Merge pull request #8948 from mbien/cp-hint-init-performance

Refactoring: Improve listClassPathHints() performance

Author: mbien

java/java.hints.declarative/src/org/netbeans/modules/java/hints/declarative/DeclarativeHintRegistry.java

@@ -106,7 +106,7 @@ public Collection<? extends HintDescription> computeHints(final ClassPath cp, At
     }
 
     public static Collection<? extends HintDescription> join(Map<HintMetadata, Collection<? extends HintDescription>> hints) {
-        List<HintDescription> descs = new LinkedList<>();
+        List<HintDescription> descs = new ArrayList<>();
 
         for (Collection<? extends HintDescription> c : hints.values()) {
             descs.addAll(c);

java/spi.java.hints/src/org/netbeans/modules/java/hints/spiimpl/Utilities.java

@@ -94,6 +94,7 @@
 import java.lang.ref.WeakReference;
 import java.net.URI;
 import java.nio.CharBuffer;
+import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
@@ -163,8 +164,6 @@
 import org.openide.util.NbCollections;
 import org.openide.util.WeakListeners;
 import org.openide.util.lookup.ServiceProvider;
-
-import static com.sun.source.tree.CaseTree.CaseKind.STATEMENT;
 import org.netbeans.api.annotations.common.NullAllowed;
 import org.netbeans.modules.java.hints.providers.spi.HintMetadata;
 import org.netbeans.modules.refactoring.spi.ui.RefactoringUI;
@@ -175,6 +174,8 @@
 import org.openide.util.Parameters;
 import org.openide.windows.TopComponent;
 
+import static com.sun.source.tree.CaseTree.CaseKind.STATEMENT;
+
 /**
  *
  * @author Jan Lahoda
@@ -288,32 +289,36 @@ public static List<HintDescription> listAllHints(Set<ClassPath> cps) {
     }
 
     public static List<HintDescription> listClassPathHints(Set<ClassPath> sourceCPs, Set<ClassPath> binaryCPs) {
-        List<HintDescription> result = new LinkedList<>();
-        Set<FileObject> roots = new HashSet<>();
 
+        // deduplicate before running queries
+        Set<FileObject> unique = new HashSet<>(128);
         for (ClassPath cp : binaryCPs) {
-            for (FileObject r : cp.getRoots()) {
-                Result2 src = SourceForBinaryQuery.findSourceRoots2(r.toURL());
+            unique.addAll(Arrays.asList(cp.getRoots()));
+        }
 
-                if (src != null && src.preferSources()) {
-                    roots.addAll(Arrays.asList(src.getRoots()));
-                } else {
-                    roots.add(r);
-                }
+        Set<FileObject> roots = new HashSet<>();
+
+        for (FileObject fo : unique) {
+            Result2 src = SourceForBinaryQuery.findSourceRoots2(fo.toURL());
+            if (src != null && src.preferSources()) {
+                roots.addAll(Arrays.asList(src.getRoots()));
+            } else {
+                roots.add(fo);
             }
         }
 
         Set<ClassPath> cps = new HashSet<>(sourceCPs);
-
         cps.add(ClassPathSupport.createClassPath(roots.toArray(FileObject[]::new)));
 
         ClassPath cp = ClassPathSupport.createProxyClassPath(cps.toArray(ClassPath[]::new));
 
-        for (ClassPathBasedHintProvider p : Lookup.getDefault().lookupAll(ClassPathBasedHintProvider.class)) {
-            result.addAll(p.computeHints(cp, new AtomicBoolean()));
+        List<HintDescription> descriptions = new ArrayList<>();
+
+        for (ClassPathBasedHintProvider prov : Lookup.getDefault().lookupAll(ClassPathBasedHintProvider.class)) {
+            descriptions.addAll(prov.computeHints(cp, new AtomicBoolean()));
         }
 
-        return result;
+        return descriptions;
     }
 
     public static Tree parseAndAttribute(CompilationInfo info, String pattern, Scope scope) {