diff --git a/src/org/geometerplus/android/fbreader/libraryService/Util.java b/src/org/geometerplus/android/fbreader/libraryService/Util.java
index aba64efc3..ba5b86b76 100644
--- a/src/org/geometerplus/android/fbreader/libraryService/Util.java
+++ b/src/org/geometerplus/android/fbreader/libraryService/Util.java
@@ -19,13 +19,10 @@
 
 package org.geometerplus.android.fbreader.libraryService;
 
-import java.util.Arrays;
-import java.util.List;
-
 import org.geometerplus.fbreader.book.Author;
 import org.geometerplus.fbreader.book.Tag;
 
-public abstract class Util {
+abstract class Util {
 	static String authorToString(Author author) {
 		return new StringBuilder(author.DisplayName).append('\000').append(author.SortKey).toString();
 	}
@@ -51,8 +48,4 @@ public abstract class Util {
 			return Tag.NULL;
 		}
 	}
-
-	public static List<String> splitDirectories(String value) {
-		return Arrays.asList(value.split(";"));
-	}
 }
diff --git a/src/org/geometerplus/fbreader/Paths.java b/src/org/geometerplus/fbreader/Paths.java
index d8eeffd8a..2e57c42c5 100644
--- a/src/org/geometerplus/fbreader/Paths.java
+++ b/src/org/geometerplus/fbreader/Paths.java
@@ -23,7 +23,6 @@ import java.util.List;
 
 import android.os.Environment;
 
-import org.geometerplus.android.fbreader.libraryService.Util;
 import org.geometerplus.zlibrary.core.options.ZLStringOption;
 import org.geometerplus.zlibrary.core.options.ZLStringListOption;
 
diff --git a/src/org/geometerplus/fbreader/library/FileFirstLevelTree.java b/src/org/geometerplus/fbreader/library/FileFirstLevelTree.java
index 06b58e489..468d78250 100644
--- a/src/org/geometerplus/fbreader/library/FileFirstLevelTree.java
+++ b/src/org/geometerplus/fbreader/library/FileFirstLevelTree.java
@@ -19,13 +19,10 @@
 
 package org.geometerplus.fbreader.library;
 
-import java.util.List;
-
 import org.geometerplus.zlibrary.core.resources.ZLResource;
 import org.geometerplus.zlibrary.core.filesystem.ZLFile;
 
 import org.geometerplus.fbreader.Paths;
-import org.geometerplus.android.fbreader.libraryService.Util;
 
 public class FileFirstLevelTree extends FirstLevelTree {
 	FileFirstLevelTree(RootTree root) {
diff --git a/src/org/geometerplus/fbreader/library/FileTree.java b/src/org/geometerplus/fbreader/library/FileTree.java
index d90c3008b..3dac39e28 100644
--- a/src/org/geometerplus/fbreader/library/FileTree.java
+++ b/src/org/geometerplus/fbreader/library/FileTree.java
@@ -100,6 +100,9 @@ public class FileTree extends LibraryTree {
 	public Book getBook() {
 		if (myBook == null) {
 			myBook = Collection.getBookByFile(myFile);
+			if (myBook == null) {
+				myBook = NULL_BOOK;
+			}
 		}
 		return myBook instanceof Book ? (Book)myBook : null;
 	}
diff --git a/src/org/geometerplus/fbreader/library/FirstLevelTree.java b/src/org/geometerplus/fbreader/library/FirstLevelTree.java
index 0ec61ee61..a98b54ec2 100644
--- a/src/org/geometerplus/fbreader/library/FirstLevelTree.java
+++ b/src/org/geometerplus/fbreader/library/FirstLevelTree.java
@@ -21,17 +21,17 @@ package org.geometerplus.fbreader.library;
 
 import org.geometerplus.zlibrary.core.resources.ZLResource;
 
-class FirstLevelTree extends LibraryTree {
+abstract class FirstLevelTree extends LibraryTree {
 	private final String myId;
 	private final ZLResource myResource;
 
-	FirstLevelTree(LibraryTree root, int position, String id) {
+	FirstLevelTree(RootTree root, int position, String id) {
 		super(root, position);
 		myId = id;
 		myResource = resource().getResource(myId);
 	}
 
-	FirstLevelTree(LibraryTree root, String id) {
+	FirstLevelTree(RootTree root, String id) {
 		super(root);
 		myId = id;
 		myResource = resource().getResource(myId);
diff --git a/src/org/geometerplus/fbreader/library/LibraryTree.java b/src/org/geometerplus/fbreader/library/LibraryTree.java
index d307adebf..3072e087a 100644
--- a/src/org/geometerplus/fbreader/library/LibraryTree.java
+++ b/src/org/geometerplus/fbreader/library/LibraryTree.java
@@ -41,7 +41,6 @@ public abstract class LibraryTree extends FBTree {
 	static final String ROOT_BY_SERIES = "bySeries";
 	static final String ROOT_BY_TAG = "byTag";
 	static final String ROOT_FILE_TREE = "fileTree";
-	static final String NODE_LIBRARY_DIRECTORY = "fileTreeLibrary";
 
 	protected LibraryTree(IBookCollection collection) {
 		super();