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 * https://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.jexl342;
18
19 import org.apache.commons.jexl3.JexlEngine;
20 import org.apache.commons.jexl3.introspection.JexlPropertyGet;
21
22 /**
23 * Wraps a reference or optional property get executor.
24 */
25 public class ReferenceGetExecutor implements JexlPropertyGet {
26
27 /** The reference handler. */
28 private final ReferenceUberspect.ReferenceHandler handler;
29
30 /** The previous getter we did delegate to. */
31 private final JexlPropertyGet getter;
32
33 /**
34 * Creates an instance.
35 *
36 * @param referenceHandler the reference handler
37 * @param jexlGet the property getter
38 */
39 public ReferenceGetExecutor(final ReferenceUberspect.ReferenceHandler referenceHandler, final JexlPropertyGet jexlGet) {
40 if (referenceHandler == null || jexlGet == null) {
41 throw new IllegalArgumentException("handler and getter cant be null");
42 }
43 handler = referenceHandler;
44 getter = jexlGet;
45 }
46
47 /**
48 * Dereference an expected optional or reference.
49 *
50 * @param ref the reference
51 * @return the reference value or the reference
52 */
53 protected Object getReference(final Object ref) {
54 return handler.callGet(ref);
55 }
56
57 @Override
58 public Object invoke(final Object ref) throws Exception {
59 final Object obj = getReference(ref);
60 return getter.invoke(obj);
61 }
62
63 @Override
64 public boolean isCacheable() {
65 return getter.isCacheable();
66 }
67
68 @Override
69 public boolean tryFailed(final Object rval) {
70 return getter.tryFailed(rval);
71 }
72
73 @Override
74 public Object tryInvoke(final Object ref, final Object key) {
75 final Object obj = getReference(ref);
76 return obj == ref ? JexlEngine.TRY_FAILED : getter.tryInvoke(obj, key);
77 }
78 }