diff --git a/platform/core-impl/src/com/intellij/util/DocumentUtil.java b/platform/core-impl/src/com/intellij/util/DocumentUtil.java
index 2218db336744..1d62a3149dfb 100644
--- a/platform/core-impl/src/com/intellij/util/DocumentUtil.java
+++ b/platform/core-impl/src/com/intellij/util/DocumentUtil.java
@@ -133,4 +133,14 @@ public final class DocumentUtil {
   public static int getNextCodePointOffset(@NotNull Document document, int offset) {
     return offset + (isSurrogatePair(document, offset) ? 2 : 1);
   }
+
+  public static boolean isLineEmpty(@NotNull Document document, final int line) {
+    final CharSequence chars = document.getCharsSequence();
+    int start = document.getLineStartOffset(line);
+    int end = Math.min(document.getLineEndOffset(line), document.getTextLength() - 1);
+    for (int i = start; i <= end; i++) {
+      if (!Character.isWhitespace(chars.charAt(i))) return false;
+    }
+    return true;
+  }
 }
diff --git a/platform/lang-impl/src/com/intellij/codeInsight/generation/CommentByLineCommentHandler.java b/platform/lang-impl/src/com/intellij/codeInsight/generation/CommentByLineCommentHandler.java
index 9f54c79003b8..1f0d05eaf3d1 100644
--- a/platform/lang-impl/src/com/intellij/codeInsight/generation/CommentByLineCommentHandler.java
+++ b/platform/lang-impl/src/com/intellij/codeInsight/generation/CommentByLineCommentHandler.java
@@ -119,7 +119,7 @@ public class CommentByLineCommentHandler extends MultiCaretCodeInsightActionHand
                                  startOffset == document.getLineStartOffset(document.getLineNumber(startOffset)) &&
                                  endOffset == document.getLineEndOffset(document.getLineNumber(endOffset - 1)) + 1;
     boolean startingNewLineComment = !hasSelection
-                                     && isLineEmpty(document, document.getLineNumber(startOffset))
+                                     && DocumentUtil.isLineEmpty(document, document.getLineNumber(startOffset))
                                      && !Comparing.equal(IdeActions.ACTION_COMMENT_LINE,
                                                          ActionManagerEx.getInstanceEx().getPrevPreformedActionId());
     currentBlock.caretUpdate = startingNewLineComment ? CaretUpdate.PUT_AT_COMMENT_START :
@@ -172,7 +172,7 @@ public class CommentByLineCommentHandler extends MultiCaretCodeInsightActionHand
         }
 
         block.commenters[line - startLine] = commenter;
-        if (!isLineCommented(block, line, commenter) && (singleline || !isLineEmpty(document, line))) {
+        if (!isLineCommented(block, line, commenter) && (singleline || !DocumentUtil.isLineEmpty(document, line))) {
           allLinesCommented = false;
           if (commenter instanceof IndentedCommenter) {
             final Boolean value = ((IndentedCommenter)commenter).forceIndentedLineComment();
@@ -306,16 +306,6 @@ public class CommentByLineCommentHandler extends MultiCaretCodeInsightActionHand
     return blockSuitableCommenter;
   }
 
-  private static boolean isLineEmpty(Document document, final int line) {
-    final CharSequence chars = document.getCharsSequence();
-    int start = document.getLineStartOffset(line);
-    int end = Math.min(document.getLineEndOffset(line), document.getTextLength() - 1);
-    for (int i = start; i <= end; i++) {
-      if (!Character.isWhitespace(chars.charAt(i))) return false;
-    }
-    return true;
-  }
-
   private static boolean isLineCommented(Block block, final int line, final Commenter commenter) {
     boolean commented;
     int lineEndForBlockCommenting = -1;
diff --git a/platform/platform-impl/src/com/intellij/openapi/editor/actions/BackwardParagraphAction.java b/platform/platform-impl/src/com/intellij/openapi/editor/actions/BackwardParagraphAction.java
index 3c52a0c39737..2fcf6f110fb8 100644
--- a/platform/platform-impl/src/com/intellij/openapi/editor/actions/BackwardParagraphAction.java
+++ b/platform/platform-impl/src/com/intellij/openapi/editor/actions/BackwardParagraphAction.java
@@ -7,10 +7,11 @@ import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.editor.EditorModificationUtil;
 import com.intellij.openapi.editor.actionSystem.EditorAction;
 import com.intellij.openapi.editor.actionSystem.EditorActionHandler;
-import com.intellij.openapi.util.text.StringUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import static com.intellij.util.DocumentUtil.isLineEmpty;
+
 /**
  * Emulates Emacs 'backward-paragraph' action
  */
@@ -62,10 +63,5 @@ public class BackwardParagraphAction extends EditorAction {
       caret.moveToOffset(targetOffset);
       EditorModificationUtil.scrollToCaret(editor);
     }
-
-    private static boolean isLineEmpty(Document document, int line) {
-      return StringUtil.equalsIgnoreWhitespaces(
-        document.getImmutableCharSequence().subSequence(document.getLineStartOffset(line), document.getLineEndOffset(line)), "");
-    }
   }
 }
diff --git a/platform/platform-impl/src/com/intellij/openapi/editor/actions/ForwardParagraphAction.java b/platform/platform-impl/src/com/intellij/openapi/editor/actions/ForwardParagraphAction.java
index ee91a1dc1f5b..5b162d02d30f 100644
--- a/platform/platform-impl/src/com/intellij/openapi/editor/actions/ForwardParagraphAction.java
+++ b/platform/platform-impl/src/com/intellij/openapi/editor/actions/ForwardParagraphAction.java
@@ -7,10 +7,11 @@ import com.intellij.openapi.editor.Editor;
 import com.intellij.openapi.editor.EditorModificationUtil;
 import com.intellij.openapi.editor.actionSystem.EditorAction;
 import com.intellij.openapi.editor.actionSystem.EditorActionHandler;
-import com.intellij.openapi.util.text.StringUtil;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+import static com.intellij.util.DocumentUtil.isLineEmpty;
+
 /**
  * Emulates Emacs 'forward-paragraph' action
  */
@@ -52,10 +53,5 @@ public class ForwardParagraphAction extends EditorAction {
       caret.moveToOffset(targetOffset);
       EditorModificationUtil.scrollToCaret(editor);
     }
-
-    private static boolean isLineEmpty(Document document, int line) {
-      return StringUtil.equalsIgnoreWhitespaces(
-        document.getImmutableCharSequence().subSequence(document.getLineStartOffset(line), document.getLineEndOffset(line)), "");
-    }
   }
 }