我在Spring Boot中使用了@Value批注,但是它似乎并没有像我期望的那样完全起作用。

在我的@Configuration文件中:

@Value("${installationDirectory}")
private File m_installationDirectory;

在我的application.properties中:
installationDirectory=${user.dir}/install

启动:
public static void main( String[] args ) throws IOException
{
    logger.info( "Starting application" );
    logger.info( "Java version: {}", System.getProperty( "java.version" ) );
    logger.info( "Java home   : {}", System.getProperty( "java.home" ) );
    logger.info( "Operation System: {} {} ({})", System.getProperty( "os.name" ), System.getProperty( "os.version" ), System.getProperty( "os.arch" ) );
    logger.info( "Working dir : {}", System.getProperty( "user.dir" ) );

    SpringApplication springApplication = new SpringApplication( Main.class );
    springApplication.setShowBanner( false );
    ConfigurableApplicationContext context = springApplication.run( args );
}

启动时输出:
2014-05-14 09:36:05 INFO [main] Main - Starting application
2014-05-14 09:36:05 INFO [main] Main - Java version: 1.7.0_55
2014-05-14 09:36:05 INFO [main] Main - Java home   : /Library/Java/JavaVirtualMachines/jdk1.7.0_55.jdk/Contents/Home/jre
2014-05-14 09:36:05 INFO [main] Main - Operation System: Mac OS X 10.9.2 (x86_64)
2014-05-14 09:36:05 INFO [main] Main - Working dir : /Users/wdb/Work/netty-test
2014-05-14 09:36:05 INFO [main] Main - Starting Main on bruk-00007-l.zone2.flir.net with PID 98296 (/Users/wdb/Work/netty-test/flux-server/flux-server-application/target/classes started by wdb)
2014-05-14 09:36:05 DEBUG [main] Main - Running with Spring Boot v1.0.1.RELEASE, Spring v4.0.3.RELEASE
2014-05-14 09:36:08 INFO [main] LoggingToFileMessageRepositoryDecorator - Storing messages in /Users/wdb/Library/Caches/IntelliJIdea13/compile-server/install/messages
2014-05-14 09:36:08 INFO [main] OnDiskSingleJvmImageRepository - Storing images in folder /Users/wdb/Library/Caches/IntelliJIdea13/compile-server/install/images
2014-05-14 09:36:08 INFO [main] TrafficDataIntegratorsManagerImpl - Created 3 integrators for 1 sources in 1 ms
2014-05-14 09:36:09 INFO [main] Main - Started Main in 3.928 seconds (JVM running for 4.428)

请注意,如果我仅打印它,则系统属性user.dir指向/Users/wdb/Work/netty-test。但是,在将installationDirectory值注入到Spring bean中的情况下,路径似乎是/Users/wdb/Library/Caches/IntelliJIdea13/compile-server/install/而不是预期的/Users/wdb/Work/netty-test/install
请注意,我是从IntelliJ 13.1.2运行的,在运行配置中将“工作目录”设置为/Users/wdb/Work/netty-test

最佳答案

我发现了问题。我正在与Maven合作。 spring-boot-starter-parent默认为application.properties启用资源过滤:

<!-- Turn on filtering by default for application properties -->
<resources>
    <resource>
        <directory>src/main/resources</directory>
        <filtering>true</filtering>
        <includes>
            <include>**/application.yml</include>
            <include>**/application.properties</include>
        </includes>
    </resource>
    <resource>
        <directory>src/main/resources</directory>
        <excludes>
            <exclude>**/application.yml</exclude>
            <exclude>**/application.properties</exclude>
        </excludes>
    </resource>
</resources>

看来${user.dir}也可以替代Maven。如果我在application.properties中查看target/classes,的确被替换了。

要解决此问题,我需要执行以下操作:

首先告诉Maven您想要escape filtering:
<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-resources-plugin</artifactId>
  <version>2.6</version>
  <configuration>
    <escapeString>\</escapeString>
  </configuration>
</plugin>

然后将application.properties文件更改为:
installationDirectory=\${user.dir}/install

之后,一切正常。

07-24 19:25