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.scxml2.env;
18
19 import java.io.Serializable;
20 import java.util.AbstractMap;
21 import java.util.HashSet;
22 import java.util.Set;
23
24 import org.apache.commons.scxml2.Context;
25
26 /**
27 * A map that will back the effective {@link Context} for an {@link org.apache.commons.scxml2.Evaluator} execution.
28 * The effective context enables the chaining of contexts all the way from the current state node to the root.
29 */
30 public final class EffectiveContextMap extends AbstractMap<String, Object> implements Serializable {
31
32 private static final long serialVersionUID = 1L;
33
34 /** The {@link org.apache.commons.scxml2.Context} for the current state. */
35 private final Context leaf;
36
37 /** Constructor. */
38 public EffectiveContextMap(final Context ctx) {
39 super();
40 this.leaf = ctx;
41 }
42
43 /**
44 * {@inheritDoc}
45 */
46 @Override
47 public Set<Entry<String, Object>> entrySet() {
48 Set<Entry<String, Object>> entrySet = new HashSet<Entry<String, Object>>();
49 Context current = leaf;
50 while (current != null) {
51 entrySet.addAll(current.getVars().entrySet());
52 current = current.getParent();
53 }
54 return entrySet;
55 }
56
57 /**
58 * {@inheritDoc}
59 */
60 @Override
61 public Object put(final String key, final Object value) {
62 Object old = leaf.get(key);
63 if (leaf.has(key)) {
64 leaf.set(key, value);
65 } else {
66 leaf.setLocal(key, value);
67 }
68 return old;
69 }
70
71 /**
72 * {@inheritDoc}
73 */
74 @Override
75 public Object get(final Object key) {
76 if (key != null) {
77 Context current = leaf;
78 while (current != null) {
79 if (current.getVars().containsKey(key.toString())) {
80 return current.getVars().get(key);
81 }
82 current = current.getParent();
83 }
84 }
85 return null;
86 }
87 }