Map -> iterable transformer

2 files changed, 83 insertions, 0 deletions

diff --git a/model-data/src/main/java/org/eclipse/viatra/solver/data/map/CursorAsIterator.java b/model-data/src/main/java/org/eclipse/viatra/solver/data/map/CursorAsIterator.java
new file mode 100644
index 00000000..b29b3119
--- /dev/null
+++ b/model-data/src/main/java/org/eclipse/viatra/solver/data/map/CursorAsIterator.java
@@ -0,0 +1,57 @@
+package org.eclipse.viatra.solver.data.map;
+
+import java.util.Iterator;
+import java.util.NoSuchElementException;
+import java.util.function.BiFunction;
+import java.util.function.BiPredicate;
+
+public class CursorAsIterator<K,V,D> implements Iterator<D> {
+        private final Cursor<K, V> internal;
+        private final BiFunction<K, V, D> entryTransformation;
+        private final BiPredicate<K,V> filtering;
+        
+        D lastValidElement;
+        
+        public CursorAsIterator(Cursor<K, V> internal, BiFunction<K, V, D> entryTransformation, BiPredicate<K,V> filtering) {
+                this.internal = internal;
+                this.entryTransformation = entryTransformation;
+                this.filtering = filtering;
+                
+                moveToNext();
+        }
+        public CursorAsIterator(Cursor<K, V> internal, BiFunction<K, V, D> entryTransformation) {
+                this.internal = internal;
+                this.entryTransformation = entryTransformation;
+                this.filtering = ((k,v)->true);
+                
+                moveToNext();
+        }
+        
+        private void moveToNext() {
+                internal.move();
+                while(!internal.isTerminated() && !filtering.test(internal.getKey(), internal.getValue())) {
+                        internal.move();
+                }
+                if(!internal.isTerminated()) {
+                        lastValidElement = entryTransformation.apply(internal.getKey(), internal.getValue());
+                }
+        }
+        
+        
+        @Override
+        public boolean hasNext() {
+                return !internal.isTerminated();
+        }
+        @Override
+        public D next() {
+                if(hasNext()) {
+                        D last = lastValidElement;
+                        moveToNext();
+                        return last;
+                } else {
+                        throw new NoSuchElementException();
+                }
+
+        }
+        
+}
diff --git a/model-data/src/main/java/org/eclipse/viatra/solver/data/map/MapAsIterable.java b/model-data/src/main/java/org/eclipse/viatra/solver/data/map/MapAsIterable.java
new file mode 100644
index 00000000..22b5e6c1
--- /dev/null
+++ b/model-data/src/main/java/org/eclipse/viatra/solver/data/map/MapAsIterable.java
@@ -0,0 +1,26 @@
+package org.eclipse.viatra.solver.data.map;
+
+import java.util.Iterator;
+import java.util.function.BiFunction;
+import java.util.function.BiPredicate;
+
+public class MapAsIterable<K,V,D> implements Iterable<D> {
+        private final VersionedMap<K, V> internal;
+        private final BiFunction<K, V, D> entryTransformation;
+        private final BiPredicate<K,V> filtering;
+        
+        public MapAsIterable(VersionedMap<K, V> internal, BiFunction<K, V, D> entryTransformation, BiPredicate<K,V> filtering) {
+                this.internal = internal;
+                this.entryTransformation = entryTransformation;
+                this.filtering = filtering;
+        }
+        public MapAsIterable(VersionedMap<K, V> internal, BiFunction<K, V, D> entryTransformation) {
+                this.internal = internal;
+                this.entryTransformation = entryTransformation;
+                this.filtering = ((k,v)->true);
+        }
+        @Override
+        public Iterator<D> iterator() {
+                return new CursorAsIterator<>(internal.getAll(), entryTransformation, filtering);
+        }
+}