fix: prevent importing classes which are already imported via *

src/main/java/spoon/support/compiler/jdt/JDTImportBuilder.java

@@ -20,8 +20,10 @@
 import spoon.reflect.factory.Factory;
 import spoon.reflect.reference.CtReference;
 
+import java.util.Arrays;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Optional;
 import java.util.Set;
 
 /**
@@ -59,9 +61,8 @@ void build() {
 					int lastDot = importName.lastIndexOf('.');
 					String packageName = importName.substring(0, lastDot);
 
-					// only get package from the model by traversing from rootPackage the model
-					// it does not use reflection to achieve that
-					CtPackage ctPackage = this.factory.Package().get(packageName);
+					// load package by looking up in the class loader or in the model being built
+					CtPackage ctPackage = loadPackage(packageName);
 
 					if (ctPackage != null) {
 						this.imports.add(createImportWithPosition(ctPackage.getReference(), importRef));
@@ -138,6 +139,23 @@ private CtImport createUnresolvedImportWithPosition(String ref, boolean isStatic
 		return imprt;
 	}
 
+	private CtPackage loadPackage(String packageName) {
+		// get all packages known for the current class loader and the ones which are accessible from it
+		Package[] allPackagesInAllClassLoaders = Package.getPackages();
+
+		Optional<Package> requiredPackage = Arrays.stream(allPackagesInAllClassLoaders)
+				.filter(pkg -> pkg.getName().equals(packageName))
+				.findAny();
+		if (requiredPackage.isPresent()) {
+			CtPackage ctPackage = factory.createPackage();
+			ctPackage.setSimpleName(requiredPackage.get().getName());
+			return ctPackage;
+		}
+
+		// get package by traversing the model
+		return factory.Package().get(packageName);
+	}
+
 	private CtType getOrLoadClass(String className) {
 		CtType klass = this.factory.Type().get(className);
 

src/test/java/spoon/reflect/visitor/ImportCleanerTest.java

@@ -1,6 +1,6 @@
 package spoon.reflect.visitor;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import spoon.Launcher;
 import spoon.reflect.CtModel;
 import spoon.reflect.declaration.CtCompilationUnit;
@@ -16,13 +16,19 @@
 public class ImportCleanerTest {
 
 	@Test
-	public void testDoesNotDuplicateUnresolvedImports() {
+	void testDoesNotImportClassesIfAlreadyImportedViaWildCard() {
+		// contract: The import cleaner should not import classes if they are encompassed in wildcard import.
+		testImportCleanerDoesNotAlterImports("src/test/resources/importCleaner/WildCardImport.java", "WildCardImport");
+	}
+
+	@Test
+	void testDoesNotDuplicateUnresolvedImports() {
 	    // contract: The import cleaner should not duplicate unresolved imports
 		testImportCleanerDoesNotAlterImports("./src/test/resources/unresolved/UnresolvedImport.java", "UnresolvedImport");
 	}
 
 	@Test
-	public void testDoesNotImportInheritedStaticMethod() {
+	void testDoesNotImportInheritedStaticMethod() {
 		// contract: The import cleaner should not import static attributes that are inherited
 		testImportCleanerDoesNotAlterImports("./src/test/resources/inherit-static-method", "Derived");
 	}

src/test/resources/importCleaner/WildCardImport.java

@@ -0,0 +1,5 @@
+import java.util.*;
+
+public class WildCardImport {
+    private static List<Integer> x = new ArrayList<>();
+}