look for usages in text files

java/java-impl/src/com/intellij/codeInsight/daemon/impl/PostHighlightingPass.java

@@ -41,6 +41,9 @@ import com.intellij.codeInspection.unusedImport.UnusedImportLocalInspection;
 import com.intellij.codeInspection.unusedParameters.UnusedParametersInspection;
 import com.intellij.codeInspection.unusedSymbol.UnusedSymbolLocalInspection;
 import com.intellij.codeInspection.util.SpecialAnnotationsUtil;
+import com.intellij.find.FindManager;
+import com.intellij.find.findUsages.FindUsagesManager;
+import com.intellij.find.impl.FindManagerImpl;
 import com.intellij.lang.Language;
 import com.intellij.lang.annotation.HighlightSeverity;
 import com.intellij.openapi.application.ApplicationManager;
@@ -68,14 +71,11 @@ import com.intellij.psi.jsp.JspSpiUtil;
 import com.intellij.psi.search.GlobalSearchScope;
 import com.intellij.psi.search.PsiSearchHelper;
 import com.intellij.psi.search.SearchScope;
-import com.intellij.psi.search.searches.MethodReferencesSearch;
 import com.intellij.psi.search.searches.OverridingMethodsSearch;
-import com.intellij.psi.search.searches.ReferencesSearch;
 import com.intellij.psi.search.searches.SuperMethodsSearch;
 import com.intellij.psi.util.PropertyUtil;
 import com.intellij.psi.util.PsiUtilBase;
 import com.intellij.util.Processor;
-import com.intellij.util.Query;
 import gnu.trove.THashSet;
 import gnu.trove.TObjectIntHashMap;
 import org.jetbrains.annotations.NotNull;
@@ -549,15 +549,13 @@ public class PostHighlightingPass extends TextEditorHighlightingPass {
       }
       if (!canbeReferencedViaWeirdNames(member)) return true;
     }
+    FindUsagesManager findUsagesManager = ((FindManagerImpl)FindManager.getInstance(myProject)).getFindUsagesManager();
+    boolean used = findUsagesManager.isUsed(member, scope);
 
-    Query<PsiReference> query = member instanceof PsiMethod
-                                ? MethodReferencesSearch.search((PsiMethod)member, scope, true)
-                                : ReferencesSearch.search(member, scope, true);
-    final PsiReference first = query.findFirst();
-    if (first == null && member instanceof PsiEnumConstant) {
+    if (!used && member instanceof PsiEnumConstant) {
       return checkEnumValuesUsages(member, progress);
     }
-    return first == null;
+    return !used;
   }
 
   private boolean checkEnumValuesUsages(PsiMember member, ProgressIndicator progress) {

java/java-tests/testData/codeInsight/daemonCodeAnalyzer/advHighlighting/UnusedNonPrivateMembersReferencedFromText.java

@@ -0,0 +1,3 @@
+public class <warning descr="Class 'XXX' is never used">XXX</warning> {
+}
+

java/java-tests/testSrc/com/intellij/codeInsight/daemon/LightAdvHighlightingTest.java

@@ -1,6 +1,7 @@
 package com.intellij.codeInsight.daemon;
 
 import com.intellij.ExtensionPoints;
+import com.intellij.codeInsight.daemon.impl.HighlightInfo;
 import com.intellij.codeInspection.LocalInspectionTool;
 import com.intellij.codeInspection.accessStaticViaInstance.AccessStaticViaInstance;
 import com.intellij.codeInspection.deadCode.UnusedDeclarationInspection;
@@ -23,6 +24,7 @@ import com.intellij.openapi.extensions.ExtensionPoint;
 import com.intellij.openapi.extensions.Extensions;
 import com.intellij.openapi.fileTypes.StdFileTypes;
 import com.intellij.openapi.roots.LanguageLevelProjectExtension;
+import com.intellij.openapi.vfs.VfsUtil;
 import com.intellij.pom.java.LanguageLevel;
 import com.intellij.psi.*;
 import com.intellij.psi.xml.XmlAttribute;
@@ -239,6 +241,26 @@ public class LightAdvHighlightingTest extends LightDaemonAnalyzerTestCase {
       point.unregisterExtension(extension);
     }
   }
+  public void testUnusedNonPrivateMembersReferencedFromText() throws Exception {
+    UnusedDeclarationInspection deadCodeInspection = new UnusedDeclarationInspection();
+    enableInspectionTool(deadCodeInspection);
+
+    doTest(true, false);
+    ApplicationManager.getApplication().runWriteAction(new Runnable() {
+      public void run() {
+        PsiFile txt = myFile.getParent().createFile("x.txt");
+        try {
+          VfsUtil.saveText(txt.getVirtualFile(), "XXX");
+        }
+        catch (IOException e) {
+          throw new RuntimeException(e);
+        }
+      }
+    });
+
+    List<HighlightInfo> infos = filter(doHighlighting(), HighlightSeverity.WARNING);
+    assertEmpty(infos);
+  }
 
   public void testNamesHighlighting() throws Exception {
     LanguageLevelProjectExtension.getInstance(getJavaFacade().getProject()).setLanguageLevel(LanguageLevel.JDK_1_5);

platform/lang-impl/src/com/intellij/find/findUsages/FindUsagesManager.java

@@ -72,6 +72,7 @@ import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
 import java.util.concurrent.CopyOnWriteArrayList;
+import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 
 public class FindUsagesManager implements JDOMExternalizable {
@@ -310,6 +311,24 @@ public class FindUsagesManager implements JDOMExternalizable {
     return findUsagesOptions.searchScope;
   }
 
+  public boolean isUsed(@NotNull PsiElement element, @NotNull SearchScope scope) {
+    FindUsagesHandler handler = getFindUsagesHandler(element, false);
+    if (handler == null) return false;
+    final UsageInfoToUsageConverter.TargetElementsDescriptor descriptor =
+      new UsageInfoToUsageConverter.TargetElementsDescriptor(handler.getPrimaryElements(), handler.getSecondaryElements());
+    FindUsagesOptions findUsagesOptions = handler.getFindUsagesOptions();
+    findUsagesOptions.searchScope = scope;
+    UsageSearcher usageSearcher = createUsageSearcher(descriptor, handler, findUsagesOptions, null);
+    final AtomicBoolean used = new AtomicBoolean();
+    usageSearcher.generate(new Processor<Usage>() {
+      public boolean process(final Usage usage) {
+        used.set(true);
+        return false;
+      }
+    });
+    return used.get();
+  }
+
   // return null on failure or cancel
   @Nullable
   public UsageViewPresentation processUsages(FindUsagesHandler handler, @NotNull final Processor<Usage> processor) {