package prefuse.util.collections;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
/**
* Sorted map implementation using a red-black tree to map from Object keys to
* int values.
*
* @author <a href="http://jheer.org">jeffrey heer</a>
*/
public class ObjectIntTreeMap extends AbstractTreeMap
implements ObjectIntSortedMap
{
// dummy entry used as wrapper for queries
private ObjectEntry dummy = new ObjectEntry(null, Integer.MIN_VALUE, NIL, 0);
private Comparator cmp = null;
// ------------------------------------------------------------------------
// Constructors
public ObjectIntTreeMap() {
this(null, false);
}
public ObjectIntTreeMap(boolean allowDuplicates) {
this(null, allowDuplicates);
}
public ObjectIntTreeMap(Comparator comparator) {
this(comparator, false);
}
public ObjectIntTreeMap(Comparator comparator, boolean allowDuplicates) {
super(null, allowDuplicates);
this.cmp = (comparator == null ? super.comparator() : comparator);
}
/**
* @see java.util.SortedMap#comparator()
*/
public Comparator comparator() {
return cmp;
}
// ------------------------------------------------------------------------
// SortedMap Methods
/**
* @see java.util.Map#containsKey(java.lang.Object)
*/
public boolean containsKey(Object key) {
return find(key, 0) != NIL;
}
/**
* @see java.util.Map#get(java.lang.Object)
*/
public int get(Object key) {
Entry ret = find(key, 0);
return ( ret == NIL ? Integer.MIN_VALUE : ret.val );
}
/**
* @see java.util.Map#put(java.lang.Object, java.lang.Object)
*/
public int put(Object key, int value) {
Entry t = root;
lastOrder = 0;
if (t == NIL) {
incrementSize(true);
root = new ObjectEntry(key, value, NIL, lastOrder);
return Integer.MIN_VALUE;
}
dummy.key = key;
dummy.order = Integer.MAX_VALUE;
while (true) {
int cmp = compare(dummy, t);
if (cmp == 0) {
return t.setValue(value);
} else if (cmp < 0) {
if (t.left != NIL) {
t = t.left;
} else {
incrementSize(lastOrder==0);
t.left = new ObjectEntry(key, value, t, lastOrder);
fixUpInsert(t.left);
return Integer.MIN_VALUE;
}
} else { // cmp > 0
if (t.right != NIL) {
t = t.right;
} else {
incrementSize(lastOrder==0);
t.right = new ObjectEntry(key, value, t, lastOrder);
fixUpInsert(t.right);
return Integer.MIN_VALUE;
}
}
}
}
/**
* @see java.util.Map#remove(java.lang.Object)
*/
public int remove(Object key) {
// remove the last instance with the given key
Entry x;
if ( allowDuplicates )
x = findPredecessor(key, Integer.MAX_VALUE);
else
x = find(key, 0);
if (x == NIL)
return Integer.MIN_VALUE;
int val = x.val;
remove(x);
return val;
}
public int remove(Object key, int val) {
// remove the last instance with the given key
Entry x = findCeiling(key, 0);
if ( x!=NIL && ((key==null && x.getKey()!=null) ||
(key!=null && !x.getKey().equals(key))) )
x = successor(x);
if (x==NIL || ((key==null && x.getKey()!=null)
|| (key!=null && !x.getKey().equals(key))) )
return Integer.MIN_VALUE;
for ( ; x.val != val && x != NIL; x = successor(x) );
if (x == NIL) return Integer.MIN_VALUE;
remove(x);
return val;
}
/**
* @see java.util.SortedMap#firstKey()
*/
public Object firstKey() {
return minimum(root).getKey();
}
/**
* @see java.util.SortedMap#lastKey()
*/
public Object lastKey() {
return maximum(root).getKey();
}
// -- Collection view methods ---------------------------------------------
public Iterator keyIterator() {
return new KeyIterator();
}
public Iterator keyRangeIterator(Object fromKey, boolean fromInc,
Object toKey, boolean toInc)
{
Entry start, end;
if ( fromKey == toKey && (fromKey == MIN_KEY || fromKey == MAX_KEY) )
return Collections.EMPTY_LIST.iterator();
boolean bmin = (fromKey == MIN_KEY || toKey == MAX_KEY);
boolean bmax = (fromKey == MAX_KEY || toKey == MIN_KEY);
if ( !bmax && (bmin || cmp.compare(fromKey, toKey) <= 0) ) {
start = findCeiling(fromKey, (fromInc ? 0 : Integer.MAX_VALUE));
end = findCeiling(toKey, (toInc? Integer.MAX_VALUE : 0));
} else {
start = findCeiling(fromKey, (fromInc ? Integer.MAX_VALUE : 0));
start = predecessor(start);
end = findCeiling(toKey, (toInc ? 0 : Integer.MAX_VALUE));
end = predecessor(end);
}
return new KeyIterator(start, end);
}
public IntIterator valueRangeIterator(Object fromKey, boolean fromInc,
Object toKey, boolean toInc)
{
return new ValueIterator(
(EntryIterator)keyRangeIterator(fromKey,fromInc,toKey,toInc));
}
// ------------------------------------------------------------------------
// Internal Binary Search Tree / Red-Black Tree methods
// Adapted from Cormen, Leiserson, and Rivest's Introduction to Algorithms
protected int compare(Entry e1, Entry e2) {
Object k1 = e1.getKey(), k2 = e2.getKey();
if ( k1 == k2 && (k1 == MIN_KEY || k1 == MAX_KEY) ) {
return 0;
} else if ( k1 == MIN_KEY || k2 == MAX_KEY ) {
return -1;
} else if ( k1 == MAX_KEY || k2 == MIN_KEY ) {
return 1;
}
int c = cmp.compare(e1.getKey(), e2.getKey());
if ( allowDuplicates ) {
if ( c == 0 ) {
c = (e1.order < e2.order ? -1 : (e1.order > e2.order ? 1 : 0));
lastOrder = 1 + (c < 0 ? e1.order : e2.order);
}
}
return c;
}
private Entry find(Object key, int order) {
dummy.key = key;
dummy.order = order;
Entry e = find(dummy);
dummy.key = null;
return e;
}
private Entry findPredecessor(Object key, int order) {
dummy.key = key;
dummy.order = order;
Entry e = findPredecessor(dummy);
dummy.key = null;
return e;
}
private Entry findCeiling(Object key, int order) {
dummy.key = key;
dummy.order = order;
Entry e = findCeiling(dummy);
dummy.key = null;
return e;
}
// ========================================================================
// Inner classes
// ------------------------------------------------------------------------
// Entry class - represents a Red-Black Tree Node
static class ObjectEntry extends AbstractTreeMap.Entry {
Object key;
public ObjectEntry(Object key, int val) {
super(val);
this.key = key;
}
public ObjectEntry(Object key, int val, Entry parent, int order) {
super(val, parent, order);
this.key = key;
}
public Object getKey() {
return key;
}
public void copyFields(Entry x) {
super.copyFields(x);
this.key = x.getKey();
}
}
} // end of class DuplicateTreeMap