WeakCache.h

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#ifndef G3D_WeakCache_h
#define G3D_WeakCache_h

#include "G3D/ReferenceCount.h"
#include "G3D/Table.h"

namespace G3D {

template<class Key, class ValueRef>
class WeakCache {
 typedef weak_ptr<typename ValueRef::element_type> ValueWeakRef;

private:

 Table<Key, ValueWeakRef> table;

public:
 ValueRef operator[](const Key& k) {
 if (table.containsKey(k)) {
 ValueWeakRef w = table[k];
 ValueRef s = w.lock();
 if (! s) {
 // This object has been collected; clean out its key
 table.remove(k);
 }
 return s;
 } else {
 return ValueRef();
 }
 }



 void getValues(Array<ValueRef>& values) {
 Array<Key> keys;
 table.getKeys(keys);
 for (int i = 0; i < keys.size(); ++i) {
 ValueRef value = (*this)[keys[i]];
 if(notNull(value)) {
 values.append(value);
 }
 }
 }

 void clear() {
 table.clear();
 }

 void set(const Key& k, ValueRef v) {
 table.set(k, v);
 }

 void remove(const Key& k) {
 if (table.containsKey(k)) {
 table.remove(k);
 }
 }
};

}
#endif