public Int2BooleanSortedMap subMap(final Integer from, final Integer to) {
   return new UnmodifiableSortedMap(sortedMap.subMap(from, to));
 }
 public Integer firstKey() {
   return sortedMap.firstKey();
 }
 public Integer lastKey() {
   return sortedMap.lastKey();
 }
 public int firstIntKey() {
   return sortedMap.firstIntKey();
 }
 public int lastIntKey() {
   return sortedMap.lastIntKey();
 }
 public ObjectSortedSet<Int2BooleanMap.Entry> int2BooleanEntrySet() {
   if (entries == null)
     entries = ObjectSortedSets.synchronize(sortedMap.int2BooleanEntrySet(), sync);
   return (ObjectSortedSet<Int2BooleanMap.Entry>) entries;
 }
 public IntSortedSet keySet() {
   if (keys == null) keys = IntSortedSets.unmodifiable(sortedMap.keySet());
   return (IntSortedSet) keys;
 }
 public Int2BooleanSortedMap tailMap(final Integer from) {
   return new SynchronizedSortedMap(sortedMap.tailMap(from), sync);
 }
 public IntComparator comparator() {
   return sortedMap.comparator();
 }
 public Int2BooleanSortedMap subMap(final Integer from, final Integer to) {
   return new SynchronizedSortedMap(sortedMap.subMap(from, to), sync);
 }
 public Int2BooleanSortedMap headMap(final Integer to) {
   return new SynchronizedSortedMap(sortedMap.headMap(to), sync);
 }
 public Integer lastKey() {
   synchronized (sync) {
     return sortedMap.lastKey();
   }
 }
 public int lastIntKey() {
   synchronized (sync) {
     return sortedMap.lastIntKey();
   }
 }
 public IntSortedSet keySet() {
   if (keys == null) keys = IntSortedSets.synchronize(sortedMap.keySet(), sync);
   return (IntSortedSet) keys;
 }
 public Int2BooleanSortedMap headMap(final Integer to) {
   return new UnmodifiableSortedMap(sortedMap.headMap(to));
 }
 public ObjectSortedSet<Int2BooleanMap.Entry> int2BooleanEntrySet() {
   if (entries == null) entries = ObjectSortedSets.unmodifiable(sortedMap.int2BooleanEntrySet());
   return (ObjectSortedSet<Int2BooleanMap.Entry>) entries;
 }
 public Int2BooleanSortedMap tailMap(final Integer from) {
   return new UnmodifiableSortedMap(sortedMap.tailMap(from));
 }
 public IntComparator comparator() {
   synchronized (sync) {
     return sortedMap.comparator();
   }
 }