@@ -1,6 +1,7 @@
 package processing.mode.java.pdex;
 
 import com.google.classpath.ClassPath;
+import com.google.classpath.ClassPathFactory;
 import com.google.classpath.RegExpResourceFilter;
 
 import org.eclipse.jdt.core.compiler.IProblem;
@@ -44,6 +45,7 @@
 import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicReference;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 import java.util.regex.Pattern;
@@ -1106,6 +1108,8 @@ private void handleSketchProblems(PreprocessedSketch ps) {
         }
       }
 
+      AtomicReference<ClassPath> searchClassPath = new AtomicReference<>(null);
+
       if (problems.isEmpty()) {
         List<Problem> cuProblems = Arrays.stream(iproblems)
             // Filter Warnings if they are not enabled
@@ -1129,7 +1133,8 @@ private void handleSketchProblems(PreprocessedSketch ps) {
 
               // Handle import suggestions
               if (JavaMode.importSuggestEnabled && isUndefinedTypeProblem(iproblem)) {
-                ClassPath cp = ps.searchClassPath;
+                ClassPath cp = searchClassPath.updateAndGet(prev -> prev != null ?
+                    prev : new ClassPathFactory().createFromPaths(ps.searchClassPathArray));
                 String[] s = suggCache.computeIfAbsent(iproblem.getArguments()[0],
                                                        name -> getImportSuggestions(cp, name));
                 p.setImportSuggestions(s);
 
@@ -26,7 +26,7 @@ public class PreprocessedSketch {
   public final ClassPath classPath;
   public final URLClassLoader classLoader;
 
-  public final ClassPath searchClassPath;
+  public final String[] searchClassPathArray;
 
   public final int[] tabStartOffsets;
 
@@ -206,7 +206,7 @@ public static class Builder {
     public ClassPath classPath;
     public URLClassLoader classLoader;
 
-    public ClassPath searchClassPath;
+    public String[] searchClassPathArray;
 
     public int[] tabStartOffsets = new int[0];
 
@@ -242,7 +242,7 @@ private PreprocessedSketch(Builder b) {
     classPath = b.classPath;
     classLoader = b.classLoader;
 
-    searchClassPath = b.searchClassPath;
+    searchClassPathArray = b.searchClassPathArray;
 
     tabStartOffsets = b.tabStartOffsets;
 
 
@@ -341,7 +341,7 @@ private PreprocessedSketch preprocessSketch(PreprocessedSketch prevResult) {
 
       boolean rebuildClassPath = reloadCodeFolder || rebuildLibraryClassPath ||
           prevResult.classLoader == null || prevResult.classPath == null ||
-          prevResult.classPathArray == null || prevResult.searchClassPath == null;
+          prevResult.classPathArray == null || prevResult.searchClassPathArray == null;
 
       if (reloadCodeFolder) {
         codeFolderClassPath = buildCodeFolderClassPath(sketch);
@@ -381,13 +381,12 @@ private PreprocessedSketch preprocessSketch(PreprocessedSketch prevResult) {
           searchClassPath.addAll(coreLibraryClassPath);
           searchClassPath.addAll(codeFolderClassPath);
 
-          String[] searchClassPathArray = searchClassPath.stream().toArray(String[]::new);
-          result.searchClassPath = classPathFactory.createFromPaths(searchClassPathArray);
+          result.searchClassPathArray = searchClassPath.stream().toArray(String[]::new);
         }
       } else {
         result.classLoader = prevResult.classLoader;
         result.classPath = prevResult.classPath;
-        result.searchClassPath = prevResult.searchClassPath;
+        result.searchClassPathArray = prevResult.searchClassPathArray;
         result.classPathArray = prevResult.classPathArray;
       }
     }