Test to verify issue #13

src/test/java/com/fluentinterface/examples/MapConstructor.java

@@ -0,0 +1,11 @@
+package com.fluentinterface.examples;
+
+import java.util.Map;
+
+public class MapConstructor {
+    public Map<String, Object> map;
+
+    public MapConstructor(Map<String, Object> map) {
+        this.map = map;
+    }
+}

src/test/java/com/fluentinterface/examples/MapConstructorBuilder.java

@@ -0,0 +1,16 @@
+package com.fluentinterface.examples;
+
+import com.fluentinterface.ReflectionBuilder;
+import com.fluentinterface.annotation.Constructs;
+import com.fluentinterface.builder.Builder;
+
+import java.util.Map;
+
+public interface MapConstructorBuilder extends Builder<MapConstructor> {
+    @Constructs
+    MapConstructorBuilder of(Map<String, Object> map);
+
+    static MapConstructorBuilder aMapConstructor() {
+        return ReflectionBuilder.implementationFor(MapConstructorBuilder.class).create();
+    }
+}

src/test/java/com/fluentinterface/examples/MapConstructorTest.java

@@ -0,0 +1,22 @@
+package com.fluentinterface.examples;
+
+import org.junit.Test;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import static com.fluentinterface.examples.MapConstructorBuilder.aMapConstructor;
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+public class MapConstructorTest {
+    @Test
+    public void instantiatesWithHashMap() {
+        Map<String, Object> map = new HashMap<>();
+        map.put("key", "value");
+
+        MapConstructor created = aMapConstructor().of(map).build();
+
+        assertThat(created.map.get("key"), is("value"));
+    }
+}