Added class for useful iterator functions (motivated by GUAVA)

1 files changed, 29 insertions, 0 deletions

diff --git a/model-data/src/main/java/org/eclipse/viatra/solver/data/util/CollectionsUtil.java b/model-data/src/main/java/org/eclipse/viatra/solver/data/util/CollectionsUtil.java
new file mode 100644
index 00000000..d950228d
--- /dev/null
+++ b/model-data/src/main/java/org/eclipse/viatra/solver/data/util/CollectionsUtil.java
@@ -0,0 +1,29 @@
+package org.eclipse.viatra.solver.data.util;
+
+import java.util.Iterator;
+import java.util.function.Function;
+
+public final class CollectionsUtil {
+        private CollectionsUtil() {
+                throw new UnsupportedOperationException();
+        }
+        
+        static <S,T> Iterator<T> map(Iterator<S> source, Function<S, T> transformation) {
+                return new Iterator<T>() {
+
+                        @Override
+                        public boolean hasNext() {
+                                return source.hasNext();
+                        }
+
+                        @Override
+                        public T next() {
+                                return transformation.apply(source.next());
+                        }
+                };
+        }
+        
+        static <S,T> Iterable<T> map(Iterable<S> source, Function<S, T> transformation) {
+                return (()->map(source.iterator(),transformation));
+        }
+}