Method: maybeAs(Class)

1: /*
2: * *************************************************************************************************************************************************************
3: *
4: * TheseFoolishThings: Miscellaneous utilities
5: * http://tidalwave.it/projects/thesefoolishthings
6: *
7: * Copyright (C) 2009 - 2024 by Tidalwave s.a.s. (http://tidalwave.it)
8: *
9: * *************************************************************************************************************************************************************
10: *
11: * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License.
12: * You may obtain a copy of the License at
13: *
14: * http://www.apache.org/licenses/LICENSE-2.0
15: *
16: * 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
17: * CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.
18: *
19: * *************************************************************************************************************************************************************
20: *
21: * git clone https://bitbucket.org/tidalwave/thesefoolishthings-src
22: * git clone https://github.com/tidalwave-it/thesefoolishthings-src
23: *
24: * *************************************************************************************************************************************************************
25: */
26: package it.tidalwave.role.ui.impl;
27:
28: import javax.annotation.Nonnull;
29: import java.beans.PropertyChangeSupport;
30: import java.util.Collection;
31: import java.util.Optional;
32: import it.tidalwave.util.As;
33: import it.tidalwave.util.AsException;
34: import it.tidalwave.util.Callback;
35: import it.tidalwave.util.NamedCallback;
36: import it.tidalwave.role.ui.PresentationModel;
37: import lombok.ToString;
38: import lombok.experimental.Delegate;
39: import lombok.extern.slf4j.Slf4j;
40:
41: /***************************************************************************************************************************************************************
42: *
43: * A default implementation of {@link PresentationModel}.
44: *
45: * @author Fabrizio Giudici
46: *
47: **************************************************************************************************************************************************************/
48: @ToString(exclude = {"as", "pcs"}) @Slf4j
49: public class DefaultPresentationModel implements PresentationModel
50: {
51: @Nonnull
52: private final Object owner;
53:
54: @Delegate
55: private final PropertyChangeSupport pcs = new PropertyChangeSupport(this);
56:
57: private final As as;
58:
59: /***********************************************************************************************************************************************************
60: *
61: **********************************************************************************************************************************************************/
62: public DefaultPresentationModel (@Nonnull final Object owner, @Nonnull final Collection<Object> roles)
63: {
64: this.owner = owner;
65: as = As.forObject(owner, roles);
66: }
67:
68: /***********************************************************************************************************************************************************
69: * {@inheritDoc}
70: **********************************************************************************************************************************************************/
71: @Override @Nonnull
72: public <T> T as (@Nonnull final Class<? extends T> roleType)
73: {
74: return maybeAs(roleType).orElseThrow(() -> new AsException(roleType));
75: }
76:
77: /***********************************************************************************************************************************************************
78: * {@inheritDoc}
79: **********************************************************************************************************************************************************/
80: @SuppressWarnings("ConstantValue")
81: @Override @Nonnull
82: public <T> Optional<T> maybeAs (@Nonnull final Class<? extends T> roleType)
83: {
84: // Undocumented feature: for instance Zephyr needs to fire property events
85:• if (roleType.equals(PropertyChangeSupport.class))
86: {
87: return Optional.of(roleType.cast(pcs));
88: }
89:
90: final Optional<T> t = as.maybeAs(roleType);
91:
92:• if (t.isPresent())
93: {
94: return t;
95: }
96:
97:• if (owner instanceof As)
98: {
99: try
100: {
101: final var role = ((As)owner).as(roleType);
102:
103:• if (role != null) // do check it for improper implementations or partial mocks
104: {
105: return Optional.of(role);
106: }
107: }
108: catch (AsException ignore)
109: {
110: // fallback
111: }
112: }
113:
114: return Optional.empty();
115: }
116:
117: /***********************************************************************************************************************************************************
118: * {@inheritDoc}
119: **********************************************************************************************************************************************************/
120: @Override @Nonnull
121: public <T> Collection<T> asMany (@Nonnull final Class<? extends T> roleType)
122: {
123: final Collection<T> result = as.asMany(roleType);
124:
125: // The problem here is that we want only to add local roles in owner; but calling owner.as() will also
126: // find again the global roles that were discovered by AsSupport.
127: if (roleType.isAssignableFrom(owner.getClass()))
128: {
129: result.add(roleType.cast(owner));
130: }
131:
132: if (owner instanceof As)
133: {
134: result.addAll(((As)owner).asMany(roleType));
135: }
136:
137: return result;
138: }
139:
140: /***********************************************************************************************************************************************************
141: * {@inheritDoc}
142: **********************************************************************************************************************************************************/
143: @Override
144: public void dispose()
145: {
146: for (final var listener : pcs.getPropertyChangeListeners().clone())
147: {
148: pcs.removePropertyChangeListener(listener);
149: }
150:
151: asMany(NamedCallback.class).stream()
152: .filter(c -> c.getName().equals(CALLBACK_DISPOSE))
153: .forEach(callback -> wrap(callback, "While calling 'dispose' callbacks"));
154: }
155:
156: /***********************************************************************************************************************************************************
157: *
158: **********************************************************************************************************************************************************/
159: private static void wrap (@Nonnull final Callback callback, @Nonnull final String logMessage)
160: {
161: try
162: {
163: callback.call();
164: }
165: catch (Throwable t)
166: {
167: log.error(logMessage, t);
168: }
169: }
170: }