GP-4608: Improving how we handle loading classes with the same name

Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassDir.java

@@ -16,7 +16,7 @@
 package ghidra.util.classfinder;
 
 import java.io.File;
-import java.util.Set;
+import java.util.List;
 
 import ghidra.util.exception.CancelledException;
 import ghidra.util.task.TaskMonitor;
@@ -33,8 +33,8 @@ class ClassDir {
 		classPackage = new ClassPackage(dir, "", monitor);
 	}
 
-	void getClasses(Set<ClassFileInfo> set, TaskMonitor monitor) throws CancelledException {
+	void getClasses(List<ClassFileInfo> list, TaskMonitor monitor) throws CancelledException {
-		classPackage.getClasses(set, monitor);
+		classPackage.getClasses(list, monitor);
 	}
 
 	String getDirPath() {

Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassJar.java

@@ -62,8 +62,8 @@ class ClassJar implements ClassLocation {
 	}
 
 	@Override
-	public void getClasses(Set<ClassFileInfo> set, TaskMonitor monitor) {
+	public void getClasses(List<ClassFileInfo> list, TaskMonitor monitor) {
-		set.addAll(classes);
+		list.addAll(classes);
 	}
 
 	private void scanJar(TaskMonitor monitor) throws CancelledException {

Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassLocation.java

@@ -15,7 +15,7 @@
  */
 package ghidra.util.classfinder;
 
-import java.util.Set;
+import java.util.List;
 
 import ghidra.util.exception.CancelledException;
 import ghidra.util.task.TaskMonitor;
@@ -27,5 +27,5 @@ interface ClassLocation {
 
 	public static final String CLASS_EXT = ".class";
 
-	public void getClasses(Set<ClassFileInfo> set, TaskMonitor monitor) throws CancelledException;
+	public void getClasses(List<ClassFileInfo> list, TaskMonitor monitor) throws CancelledException;
 }

Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassPackage.java

@@ -89,15 +89,16 @@ class ClassPackage implements ClassLocation {
 	}
 
 	@Override
-	public void getClasses(Set<ClassFileInfo> set, TaskMonitor monitor) throws CancelledException {
+	public void getClasses(List<ClassFileInfo> list, TaskMonitor monitor)
+			throws CancelledException {
 
-		set.addAll(classes);
+		list.addAll(classes);
 
 		Iterator<ClassPackage> it = children.iterator();
 		while (it.hasNext()) {
 			monitor.checkCancelled();
 			ClassPackage subPkg = it.next();
-			subPkg.getClasses(set, monitor);
+			subPkg.getClasses(list, monitor);
 		}
 	}
 

Ghidra/Framework/Generic/src/main/java/ghidra/util/classfinder/ClassSearcher.java

@@ -30,8 +30,6 @@ import java.util.stream.Collectors;
 
 import javax.swing.event.ChangeListener;
 
-import org.apache.commons.collections4.BidiMap;
-import org.apache.commons.collections4.bidimap.DualHashBidiMap;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -81,7 +79,7 @@ public class ClassSearcher {
 	private static List<Class<?>> FILTER_CLASSES = Arrays.asList(ExtensionPoint.class);
 	private static Pattern extensionPointSuffixPattern;
 	private static Map<String, Set<ClassFileInfo>> extensionPointSuffixToInfoMap;
-	private static BidiMap<ClassFileInfo, Class<?>> loadedCache = new DualHashBidiMap<>();
+	private static Map<ClassFileInfo, Class<?>> loadedCache = new HashMap<>();
 	private static Set<ClassFileInfo> falsePositiveCache = new HashSet<>();
 	private static volatile boolean hasSearched;
 	private static volatile boolean isSearching;
@@ -187,12 +185,6 @@ public class ClassSearcher {
 			Class<?> c = loadedCache.get(info);
 			if (c == null) {
 				c = loadExtensionPoint(info.path(), info.name());
-				ClassFileInfo existing = loadedCache.getKey(c);
-				if (existing != null) {
-					log.info(
-						"Skipping load of class '%s' from '%s'. Already loaded from '%s'."
-								.formatted(info.name(), info.path(), existing.path()));
-				}
 				if (c == null) {
 					falsePositiveCache.add(info);
 					continue;
@@ -418,8 +410,8 @@ public class ClassSearcher {
 			throws CancelledException {
 		log.info("Searching for classes...");
 
-		Set<ClassDir> classDirs = new HashSet<>();
+		List<ClassDir> classDirs = new ArrayList<>();
-		Set<ClassJar> classJars = new HashSet<>();
+		List<ClassJar> classJars = new ArrayList<>();
 
 		for (String searchPath : gatherSearchPaths()) {
 			String lcSearchPath = searchPath.toLowerCase();
@@ -441,17 +433,31 @@ public class ClassSearcher {
 			}
 		}
 
-		Set<ClassFileInfo> classSet = new HashSet<>();
+		List<ClassFileInfo> classList = new ArrayList<>();
 		for (ClassDir dir : classDirs) {
 			monitor.checkCancelled();
-			dir.getClasses(classSet, monitor);
+			dir.getClasses(classList, monitor);
 		}
 		for (ClassJar jar : classJars) {
 			monitor.checkCancelled();
-			jar.getClasses(classSet, monitor);
+			jar.getClasses(classList, monitor);
 		}
 
-		return classSet.stream()
+		// We can't load more than one class with the same name, so de-duplicate them
+		Map<String, ClassFileInfo> uniqueClassMap = new HashMap<>();
+		for (ClassFileInfo info : classList) {
+			ClassFileInfo existing = uniqueClassMap.get(info.name());
+			if (existing == null) {
+				uniqueClassMap.put(info.name(), info);
+			}
+			else {
+				log.info("Ignoring class '%s' from '%s'. Already found at '%s'."
+						.formatted(info.name(), info.path(), existing.path()));
+			}
+		}
+
+		return uniqueClassMap.values()
+				.stream()
 				.collect(Collectors.groupingBy(ClassFileInfo::suffix, Collectors.toSet()));
 	}
 

Ghidra/Framework/Utility/src/main/java/ghidra/GhidraLauncher.java

@@ -165,6 +165,15 @@ public class GhidraLauncher {
 			else { /* Eclipse dev mode */
 				// Support loading pre-built, jar-based, non-repo extensions in Eclipse dev mode
 				addExtensionJarPaths(classpathList, modules, layout);
+
+				// Eclipse launches the Utility module, so it's already on the classpath.  We don't
+				// want to add it a second time, so remove the one we discovered.
+				GModule utilityModule = modules.get("Utility");
+				if (utilityModule == null) {
+					throw new IOException("Failed to find the 'Utility' module!");
+				}
+				classpathList.removeIf(
+					e -> e.startsWith(utilityModule.getModuleRoot().getAbsolutePath()));
 			}
 
 			// In development mode, jars do not live in module directories. Instead, each jar lives