--- /dev/null
+package org.argeo.api.acr;
+
+import java.util.Map;
+
+/** A hierarchical structure of unnamed mappings. */
+public interface StructuredData<KEY, VALUE, CHILD> extends Map<KEY, VALUE>, Iterable<CHILD> {
+ /*
+ * DEFAULT METHODS
+ */
+ default <A> A adapt(Class<A> clss) {
+ throw new UnsupportedOperationException("Cannot adapt content " + this + " to " + clss.getName());
+ }
+}