diff --git a/ExtendedApi/src/com/intellij/extapi/psi/ASTWrapperPsiElement.java b/ExtendedApi/src/com/intellij/extapi/psi/ASTWrapperPsiElement.java
index 6a895aea19bf..06ab7ec28c49 100644
--- a/ExtendedApi/src/com/intellij/extapi/psi/ASTWrapperPsiElement.java
+++ b/ExtendedApi/src/com/intellij/extapi/psi/ASTWrapperPsiElement.java
@@ -45,7 +45,8 @@ public class ASTWrapperPsiElement extends ElementBase implements PsiElement, Nav
   }
 
   public PsiManager getManager() {
-    return getParent().getManager();
+    final PsiElement parent = getParent();
+    return parent != null ? parent.getManager() : null;
   }
 
   public PsiElement[] getChildren() {
@@ -235,7 +236,7 @@ public class ASTWrapperPsiElement extends ElementBase implements PsiElement, Nav
   }
 
   public SearchScope getUseScope() {
-    throw new UnsupportedOperationException();
+    return getManager().getSearchHelper().getUseScope(this);
   }
 
   public ItemPresentation getPresentation() {
diff --git a/openapi/src/com/intellij/lang/Language.java b/openapi/src/com/intellij/lang/Language.java
index 70f1cbc79f33..1bcb8fe22066 100644
--- a/openapi/src/com/intellij/lang/Language.java
+++ b/openapi/src/com/intellij/lang/Language.java
@@ -1,10 +1,13 @@
 package com.intellij.lang;
 
 import com.intellij.codeFormatting.PseudoTextBuilder;
+import com.intellij.lang.cacheBuilder.WordsScanner;
+import com.intellij.lang.folding.FoldingBuilder;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.fileTypes.PlainSyntaxHighlighter;
 import com.intellij.openapi.fileTypes.SyntaxHighlighter;
 import com.intellij.openapi.project.Project;
+import com.intellij.psi.tree.IElementType;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -47,6 +50,18 @@ public abstract class Language {
     return null;
   }
 
+  public WordsScanner getWordsScanner() {
+    return null;
+  }
+
+  public boolean mayHaveReferences(IElementType token) {
+    return false;
+  }
+
+  public FoldingBuilder getFoldingBuilder() {
+    return null;
+  }
+
   public String toString() {
     return "Language: " + myID;
   }
diff --git a/openapi/src/com/intellij/lang/cacheBuilder/DefaultWordsScanner.java b/openapi/src/com/intellij/lang/cacheBuilder/DefaultWordsScanner.java
new file mode 100644
index 000000000000..2c1f6b3aa7e9
--- /dev/null
+++ b/openapi/src/com/intellij/lang/cacheBuilder/DefaultWordsScanner.java
@@ -0,0 +1,82 @@
+package com.intellij.lang.cacheBuilder;
+
+import com.intellij.lexer.Lexer;
+import com.intellij.psi.tree.IElementType;
+import com.intellij.psi.tree.TokenSet;
+import com.intellij.util.Processor;
+import com.intellij.util.text.CharArrayCharSequence;
+import com.intellij.util.text.CharArrayUtil;
+
+/**
+ * Created by IntelliJ IDEA.
+ * User: max
+ * Date: Jan 31, 2005
+ * Time: 9:12:33 PM
+ * To change this template use File | Settings | File Templates.
+ */
+public class DefaultWordsScanner implements WordsScanner {
+  private Lexer myLexer;
+  private TokenSet myIdentifierTokenSet;
+  private TokenSet myCommentTokenSet;
+  private TokenSet myLiteralTokenSet;
+
+  public DefaultWordsScanner(final Lexer lexer, final TokenSet identifierTokenSet, final TokenSet commentTokenSet, final TokenSet literalTokenSet) {
+    myLexer = lexer;
+    myIdentifierTokenSet = identifierTokenSet;
+    myCommentTokenSet = commentTokenSet;
+    myLiteralTokenSet = literalTokenSet;
+  }
+
+  public void processWords(CharSequence fileText, Processor<WordOccurence> processor) {
+    char[] chars = CharArrayUtil.fromSequence(fileText);
+    myLexer.start(chars, 0, fileText.length());
+    while (myLexer.getTokenType() != null) {
+      final IElementType type = myLexer.getTokenType();
+      if (myIdentifierTokenSet.isInSet(type)) {
+        if (!processor.process(new WordOccurence(currentTokenText(chars), WordOccurence.Kind.CODE))) return;
+      }
+      else if (myCommentTokenSet.isInSet(type)) {
+        if (!stripWords(processor, currentTokenText(chars), WordOccurence.Kind.COMMENTS)) return;
+      }
+      else if (myLiteralTokenSet.isInSet(type)) {
+        if (!stripWords(processor, currentTokenText(chars), WordOccurence.Kind.LITERALS)) return;
+      }
+      myLexer.advance();
+    }
+  }
+
+  /**
+   * This code seems strange but it is more effective as Character.isJavaIdentifier_xxx_ quite hard operation due to unicode
+   */
+  private static boolean stripWords(final Processor<WordOccurence> processor,
+                                    final CharArrayCharSequence tokenText,
+                                    final WordOccurence.Kind kind) {
+    int index = 0;
+
+    ScanWordsLoop:
+      while(true){
+        while(true){
+          if (index == tokenText.length()) break ScanWordsLoop;
+          char c = tokenText.charAt(index);
+          if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || (Character.isJavaIdentifierStart(c) && c != '$')) break;
+          index++;
+        }
+        int index1 = index;
+        while(true){
+          index++;
+          if (index == tokenText.length()) break;
+          char c = tokenText.charAt(index);
+          if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9')) continue;
+          if (!Character.isJavaIdentifierPart(c) || c == '$') break;
+        }
+        if (index - index1 > 100) continue; // Strange limit but we should have some!
+
+        if (!processor.process(new WordOccurence(tokenText.subSequence(index1, index), kind))) return false;
+      }
+    return true;
+  }
+
+  private CharArrayCharSequence currentTokenText(final char[] chars) {
+    return new CharArrayCharSequence(chars, myLexer.getTokenStart(), myLexer.getTokenEnd());
+  }
+}
diff --git a/openapi/src/com/intellij/lang/cacheBuilder/WordOccurence.java b/openapi/src/com/intellij/lang/cacheBuilder/WordOccurence.java
new file mode 100644
index 000000000000..c2e70e83f6a7
--- /dev/null
+++ b/openapi/src/com/intellij/lang/cacheBuilder/WordOccurence.java
@@ -0,0 +1,42 @@
+package com.intellij.lang.cacheBuilder;
+
+/**
+ * Created by IntelliJ IDEA.
+ * User: max
+ * Date: Jan 31, 2005
+ * Time: 9:09:06 PM
+ * To change this template use File | Settings | File Templates.
+ */
+public class WordOccurence {
+  private Kind myKind;
+  private CharSequence myText;
+
+  public WordOccurence(final CharSequence text, final Kind kind) {
+    myKind = kind;
+    myText = text;
+  }
+
+  public Kind getKind() {
+    return myKind;
+  }
+
+  public CharSequence getText() {
+    return myText;
+  }
+
+  public static class Kind {
+    public static final Kind CODE = new Kind("CODE");
+    public static final Kind COMMENTS = new Kind("COMMENTS");
+    public static final Kind LITERALS = new Kind("LITERALS");
+
+    private String myName;
+
+    private Kind(String name){
+      myName = name;
+    }
+
+    public String toString() {
+      return "WordOccurence.Kind(" + myName + ")";
+    }
+  }
+}
diff --git a/openapi/src/com/intellij/lang/cacheBuilder/WordsScanner.java b/openapi/src/com/intellij/lang/cacheBuilder/WordsScanner.java
new file mode 100644
index 000000000000..925a900e729c
--- /dev/null
+++ b/openapi/src/com/intellij/lang/cacheBuilder/WordsScanner.java
@@ -0,0 +1,14 @@
+package com.intellij.lang.cacheBuilder;
+
+import com.intellij.util.Processor;
+
+/**
+ * Created by IntelliJ IDEA.
+ * User: max
+ * Date: Jan 31, 2005
+ * Time: 9:07:44 PM
+ * To change this template use File | Settings | File Templates.
+ */
+public interface WordsScanner {
+  void processWords(CharSequence fileText, Processor<WordOccurence> processor);
+}
diff --git a/openapi/src/com/intellij/lang/folding/FoldingBuilder.java b/openapi/src/com/intellij/lang/folding/FoldingBuilder.java
new file mode 100644
index 000000000000..f78ee657eb40
--- /dev/null
+++ b/openapi/src/com/intellij/lang/folding/FoldingBuilder.java
@@ -0,0 +1,19 @@
+package com.intellij.lang.folding;
+
+import com.intellij.openapi.editor.Document;
+import com.intellij.psi.PsiElement;
+
+/**
+ * Created by IntelliJ IDEA.
+ * User: max
+ * Date: Feb 1, 2005
+ * Time: 12:10:19 AM
+ * To change this template use File | Settings | File Templates.
+ */
+public interface FoldingBuilder {
+  FoldingDescriptor[] buildFoldRegions(PsiElement file, Document document);
+
+  String getPlaceholderText(PsiElement elt);
+
+  boolean isCollapsedByDefault(PsiElement elt);
+}
diff --git a/openapi/src/com/intellij/lang/folding/FoldingDescriptor.java b/openapi/src/com/intellij/lang/folding/FoldingDescriptor.java
new file mode 100644
index 000000000000..3d128e12e9d8
--- /dev/null
+++ b/openapi/src/com/intellij/lang/folding/FoldingDescriptor.java
@@ -0,0 +1,29 @@
+package com.intellij.lang.folding;
+
+import com.intellij.openapi.util.TextRange;
+import com.intellij.psi.PsiElement;
+
+/**
+ * Created by IntelliJ IDEA.
+ * User: max
+ * Date: Feb 1, 2005
+ * Time: 12:14:17 AM
+ * To change this template use File | Settings | File Templates.
+ */
+public class FoldingDescriptor {
+  private PsiElement myElement;
+  private TextRange myRange;
+
+  public FoldingDescriptor(final PsiElement element, final TextRange range) {
+    myElement = element;
+    myRange = range;
+  }
+
+  public PsiElement getElement() {
+    return myElement;
+  }
+
+  public TextRange getRange() {
+    return myRange;
+  }
+}
diff --git a/source/com/intellij/codeInsight/folding/impl/FoldingPolicy.java b/source/com/intellij/codeInsight/folding/impl/FoldingPolicy.java
index 18c016fd548b..e895f03bf962 100644
--- a/source/com/intellij/codeInsight/folding/impl/FoldingPolicy.java
+++ b/source/com/intellij/codeInsight/folding/impl/FoldingPolicy.java
@@ -1,5 +1,9 @@
 package com.intellij.codeInsight.folding.impl;
 
+import com.intellij.lang.ASTNode;
+import com.intellij.lang.Language;
+import com.intellij.lang.folding.FoldingBuilder;
+import com.intellij.lang.folding.FoldingDescriptor;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.editor.Document;
 import com.intellij.openapi.progress.ProgressManager;
@@ -10,7 +14,6 @@ import com.intellij.psi.javadoc.PsiDocComment;
 import com.intellij.psi.util.PropertyUtil;
 import com.intellij.psi.xml.*;
 import com.intellij.uiDesigner.compiler.CodeGenerator;
-import com.intellij.lang.ASTNode;
 
 import java.util.*;
 
@@ -28,6 +31,18 @@ class FoldingPolicy {
                element1.getTextRange().getEndOffset() - element.getTextRange().getEndOffset();
       }
     });
+    final Language lang = file.getLanguage();
+    if (lang != null) {
+      final FoldingBuilder foldingBuilder = lang.getFoldingBuilder();
+      if (foldingBuilder != null) {
+        final FoldingDescriptor[] foldingDescriptors = foldingBuilder.buildFoldRegions(file, document);
+        for (int i = 0; i < foldingDescriptors.length; i++) {
+          FoldingDescriptor descriptor = foldingDescriptors[i];
+          map.put(descriptor.getElement(), descriptor.getRange());
+        }
+        return map;
+      }
+    }
 
     if (file instanceof PsiJavaFile) {
       PsiImportList importList = ((PsiJavaFile) file).getImportList();
@@ -242,6 +257,14 @@ class FoldingPolicy {
   }
 
   public static String getFoldingText(PsiElement element) {
+    final Language lang = element.getLanguage();
+    if (lang != null) {
+      final FoldingBuilder foldingBuilder = lang.getFoldingBuilder();
+      if (foldingBuilder != null) {
+        return foldingBuilder.getPlaceholderText(element);
+      }
+    }
+
     if (element instanceof PsiImportList) {
       return "...";
     } else if ( element instanceof PsiMethod && CodeGenerator.SETUP_METHOD_NAME.equals(((PsiMethod) element).getName()) ||
@@ -264,6 +287,14 @@ class FoldingPolicy {
 
 
   public static boolean isCollapseByDefault(PsiElement element) {
+    final Language lang = element.getLanguage();
+    if (lang != null) {
+      final FoldingBuilder foldingBuilder = lang.getFoldingBuilder();
+      if (foldingBuilder != null) {
+        return foldingBuilder.isCollapsedByDefault(element);
+      }
+    }
+
     CodeFoldingSettings settings = CodeFoldingSettings.getInstance();
     if (element instanceof PsiImportList) {
       return settings.COLLAPSE_IMPORTS;
diff --git a/source/com/intellij/psi/impl/cache/impl/idCache/IdTableBuilding.java b/source/com/intellij/psi/impl/cache/impl/idCache/IdTableBuilding.java
index 0774227cff06..b91636de014d 100644
--- a/source/com/intellij/psi/impl/cache/impl/idCache/IdTableBuilding.java
+++ b/source/com/intellij/psi/impl/cache/impl/idCache/IdTableBuilding.java
@@ -4,6 +4,9 @@ import com.intellij.aspects.lexer._AspectjLexer;
 import com.intellij.aspects.psi.PsiAspectFile;
 import com.intellij.ide.startup.FileContent;
 import com.intellij.ide.todo.TodoConfiguration;
+import com.intellij.lang.Language;
+import com.intellij.lang.cacheBuilder.WordOccurence;
+import com.intellij.lang.cacheBuilder.WordsScanner;
 import com.intellij.lexer.*;
 import com.intellij.openapi.diagnostic.Logger;
 import com.intellij.openapi.fileTypes.FileType;
@@ -11,7 +14,6 @@ import com.intellij.openapi.fileTypes.StdFileTypes;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.pom.java.LanguageLevel;
 import com.intellij.psi.*;
-import com.intellij.psi.xml.XmlFile;
 import com.intellij.psi.impl.PsiManagerImpl;
 import com.intellij.psi.impl.cache.impl.CacheManagerImpl;
 import com.intellij.psi.impl.source.parsing.jsp.JspStep1Lexer;
@@ -21,16 +23,18 @@ import com.intellij.psi.jsp.JspFile;
 import com.intellij.psi.search.TodoPattern;
 import com.intellij.psi.tree.IElementType;
 import com.intellij.psi.tree.java.IJavaElementType;
+import com.intellij.psi.xml.XmlFile;
 import com.intellij.uiDesigner.FormEditingUtil;
 import com.intellij.uiDesigner.compiler.Utils;
 import com.intellij.uiDesigner.lw.IComponent;
 import com.intellij.uiDesigner.lw.LwRootContainer;
+import com.intellij.util.Processor;
 import com.intellij.util.text.CharArrayCharSequence;
 import gnu.trove.TIntIntHashMap;
 
+import java.util.HashMap;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
-import java.util.HashMap;
 
 public class IdTableBuilding {
   private static final Logger LOG = Logger.getInstance("#com.intellij.psi.impl.cache.impl.idCache.IdTableBuilding");
@@ -217,9 +221,41 @@ public class IdTableBuilding {
       return cacheBuilders.get(StdFileTypes.XML);
     }
 
+    final Language lang = psiFile.getLanguage();
+    if (lang != null) {
+      final WordsScanner scanner = lang.getWordsScanner();
+      if (scanner != null) {
+        return new WordsScannerIdCacheBuilderAdapter(scanner);
+      }
+    }
+
     return null;
   }
 
+  private static class WordsScannerIdCacheBuilderAdapter implements IdCacheBuilder {
+    private WordsScanner myScanner;
+
+    public WordsScannerIdCacheBuilderAdapter(final WordsScanner scanner) {
+      myScanner = scanner;
+    }
+
+    public void build(char[] chars, int length, final TIntIntHashMap wordsTable, TodoPattern[] todoPatterns, int[] todoCounts) {
+      myScanner.processWords(new CharArrayCharSequence(chars, 0, length), new Processor<WordOccurence>() {
+        public boolean process(final WordOccurence t) {
+          IdCacheUtil.addOccurrence(wordsTable, t.getText().toString().hashCode(), convertToMask(t.getKind()));
+          return true;
+        }
+
+        private int convertToMask(final WordOccurence.Kind kind) {
+          if (kind == WordOccurence.Kind.CODE) return WordInfo.IN_CODE;
+          if (kind == WordOccurence.Kind.COMMENTS) return WordInfo.IN_COMMENTS;
+          if (kind == WordOccurence.Kind.LITERALS) return WordInfo.IN_STRING_LITERALS;
+          return 0;
+        }
+      });
+    }
+  }
+
   public static Result getBuildingRunnable(PsiManagerImpl manager, FileContent fileContent, final boolean buildTodos) {
     if (LOG.isDebugEnabled()){
       LOG.debug(
diff --git a/source/com/intellij/psi/impl/search/LowLevelSearchUtil.java b/source/com/intellij/psi/impl/search/LowLevelSearchUtil.java
index cb4124b974b6..07b2aaec3aee 100644
--- a/source/com/intellij/psi/impl/search/LowLevelSearchUtil.java
+++ b/source/com/intellij/psi/impl/search/LowLevelSearchUtil.java
@@ -1,5 +1,6 @@
 package com.intellij.psi.impl.search;
 
+import com.intellij.lang.ASTNode;
 import com.intellij.openapi.progress.ProgressIndicator;
 import com.intellij.openapi.progress.ProgressManager;
 import com.intellij.psi.PsiElement;
@@ -9,11 +10,9 @@ import com.intellij.psi.impl.source.parsing.ChameleonTransforming;
 import com.intellij.psi.impl.source.tree.ChameleonElement;
 import com.intellij.psi.impl.source.tree.CompositeElement;
 import com.intellij.psi.impl.source.tree.LeafElement;
-import com.intellij.psi.impl.source.tree.TreeElement;
 import com.intellij.psi.search.PsiElementProcessor;
 import com.intellij.psi.tree.TokenSet;
 import com.intellij.util.text.StringSearcher;
-import com.intellij.lang.ASTNode;
 
 import java.util.Set;
 
@@ -33,8 +32,8 @@ public class LowLevelSearchUtil {
                                                                 TokenSet elementTypes,
                                                                 ProgressIndicator progress) {
     ProgressManager.getInstance().checkCanceled();
-
-    if (elementTypes.isInSet(scope.getElementType())) {
+    final PsiElement scopePsi = SourceTreeToPsiMap.treeElementToPsi(scope);
+    if (elementTypes.isInSet(scope.getElementType()) || scopePsi.getLanguage() != null && scopePsi.getLanguage().mayHaveReferences(scope.getElementType())) {
       int startOffset;
       int endOffset;
       if (scope instanceof LeafElement) {
@@ -44,7 +43,7 @@ public class LowLevelSearchUtil {
         do {
           int i = leaf.searchWord(startOffset, searcher);
           if (i >= 0) {
-            if (!processor.execute(SourceTreeToPsiMap.treeElementToPsi(scope), i)) return false;
+            if (!processor.execute(scopePsi, i)) return false;
             startOffset = i + 1;
           }
           else {
@@ -76,7 +75,7 @@ public class LowLevelSearchUtil {
         do {
           int i = searchWord(buffer, startOffset, endOffset, searcher);
           if (i >= 0) {
-            if (!processor.execute(SourceTreeToPsiMap.treeElementToPsi(scope), i - originalStartOffset)) return false;
+            if (!processor.execute(scopePsi, i - originalStartOffset)) return false;
             startOffset = i + 1;
           }
           else {
@@ -99,40 +98,39 @@ public class LowLevelSearchUtil {
                                          PsiElementProcessorEx processor,
                                          TokenSet elementTypes,
                                          ProgressIndicator progress) {
-  synchronized (PsiLock.LOCK) {
-    ASTNode child = scope.getFirstChildNode();
-    while (child != null) {
-      if (child instanceof ChameleonElement) {
-        LeafElement leaf = (LeafElement)child;
-        if (leaf.searchWord(0, searcher) >= 0) {
-          ASTNode next = child.getTreeNext();
-          child = ChameleonTransforming.transform((ChameleonElement)child);
-          if (child == null) {
-            child = next;
+    synchronized (PsiLock.LOCK) {
+      ASTNode child = scope.getFirstChildNode();
+      while (child != null) {
+        if (child instanceof ChameleonElement) {
+          LeafElement leaf = (LeafElement)child;
+          if (leaf.searchWord(0, searcher) >= 0) {
+            ASTNode next = child.getTreeNext();
+            child = ChameleonTransforming.transform((ChameleonElement)child);
+            if (child == null) {
+              child = next;
+            }
+          continue;
           }
-        continue;
         }
+        child = child.getTreeNext();
       }
-      child = child.getTreeNext();
     }
-  }
 
-               ASTNode child = null;
-               while (true) {
-               synchronized (PsiLock.LOCK) {
-                 child = child != null ? child.getTreeNext() : scope.getFirstChildNode();
-                 while (child instanceof ChameleonElement) {
-                   child = child.getTreeNext();
-                 }
-                 if (child == null) break;
-               }
+    ASTNode child = null;
+    while (true) {
+      synchronized (PsiLock.LOCK) {
+        child = child != null ? child.getTreeNext() : scope.getFirstChildNode();
+        while (child instanceof ChameleonElement) {
+          child = child.getTreeNext();
+        }
+        if (child == null) break;
+      }
 
-             if (!processElementsContainingWordInElement(processor, (TreeElement)child, searcher, elementTypes,
-                                                         progress)) {
-               return false;
-             }
-               }
-               return true;
+      if (!processElementsContainingWordInElement(processor, child, searcher, elementTypes, progress)) {
+        return false;
+      }
+    }
+    return true;
   }
 
   public static int searchWord(char[] text, int startOffset, int endOffset, StringSearcher searcher) {
@@ -164,8 +162,7 @@ public class LowLevelSearchUtil {
     ASTNode scope,
     TokenSet elementTypes,
     Set namesSet,
-    ProgressIndicator progress
-    ) {
+    ProgressIndicator progress) {
     ProgressManager.getInstance().checkCanceled();
 
     if (elementTypes.isInSet(scope.getElementType())) {