Expression Language in Guice Named properties
guice-properties-el supports Expression Language 2.1 syntax (variables, method calls, conditions, etc.).
By default guice-properties-el provides env and properties variables.
Here's a simple properties test.properties file:
# env == System.getenv()
test.env.home=${env['HOME']}
# properties == System.getProperties()
test.properties.javaVersion=${properties['java.version']}
# EL 2.1 features like method calls and condition:
test.eval=${env.containsKey('TRAVIS') ? 'on travis' : 'locally'}
The above properties are mapped using @Named and @Inject annotations:
public class TestModel {
@Inject
@Named("test.env.home")
private String testEnvHome;
@Inject
@Named("test.properties.javaVersion")
private String testPropertiesJavaVersion;
@Inject
@Named("test.eval")
private String testEval;
}
Finally, create the injector and get the instance:
Injector injector = Guice.createInjector(new PropertiesElResolverModule("/test.properties"));
TestModel testModel = injector.getInstance(TestModel.class);
See src/test/java for lots of unit tests and examples.
Use the following Maven dependency:
<dependency>
<groupId>com.github.lukaszbudnik.guice-properties-el</groupId>
<artifactId>guice-properties-el</artifactId>
<version>{version}</version>
</dependency>Copyright 2015 Łukasz Budnik
Licensed 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.