Do not depend on DefaultRepositorySystemSession directly

Currently FilterRepositorySystemSession assumes that we always have a
DefaultRepositorySystemSession but this changes with Maven 4.

To prevent immediate failure on Maven 4 this now override the getter
methods as well and only forward the setData/TransferListener if we have
a DefaultRepositorySystemSession.

Author: laeubi

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

@@ -14,6 +14,7 @@
 package org.eclipse.m2e.core.internal.embedder;
 
 import org.eclipse.aether.DefaultRepositorySystemSession;
+import org.eclipse.aether.RepositorySystemSession;
 import org.eclipse.aether.SessionData;
 import org.eclipse.aether.transfer.TransferListener;
 
@@ -27,9 +28,13 @@ class FilterRepositorySystemSession extends org.eclipse.aether.AbstractForwardin
 
   private final String updatePolicy;
 
-  private final DefaultRepositorySystemSession session;
+  private final RepositorySystemSession session;
 
-  public FilterRepositorySystemSession(DefaultRepositorySystemSession session, String updatePolicy) {
+  private TransferListener transferListener;
+
+  private SessionData data;
+
+  public FilterRepositorySystemSession(RepositorySystemSession session, String updatePolicy) {
     this.session = session;
     this.updatePolicy = updatePolicy;
   }
@@ -39,22 +44,56 @@ public String getUpdatePolicy() {
     return updatePolicy != null ? updatePolicy : super.getUpdatePolicy();
   }
 
+  @Override
+  public TransferListener getTransferListener() {
+    if(this.transferListener == null) {
+      return session.getTransferListener();
+    }
+    return transferListener;
+  }
+
+  @Override
+  public SessionData getData() {
+    if(this.data == null) {
+      return session.getData();
+    }
+    return this.data;
+  }
+
   public TransferListener setTransferListener(TransferListener transferListener) {
-    DefaultRepositorySystemSession session = getSession();
-    TransferListener origTransferListener = session.getTransferListener();
-    session.setTransferListener(transferListener);
+    TransferListener origTransferListener = getTransferListener();
+    if(session instanceof DefaultRepositorySystemSession def) {
+      def.setTransferListener(transferListener);
+    }
+    if(session instanceof FilterRepositorySystemSession filter) {
+      filter.setTransferListener(transferListener);
+    }
+    if(transferListener == session.getTransferListener()) {
+      this.transferListener = null;
+    } else {
+      this.transferListener = transferListener;
+    }
     return origTransferListener;
   }
 
   public SessionData setData(SessionData data) {
-    DefaultRepositorySystemSession session = getSession();
-    SessionData origSessionData = session.getData();
-    session.setData(data);
+    SessionData origSessionData = getData();
+    if(session instanceof DefaultRepositorySystemSession def) {
+      def.setData(data);
+    }
+    if(session instanceof FilterRepositorySystemSession filter) {
+      filter.setData(data);
+    }
+    if(data == session.getData()) {
+      this.data = null;
+    } else {
+      this.data = data;
+    }
     return origSessionData;
   }
 
   @Override
-  protected DefaultRepositorySystemSession getSession() {
+  protected RepositorySystemSession getSession() {
     return this.session;
   }
 }

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

@@ -32,7 +32,7 @@
 import java.util.function.Function;
 
 import org.eclipse.aether.ConfigurationProperties;
-import org.eclipse.aether.DefaultRepositorySystemSession;
+import org.eclipse.aether.RepositorySystemSession;
 import org.eclipse.aether.transfer.TransferListener;
 import org.eclipse.core.runtime.CoreException;
 import org.eclipse.core.runtime.IProgressMonitor;
@@ -60,7 +60,6 @@
 import org.apache.maven.lifecycle.internal.LifecycleExecutionPlanCalculator;
 import org.apache.maven.lifecycle.internal.MojoExecutor;
 import org.apache.maven.plugin.BuildPluginManager;
-import org.eclipse.m2e.internal.maven.compat.LifecycleExecutionPlanCalculatorFacade;
 import org.apache.maven.plugin.LegacySupport;
 import org.apache.maven.plugin.MojoExecution;
 import org.apache.maven.project.DefaultProjectBuildingRequest;
@@ -79,6 +78,7 @@
 import org.eclipse.m2e.core.embedder.MavenSettingsLocations;
 import org.eclipse.m2e.core.internal.MavenPluginActivator;
 import org.eclipse.m2e.core.internal.Messages;
+import org.eclipse.m2e.internal.maven.compat.LifecycleExecutionPlanCalculatorFacade;
 import org.eclipse.m2e.internal.maven.compat.ReadonlyMavenExecutionRequest;
 
 
@@ -593,7 +593,7 @@ public IComponentLookup getComponentLookup() {
 
   static FilterRepositorySystemSession createRepositorySession(MavenExecutionRequest request,
       IMavenConfiguration configuration, IComponentLookup lookup) throws CoreException {
-    DefaultRepositorySystemSession session = (DefaultRepositorySystemSession) ((DefaultMaven) lookup
+    RepositorySystemSession session = ((DefaultMaven) lookup
         .lookup(Maven.class)).newRepositorySession(request);
     String updatePolicy = configuration.getGlobalUpdatePolicy();
     return new FilterRepositorySystemSession(session, request.isUpdateSnapshots() ? null : updatePolicy);