diff --git a/src/main/java/org/apache/maven/plugins/source/AbstractSourceJarMojo.java b/src/main/java/org/apache/maven/plugins/source/AbstractSourceJarMojo.java
index 802a1fd..d660355 100644
--- a/src/main/java/org/apache/maven/plugins/source/AbstractSourceJarMojo.java
+++ b/src/main/java/org/apache/maven/plugins/source/AbstractSourceJarMojo.java
@@ -431,10 +431,12 @@ protected MavenArchiver createArchiver() throws MojoException {
                     project.getBuild().getResources();
 
             for (org.apache.maven.api.model.Resource r : resources) {
-                if (r.getDirectory().endsWith("maven-shared-archive-resources")) {
+                Path resourceDirectory = Paths.get(r.getDirectory());
+                Path directoryName = resourceDirectory.getFileName();
+                if (directoryName != null && "maven-shared-archive-resources".equals(directoryName.toString())) {
                     addDirectory(
                             archiver.getArchiver(),
-                            Paths.get(r.getDirectory()),
+                            resourceDirectory,
                             getCombinedIncludes(null),
                             getCombinedExcludes(null));
                 }
diff --git a/src/test/java/org/apache/maven/plugins/source/AbstractSourceJarMojoTest.java b/src/test/java/org/apache/maven/plugins/source/AbstractSourceJarMojoTest.java
new file mode 100644
index 0000000..bea5362
--- /dev/null
+++ b/src/test/java/org/apache/maven/plugins/source/AbstractSourceJarMojoTest.java
@@ -0,0 +1,109 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.maven.plugins.source;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Arrays;
+import java.util.List;
+import java.util.stream.Collectors;
+
+import org.apache.maven.api.Project;
+import org.apache.maven.api.model.Build;
+import org.apache.maven.api.model.Resource;
+import org.apache.maven.api.plugin.Log;
+import org.codehaus.plexus.archiver.FileSet;
+import org.codehaus.plexus.archiver.jar.JarArchiver;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
+import org.mockito.ArgumentCaptor;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.mockito.Mockito.mock;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.verifyNoInteractions;
+import static org.mockito.Mockito.when;
+
+class AbstractSourceJarMojoTest {
+
+    private static final String SHARED_ARCHIVE_RESOURCES = "maven-shared-archive-resources";
+
+    @Test
+    void testSharedArchiveResourcesDirectoryIsAdded(@TempDir Path tempDir) throws Exception {
+        Path sharedArchiveResources = Files.createDirectory(tempDir.resolve(SHARED_ARCHIVE_RESOURCES));
+
+        JarArchiver jarArchiver = mock(JarArchiver.class);
+        AbstractSourceJarMojo mojo = mojoWithResourceDirectories(jarArchiver, sharedArchiveResources);
+
+        mojo.createArchiver();
+
+        ArgumentCaptor<FileSet> fileSet = ArgumentCaptor.forClass(FileSet.class);
+        verify(jarArchiver).addFileSet(fileSet.capture());
+        assertEquals(sharedArchiveResources.toFile(), fileSet.getValue().getDirectory());
+    }
+
+    /**
+     * A directory is the shared archive resources directory only when that is its name. A path that merely ends with
+     * those characters, such as one produced by appending a suffix to an unrelated directory, is a different directory
+     * and must not be added.
+     */
+    @Test
+    void testDirectoryEndingWithSharedArchiveResourcesIsNotAdded(@TempDir Path tempDir) throws Exception {
+        Path suffixedName = Files.createDirectory(tempDir.resolve("tmp-" + SHARED_ARCHIVE_RESOURCES));
+
+        JarArchiver jarArchiver = mock(JarArchiver.class);
+        AbstractSourceJarMojo mojo = mojoWithResourceDirectories(jarArchiver, suffixedName);
+
+        mojo.createArchiver();
+
+        verifyNoInteractions(jarArchiver);
+    }
+
+    @Test
+    void testOnlySharedArchiveResourcesDirectoryIsAddedWhenBothArePresent(@TempDir Path tempDir) throws Exception {
+        Path suffixedName = Files.createDirectory(tempDir.resolve("tmp-" + SHARED_ARCHIVE_RESOURCES));
+        Path sharedArchiveResources = Files.createDirectory(tempDir.resolve(SHARED_ARCHIVE_RESOURCES));
+
+        JarArchiver jarArchiver = mock(JarArchiver.class);
+        AbstractSourceJarMojo mojo = mojoWithResourceDirectories(jarArchiver, suffixedName, sharedArchiveResources);
+
+        mojo.createArchiver();
+
+        ArgumentCaptor<FileSet> fileSet = ArgumentCaptor.forClass(FileSet.class);
+        verify(jarArchiver).addFileSet(fileSet.capture());
+        assertEquals(sharedArchiveResources.toFile(), fileSet.getValue().getDirectory());
+    }
+
+    private static AbstractSourceJarMojo mojoWithResourceDirectories(JarArchiver jarArchiver, Path... directories) {
+        List<Resource> resources = Arrays.stream(directories)
+                .map(directory ->
+                        Resource.newBuilder().directory(directory.toString()).build())
+                .collect(Collectors.toList());
+
+        Project project = mock(Project.class);
+        when(project.getBuild())
+                .thenReturn(Build.newBuilder().resources(resources).build());
+
+        AbstractSourceJarMojo mojo = new SourceJarMojo();
+        mojo.project = project;
+        mojo.jarArchiver = jarArchiver;
+        mojo.log = mock(Log.class);
+        return mojo;
+    }
+}