package prefuse.util.collections;
/**
* Sorted map implementation using a red-black tree to map from float keys to
* int values.
*
* @author <a href="http://jheer.org">jeffrey heer</a>
*/
public class FloatIntTreeMap extends AbstractTreeMap implements FloatIntSortedMap {
// dummy entry used as wrapper for queries
private FloatEntry dummy =
new FloatEntry(Float.MIN_VALUE, Integer.MAX_VALUE, NIL, 0);
// ------------------------------------------------------------------------
// Constructors
public FloatIntTreeMap() {
this(null, false);
}
public FloatIntTreeMap(boolean allowDuplicates) {
this(null, allowDuplicates);
}
public FloatIntTreeMap(LiteralComparator comparator) {
this(comparator, false);
}
public FloatIntTreeMap(LiteralComparator comparator,
boolean allowDuplicates)
{
super(comparator, allowDuplicates);
}
// ------------------------------------------------------------------------
// SortedMap Methods
/**
* @see java.util.Map#clear()
*/
public void clear() {
++modCount;
size = 0;
root = NIL;
}
/**
* @see java.util.Map#containsKey(java.lang.Object)
*/
public boolean containsKey(float key) {
return find(key, 0) != NIL;
}
/**
* @see java.util.Map#get(java.lang.Object)
*/
public int get(float 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(float key, int value) {
Entry t = root;
lastOrder = 0;
if (t == NIL) {
incrementSize(true);
root = new FloatEntry(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 FloatEntry(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 FloatEntry(key, value, t, lastOrder);
fixUpInsert(t.right);
return Integer.MIN_VALUE;
}
}
}
}
/**
* @see java.util.Map#remove(java.lang.Object)
*/
public int remove(float 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(float key, int val) {
// remove the last instance with the given key
Entry x = findCeiling(key, 0);
if ( x!=NIL && x.getFloatKey() != key )
x = successor(x);
if (x==NIL || x.getFloatKey()!=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 float firstKey() {
return minimum(root).getFloatKey();
}
/**
* @see java.util.SortedMap#lastKey()
*/
public float lastKey() {
return maximum(root).getFloatKey();
}
// -- Collection view methods ---------------------------------------------
public LiteralIterator keyIterator() {
return new KeyIterator();
}
public LiteralIterator keyRangeIterator(float fromKey, boolean fromInc,
float toKey, boolean toInc)
{
Entry start, end;
if ( 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(float fromKey, boolean fromInc,
float 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) {
int c = cmp.compare(e1.getFloatKey(), e2.getFloatKey());
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(float key, int order) {
dummy.key = key;
dummy.order = order;
Entry e = find(dummy);
return e;
}
private Entry findPredecessor(float key, int order) {
dummy.key = key;
dummy.order = order;
Entry e = findPredecessor(dummy);
return e;
}
private Entry findCeiling(float key, int order) {
dummy.key = key;
dummy.order = order;
Entry e = findCeiling(dummy);
return e;
}
// ========================================================================
// Inner classes
// ------------------------------------------------------------------------
// Entry class - represents a Red-Black Tree Node
static class FloatEntry extends AbstractTreeMap.Entry {
float key;
public FloatEntry(float key, int val) {
super(val);
this.key = key;
}
public FloatEntry(float key, int val, Entry parent, int order) {
super(val, parent, order);
this.key = key;
}
public float getFloatKey() {
return key;
}
public Object getKey() {
return new Float(key);
}
public boolean keyEquals(Entry e) {
return (e instanceof FloatEntry && key == ((FloatEntry)e).key);
}
public boolean equals(Object o) {
if (!(o instanceof FloatEntry))
return false;
FloatEntry e = (FloatEntry)o;
return (key == e.key && val == e.val);
}
public int hashCode() {
int khash = Float.floatToIntBits(key);
int vhash = val;
return khash ^ vhash ^ order;
}
public String toString() {
return key + "=" + val;
}
public void copyFields(Entry x) {
super.copyFields(x);
this.key = x.getFloatKey();
}
}
// ------------------------------------------------------------------------
// Iterators
private class KeyIterator extends AbstractTreeMap.KeyIterator {
public KeyIterator() {
super();
}
public KeyIterator(Entry start, Entry end) {
super(start, end);
}
public boolean isFloatSupported() {
return true;
}
public float nextFloat() {
return nextEntry().getFloatKey();
}
}
} // end of class FloatIntTreeMap