1 files changed, 43 insertions, 0 deletions
diff --git a/src/library/scala/runtime/StructuralCallSite.java b/src/library/scala/runtime/StructuralCallSite.java
new file mode 100644
index 0000000000..f73b4f08e6
--- /dev/null
+++ b/src/library/scala/runtime/StructuralCallSite.java
@@ -0,0 +1,43 @@
+package scala.runtime;
+
+
+import java.lang.invoke.*;
+import java.lang.ref.SoftReference;
+import java.lang.reflect.Method;
+
+public final class StructuralCallSite {
+
+    private Class<?>[] parameterTypes;
+    private SoftReference<MethodCache> cache = new SoftReference<>(new EmptyMethodCache());
+
+    private StructuralCallSite(MethodType callType) {
+        parameterTypes = callType.parameterArray();
+    }
+
+    public MethodCache get() {
+        MethodCache cache = this.cache.get();
+        if (cache == null) {
+            cache = new EmptyMethodCache();
+            this.cache = new SoftReference<>(cache);
+        }
+        return cache;
+    }
+
+    public Method find(Class<?> receiver) {
+        return get().find(receiver);
+    }
+
+    public Method add(Class<?> receiver, Method m) {
+        cache = new SoftReference<MethodCache>(get().add(receiver, m));
+        return m;
+    }
+    public Class<?>[] parameterTypes() {
+        return parameterTypes;
+    }
+
+    public static CallSite bootstrap(MethodHandles.Lookup lookup, String invokedName,
+                                     MethodType invokedType, MethodType reflectiveCallType) throws Throwable {
+        StructuralCallSite structuralCallSite = new StructuralCallSite(reflectiveCallType);
+        return new ConstantCallSite(MethodHandles.constant(StructuralCallSite.class, structuralCallSite));
+    }
+}