/*
* Licensed to Elasticsearch under one or more contributor
* license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright
* ownership. Elasticsearch licenses this file to you under
* the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.elasticsearch.script.javascript.support;
import org.mozilla.javascript.*;
import java.util.*;
/**
* Value Converter to marshal objects between Java and Javascript.
*
*
*/
public final class ScriptValueConverter {
private static final String TYPE_DATE = "Date";
/**
* Private constructor - methods are static
*/
private ScriptValueConverter() {
}
/**
* Convert an object from a script wrapper value to a serializable value valid outside
* of the Rhino script processor context.
* <p>
* This includes converting JavaScript Array objects to Lists of valid objects.
*
* @param value Value to convert from script wrapper object to external object value.
* @return unwrapped and converted value.
*/
public static Object unwrapValue(Object value) {
if (value == null) {
return null;
} else if (value instanceof Wrapper) {
// unwrap a Java object from a JavaScript wrapper
// recursively call this method to convert the unwrapped value
value = unwrapValue(((Wrapper) value).unwrap());
} else if (value instanceof IdScriptableObject) {
// check for special case Native object wrappers
String className = ((IdScriptableObject) value).getClassName();
// check for special case of the String object
if ("String".equals(className)) {
value = Context.jsToJava(value, String.class);
}
// check for special case of a Date object
else if ("Date".equals(className)) {
value = Context.jsToJava(value, Date.class);
} else {
// a scriptable object will probably indicate a multi-value property set
// set using a JavaScript associative Array object
Scriptable values = (Scriptable) value;
Object[] propIds = values.getIds();
// is it a JavaScript associative Array object using Integer indexes?
if (values instanceof NativeArray && isArray(propIds)) {
// convert JavaScript array of values to a List of Serializable objects
List<Object> propValues = new ArrayList<Object>(propIds.length);
for (int i = 0; i < propIds.length; i++) {
// work on each key in turn
Integer propId = (Integer) propIds[i];
// we are only interested in keys that indicate a list of values
if (propId instanceof Integer) {
// get the value out for the specified key
Object val = values.get(propId, values);
// recursively call this method to convert the value
propValues.add(unwrapValue(val));
}
}
value = propValues;
} else {
// any other JavaScript object that supports properties - convert to a Map of objects
Map<String, Object> propValues = new HashMap<String, Object>(propIds.length);
for (int i = 0; i < propIds.length; i++) {
// work on each key in turn
Object propId = propIds[i];
// we are only interested in keys that indicate a list of values
if (propId instanceof String) {
// get the value out for the specified key
Object val = values.get((String) propId, values);
// recursively call this method to convert the value
propValues.put((String) propId, unwrapValue(val));
}
}
value = propValues;
}
}
} else if (value instanceof Object[]) {
// convert back a list Object Java values
Object[] array = (Object[]) value;
ArrayList<Object> list = new ArrayList<Object>(array.length);
for (int i = 0; i < array.length; i++) {
list.add(unwrapValue(array[i]));
}
value = list;
} else if (value instanceof Map) {
// ensure each value in the Map is unwrapped (which may have been an unwrapped NativeMap!)
Map<Object, Object> map = (Map<Object, Object>) value;
Map<Object, Object> copyMap = new HashMap<Object, Object>(map.size());
for (Object key : map.keySet()) {
copyMap.put(key, unwrapValue(map.get(key)));
}
value = copyMap;
}
return value;
}
/**
* Convert an object from any repository serialized value to a valid script object.
* This includes converting Collection multi-value properties into JavaScript Array objects.
*
* @param scope Scripting scope
* @param value Property value
* @return Value safe for scripting usage
*/
public static Object wrapValue(Scriptable scope, Object value) {
// perform conversions from Java objects to JavaScript scriptable instances
if (value == null) {
return null;
} else if (value instanceof Date) {
// convert Date to JavaScript native Date object
// call the "Date" constructor on the root scope object - passing in the millisecond
// value from the Java date - this will construct a JavaScript Date with the same value
Date date = (Date) value;
value = ScriptRuntime.newObject(
Context.getCurrentContext(), scope, TYPE_DATE, new Object[]{date.getTime()});
} else if (value instanceof Collection) {
// recursively convert each value in the collection
Collection<Object> collection = (Collection<Object>) value;
Object[] array = new Object[collection.size()];
int index = 0;
for (Object obj : collection) {
array[index++] = wrapValue(scope, obj);
}
// convert array to a native JavaScript Array
value = Context.getCurrentContext().newArray(scope, array);
} else if (value instanceof Map) {
value = NativeMap.wrap(scope, (Map) value);
}
// simple numbers, strings and booleans are wrapped automatically by Rhino
return value;
}
/**
* Look at the id's of a native array and try to determine whether it's actually an Array or a Hashmap
*
* @param ids id's of the native array
* @return boolean true if it's an array, false otherwise (ie it's a map)
*/
private static boolean isArray(final Object[] ids) {
boolean result = true;
for (int i = 0; i < ids.length; i++) {
if (ids[i] instanceof Integer == false) {
result = false;
break;
}
}
return result;
}
}