blob: ba3392795ac059835ee67ef5e98f7cd793fe2c94 (
plain)
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
|
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* 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 CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.tuscany.spi.implementation.impl;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.net.URL;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Enumeration;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.apache.tuscany.core.util.IOHelper;
public class Discovery {
/**
* Read the service name from a configuration file
*
* @param classLoader
* @param name The name of the service class
* @return A class name which extends/implements the service class
* @throws IOException
*/
private static Set<String> getServiceNames(ClassLoader classLoader, String name) throws IOException {
Set<String> set = new HashSet<String>();
Enumeration<URL> urls = classLoader.getResources("META-INF/services/" + name);
while (urls.hasMoreElements()) {
URL url = urls.nextElement();
Set<String> service = getServiceNames(url);
if (service != null) {
set.addAll(service);
}
}
return set;
}
private static Set<String> getServiceNames(URL url) throws IOException {
Set<String> names = new HashSet<String>();
InputStream is = IOHelper.getInputStream(url);
BufferedReader reader = null;
try {
reader = new BufferedReader(new InputStreamReader(is));
while (true) {
String line = reader.readLine();
if (line == null) {
break;
}
line = line.trim();
if (!line.startsWith("#") && !"".equals(line)) {
names.add(line.trim());
}
}
} finally {
if (reader != null) {
reader.close();
}
}
return names;
}
public static <T> Collection<T> getInstances(final ClassLoader classLoader, Class<T> serviceClass) {
List<T> instances = new ArrayList<T>();
try {
Set<String> services = getServiceNames(classLoader, serviceClass.getName());
for (String className : services) {
Class cls = Class.forName(className, true, classLoader);
instances.add(serviceClass.cast(cls.newInstance())); // NOPMD
}
} catch (Exception e) {
throw new IllegalStateException(e);
}
return instances;
}
}
|
