1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.jexl3;
18
19 import java.util.concurrent.Callable;
20
21 /**
22 * Exposes a synchronized call to a script and synchronizes access to get/set methods.
23 */
24 public class SynchronizedContext extends MapContext implements JexlContext.AnnotationProcessor {
25 private final JexlContext context;
26
27 public SynchronizedContext(final JexlContext ctxt) {
28 this.context = ctxt;
29 }
30
31 /**
32 * Calls a script synchronized by an object monitor.
33 * @param var the object used for sync
34 * @param script the script
35 * @return the script value
36 */
37 public Object call(final Object var, final JexlScript script) {
38 final String[] parms = script.getParameters();
39 final boolean varisarg = parms != null && parms.length == 1;
40 if (var == null) {
41 return varisarg ? script.execute(context, var) : script.execute(context);
42 }
43 synchronized (var) {
44 return varisarg ? script.execute(context, var) : script.execute(context);
45 }
46 }
47
48 @Override
49 public Object get(final String name) {
50 synchronized (this) {
51 return super.get(name);
52 }
53 }
54
55 @Override
56 public Object processAnnotation(final String name, final Object[] args, final Callable<Object> statement) throws Exception {
57 if ("synchronized".equals(name)) {
58 final Object arg = args[0];
59 synchronized(arg) {
60 return statement.call();
61 }
62 }
63 throw new IllegalArgumentException("unknown annotation " + name);
64 }
65
66 @Override
67 public void set(final String name, final Object value) {
68 synchronized (this) {
69 super.set(name, value);
70 }
71 }
72
73 }