1 /*
   2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package jdk.nashorn.tools.jjs;
  27 
  28 import java.util.ArrayList;
  29 import java.util.Arrays;
  30 import java.util.Collections;
  31 import java.util.List;
  32 import java.util.WeakHashMap;
  33 import java.util.stream.Collectors;
  34 import jdk.nashorn.internal.runtime.JSType;
  35 import jdk.nashorn.internal.runtime.PropertyMap;
  36 import jdk.nashorn.internal.runtime.ScriptObject;
  37 import jdk.nashorn.internal.runtime.ScriptRuntime;
  38 import jdk.nashorn.internal.objects.NativeJava;
  39 
  40 /*
  41  * A helper class to get properties of a given object for source code completion.
  42  */
  43 final class PropertiesHelper {
  44     private PropertiesHelper() {}
  45 
  46     // cached properties list
  47     private static final WeakHashMap<Object, List<String>> propsCache = new WeakHashMap<>();
  48 
  49     // returns the list of properties of the given object
  50     static List<String> getProperties(final Object obj) {
  51         assert obj != null && obj != ScriptRuntime.UNDEFINED;
  52 
  53         if (JSType.isPrimitive(obj)) {
  54             return getProperties(JSType.toScriptObject(obj));
  55         }
  56 
  57         if (obj instanceof ScriptObject) {
  58             final ScriptObject sobj = (ScriptObject)obj;
  59             final PropertyMap pmap = sobj.getMap();
  60             if (propsCache.containsKey(pmap)) {
  61                 return propsCache.get(pmap);
  62             }
  63             final String[] keys = sobj.getAllKeys();
  64             List<String> props = Arrays.asList(keys);
  65             props = props.stream()
  66                          .filter(s -> Character.isJavaIdentifierStart(s.charAt(0)))
  67                          .collect(Collectors.toList());
  68             Collections.sort(props);
  69             // cache properties against the PropertyMap
  70             propsCache.put(pmap, props);
  71             return props;
  72         }
  73 
  74         if (NativeJava.isType(ScriptRuntime.UNDEFINED, obj)) {
  75             if (propsCache.containsKey(obj)) {
  76                 return propsCache.get(obj);
  77             }
  78             final List<String> props = NativeJava.getProperties(obj);
  79             Collections.sort(props);
  80             // cache properties against the StaticClass representing the class
  81             propsCache.put(obj, props);
  82             return props;
  83         }
  84 
  85         final Class<?> clazz = obj.getClass();
  86         if (propsCache.containsKey(clazz)) {
  87             return propsCache.get(clazz);
  88         }
  89 
  90         final List<String> props = NativeJava.getProperties(obj);
  91         Collections.sort(props);
  92         // cache properties against the Class object
  93         propsCache.put(clazz, props);
  94         return props;
  95     }
  96 
  97     // returns the list of properties of the given object that start with the given prefix
  98     static List<String> getProperties(final Object obj, final String prefix) {
  99         assert prefix != null && !prefix.isEmpty();
 100         return getProperties(obj).stream()
 101                    .filter(s -> s.startsWith(prefix))
 102                    .collect(Collectors.toList());
 103     }
 104 }