1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
|
/*******************************************************************************
* Copyright (c) 2008, 2013 IBM Corporation and others.
*
* This program and the accompanying materials
* are made available under the terms of the Eclipse Public License 2.0
* which accompanies this distribution, and is available at
* https://www.eclipse.org/legal/epl-2.0/
*
* SPDX-License-Identifier: EPL-2.0
*
* Contributors:
* IBM Corporation - initial API and implementation
*******************************************************************************/
package org.eclipse.equinox.internal.transforms;
import java.util.HashMap;
import org.eclipse.osgi.framework.log.FrameworkLogEntry;
import org.eclipse.osgi.internal.framework.EquinoxContainer;
import org.eclipse.osgi.internal.log.EquinoxLogServices;
import org.osgi.framework.*;
import org.osgi.util.tracker.ServiceTracker;
/**
* A dynamic list of transformers.
*/
public class TransformerList extends ServiceTracker<Object, Object> {
/**
* The stale state of this list. Set to true every time a new matching service instance is detected.
*/
private volatile boolean stale = true;
/**
* Local cache of transformers.
*/
private HashMap<String, StreamTransformer> transformers = new HashMap<String, StreamTransformer>();
private final EquinoxLogServices logServices;
/**
* Create a new instance of this list.
* @param context the context to track
* @throws InvalidSyntaxException thrown if there's an issue listening for changes to the given transformer type
*/
public TransformerList(BundleContext context, EquinoxLogServices logServices) throws InvalidSyntaxException {
super(context, context.createFilter("(&(objectClass=" //$NON-NLS-1$
+ Object.class.getName() + ")(" + TransformTuple.TRANSFORMER_TYPE //$NON-NLS-1$
+ "=*))"), null); //$NON-NLS-1$
this.logServices = logServices;
open();
}
/**
* Return the transformer of the given type being monitored by this list.
* If the list is stale it will first be rebuilt.
* @param type the type of transformer
* @return the transformer or null if no transformer of the given type is available.
*/
public synchronized StreamTransformer getTransformer(String type) {
if (stale) {
rebuildTransformersMap();
}
return transformers.get(type);
}
public synchronized boolean hasTransformers() {
if (stale) {
rebuildTransformersMap();
}
return transformers.size() > 0;
}
/**
* Consults the bundle context for services of the transformer type and builds the internal cache.
*/
private void rebuildTransformersMap() {
transformers.clear();
ServiceReference<Object>[] serviceReferences = getServiceReferences();
stale = false;
if (serviceReferences == null)
return;
for (int i = 0; i < serviceReferences.length; i++) {
ServiceReference<Object> serviceReference = serviceReferences[i];
String type = serviceReference.getProperty(TransformTuple.TRANSFORMER_TYPE).toString();
if (type == null || transformers.get(type) != null)
continue;
Object object = getService(serviceReference);
if (object instanceof StreamTransformer)
transformers.put(type, (StreamTransformer) object);
else {
ProxyStreamTransformer transformer;
try {
transformer = new ProxyStreamTransformer(object);
transformers.put(type, transformer);
} catch (SecurityException e) {
logServices.log(EquinoxContainer.NAME, FrameworkLogEntry.ERROR, "Problem creating transformer", e); //$NON-NLS-1$
} catch (NoSuchMethodException e) {
logServices.log(EquinoxContainer.NAME, FrameworkLogEntry.ERROR, "Problem creating transformer", e); //$NON-NLS-1$
}
}
}
}
public Object addingService(ServiceReference<Object> reference) {
try {
return super.addingService(reference);
} finally {
stale = true;
}
}
public void modifiedService(ServiceReference<Object> reference, Object service) {
super.modifiedService(reference, service);
stale = true;
}
public void removedService(ServiceReference<Object> reference, Object service) {
super.removedService(reference, service);
stale = true;
}
}
|
