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Version 2.1 by christoph_lechleitner@iteg_at on 2013-07-09 02.55:43
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1 = {{id name="Multi-DataSourcepoolingwithJDBC-Provider-Introduction"/}}Introduction =
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3 Many OSGi bundles require a pool of database connections, and usually the implementing it themselfes.
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5 In larger multi-package projects resp. OSGi container installations, a whole list of bundles require access to one and the same data source.
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7 This not only is a configuration nightmare, it also produces an unnecessary large number of unnecessary large pools.
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9 The new OSGi bundle {{code language="none"}}org.clazzes.util.jdbc-provider{{/code}} allows to configure multiple datasources, which are exported as OSGi services implementing the interface {{code language="none"}}javax.sql.DataSource{{/code}}.
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11 = {{id name="Multi-DataSourcepoolingwithJDBC-Provider-ConfiguringJDBC-ProviderDataSources"/}}Configuring JDBC-Provider DataSources =
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13 This package uses the configuration PID org.clazzes.jdbc.provider and may be configured with keys using the following patterns:
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15 |=(((
16 (% class="tablesorter-header-inner" %)
17 (((
18 Key
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20 )))|=(((
21 (% class="tablesorter-header-inner" %)
22 (((
23 Description
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25 )))
26 |(((
27 {{code language="none"}}
28 datasource.<datasourcename>.url
29 {{/code}}
30 )))|(((
31 JDBC URL
32 )))
33 |(((
34 {{code language="none"}}
35 datasource.<datasourcename>.user
36 {{/code}}
37 )))|(((
38 JDBC User
39 )))
40 |(((
41 {{code language="none"}}
42 datasource.<datasourcename>.password
43 {{/code}}
44 )))|(((
45 JDBC Password
46 )))
47 |(((
48 {{code language="none"}}
49 datasource.<datasourcename>.validationQuery
50 {{/code}}
51 )))|(((
52 Validation query, executed to ensure the application receives a valid connection
53 )))
54
55 For more supported key patterns take a look at the JavaDoc of the [[org.clazzes.util.jdbc.provider.JdbcProvider>>url:http://svn.clazzes.org/svn/util/trunk/jdbc-provider/src/main/java/org/clazzes/util/jdbc/provider/JdbcProvider.java||shape="rect"]] class.
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57 Typical JDBC URLs and validation queries can be found in our [[doc:KH.Database Tips.JDBC Snippets.WebHome]].
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59 == {{id name="Multi-DataSourcepoolingwithJDBC-Provider-Configurationexample"/}}Configuration example ==
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61 (((
62 Sample configuration file {{code language="none"}}/etc/apache-karaf/org.clazzes.jdbc.provider.cfg{{/code}}:
63 )))
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65 {{code language="none"}}
66 datasource.JPTEST.url = jdbc:mysql://localhost/JPTEST
67 datasource.JPTEST.username = jptest
68 datasource.JPTEST.password = jptest321
69 datasource.JPTEST.validationQuery = SELECT 1
70 datasource.SPECTRUM.url = jdbc:oracle:thin:@10.1.2.3:1521:XE
71 datasource.SPECTRUM.maxActive = 8
72 datasource.SPECTRUM.username = FOO
73 datasource.SPECTRUM.password = bar
74 datasource.SPECTRUM.validationQuery = select SYSDATE from DUAL
75 {{/code}}
76
77 (% style="color: rgb(0,0,0);font-size: 24.0px;line-height: 1.25;" %)Developer Snippets
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79 == {{id name="Multi-DataSourcepoolingwithJDBC-Provider-pom.xmlSnippets"/}}pom.xml Snippets ==
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81 It's important for the maven-bundle-plugin to import the Package {{code language="none"}}javax.sql{{/code}}:
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83 {{code language="none"}}
84 ...
85 <build>
86 <plugins>
87 <plugin>
88 <groupId>org.apache.felix</groupId>
89 <artifactId>maven-bundle-plugin</artifactId>
90 <configuration>
91 <instructions>
92 ...
93 <Import-Package>*,javax.sql</Import-Package>
94 </instructions>
95 </configuration>
96 </plugin>
97 ...
98 </plugin>
99 ...
100 </build>
101 {{/code}}
102
103 But that's all you need!
104
105 == {{id name="Multi-DataSourcepoolingwithJDBC-Provider-BlueprintSnippets"/}}Blueprint Snippets ==
106
107 {{code language="none"}}
108 <bp:bean id="configProps" class="org.clazzes.util.osgi.ConfigPropertyAccessor" init-method="createDefaultConfig">
109 ...
110 <bp:property name="defaultValues">
111 <bp:map>
112 <bp:entry key="datasourceName" value="MYDATASOURCE"/>
113 ...
114 </bp:map>
115 </bp:property>
116 </bp:bean>
117 ...
118 <bp:bean id="datasourceName" factory-ref="configProps" factory-method="getProperty">
119 <bp:argument value="datasourceName" />
120 </bp:bean>
121 ...
122 <bp:bean id="datasourceMap" class="org.clazzes.util.osgi.ServiceMap" init-method="initialize">
123 <bp:property name="bundle" ref="blueprintBundle"/>
124 <bp:property name="keyProperty" value="datasource.name"/>
125 <bp:property name="serviceInterface" value="javax.sql.DataSource"/>
126 </bp:bean>
127 <bp:bean id="dataSource" factory-ref="datasourceMap" factory-method="getServiceProxy">
128 <bp:argument ref="datasourceName"/>
129 </bp:bean>
130 ...
131 <bp:bean id="myDao" ...>
132 <bp:property name="dataSource" ref="dataSource" />
133 </bp:bean>
134 {{/code}}
135
136 The blueprint xml can and should be kept free from any other JDBC stuff like URLs, driver magic and the like.
137
138 (% class="syntaxhighlighter nogutter java" %)
139 (((
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141 )))