src/jdk.scripting.nashorn/share/classes/jdk/nashorn/internal/objects/NativeJava.java

*** 28,42 ****
--- 28,45 ----
  import static jdk.nashorn.internal.runtime.ECMAErrors.typeError;
  import static jdk.nashorn.internal.runtime.ScriptRuntime.UNDEFINED;
  
  import java.lang.invoke.MethodHandles;
  import java.lang.reflect.Array;
+ import java.util.ArrayList;
  import java.util.Collection;
+ import java.util.Collections;
  import java.util.Deque;
  import java.util.List;
  import java.util.Map;
  import java.util.Queue;
+ import jdk.internal.dynalink.beans.BeansLinker;
  import jdk.internal.dynalink.beans.StaticClass;
  import jdk.internal.dynalink.support.TypeUtilities;
  import jdk.nashorn.api.scripting.JSObject;
  import jdk.nashorn.api.scripting.ScriptObjectMirror;
  import jdk.nashorn.internal.objects.annotations.Attribute;
*** 441,450 ****
--- 444,494 ----
          }
  
          throw typeError("cant.convert.to.javascript.array", objArray.getClass().getName());
      }
  
+     /**
+      * Return properties of the given object. Properties also include "method names".
+      * This is meant for source code completion in interactive shells or editors.
+      *
+      * @param object the object whose properties are returned.
+      * @return list of properties
+      */
+     public static List<String> getProperties(Object object) {
+         if (object instanceof StaticClass) {
+             // static properties of the given class
+             final Class<?> clazz = ((StaticClass)object).getRepresentedClass();
+             final ArrayList<String> props = new ArrayList<>();
+             try {
+                 Bootstrap.checkReflectionAccess(clazz, true);
+                 // Usually writable properties are a subset as 'write-only' properties are rare
+                 props.addAll(BeansLinker.getReadableStaticPropertyNames(clazz));
+                 props.addAll(BeansLinker.getStaticMethodNames(clazz));
+             } catch (Exception ignored) {}
+             return props;
+         } else if (object instanceof JSObject) {
+             final JSObject jsObj = ((JSObject)object);
+             final ArrayList<String> props = new ArrayList<>();
+             props.addAll(jsObj.keySet());
+             return props;
+         } else if (object != null && object != UNDEFINED) {
+             // instance properties of the given object
+             final Class<?> clazz = object.getClass();
+             final ArrayList<String> props = new ArrayList<>();
+             try {
+                 Bootstrap.checkReflectionAccess(clazz, false);
+                 // Usually writable properties are a subset as 'write-only' properties are rare
+                 props.addAll(BeansLinker.getReadableInstancePropertyNames(clazz));
+                 props.addAll(BeansLinker.getInstanceMethodNames(clazz));
+             } catch (Exception ignored) {}
+             return props;
+         }
+ 
+         // don't know about that object
+         return Collections.<String>emptyList();
+     }
+ 
      private static int[] copyArray(final byte[] in) {
          final int[] out = new int[in.length];
          for(int i = 0; i < in.length; ++i) {
              out[i] = in[i];
          }