copyright (c) 2025 Christoph Läubrich and others
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-2.0.
+ *
+ * SPDX-License-Identifier: EPL-2.0
+ *
+ * Contributors:
+ *   Christoph Läubrich - initial API and implementation
+ ********************************************************************************/
+
+package org.eclipse.m2e.internal.maven.compat;
+
+import java.io.File;
+
+import org.apache.maven.cli.internal.ExtensionResolutionException;
+import org.apache.maven.cli.internal.extension.model.CoreExtension;
+import org.codehaus.plexus.PlexusContainerException;
+
+/**
+ * Facade for {@link ExtensionResolutionException} to avoid direct usage that might change in Maven 4.
+ * This facade wraps the exception and provides a method to throw it as a PlexusContainerException
+ * with appropriate context information.
+ */
+public class ExtensionResolutionExceptionFacade {
+
+  private final ExtensionResolutionException exception;
+
+  public ExtensionResolutionExceptionFacade(ExtensionResolutionException exception) {
+    if(exception == null) {
+      throw new IllegalArgumentException("exception cannot be null");
+    }
+    this.exception = exception;
+  }
+
+  /**
+   * Throws a PlexusContainerException with information about the failed extension and the file where it was defined.
+   * 
+   * @param file the extensions file where the failed extension was defined
+   * @throws PlexusContainerException always thrown with details about the failed extension
+   */
+  public void throwForFile(File file) throws PlexusContainerException {
+    CoreExtension extension = exception.getExtension();
+    throw new PlexusContainerException(
+        "can't create plexus container because the extension " + extension.getGroupId() + ":"
+            + extension.getArtifactId() + ":" + extension.getVersion() + " can't be loaded (defined in "
+            + file.getAbsolutePath() + ").",
+        exception);
+  }
+}