SpringBoot不替换Spring Tool Suite版本：3.8.4版本中的系统变量{user.home}

Question

我使用Spring Initializr生成了一个Spring Bootweb应用程序，使用macOS Sierra中的嵌入式Tomcat+Thymeleaf模板引擎。我想在Mac OS中使用系统变量User Home Folder Name

@Configuration
@Profile("dev")
@PropertySource("file:///{user.home}/.devopsbuddy/application-dev.properties")
public class DevelopmentConfig {

    @Bean
    public EmailService emailService() {
        return new MockEmailService();
    }

}

但我在启动应用程序时出现了这个错误

Caused by: java.io.FileNotFoundException: /{user.home}/.devopsbuddy/application-dev.properties (No such file or directory)
    at java.io.FileInputStream.open0(Native Method)
    at java.io.FileInputStream.open(FileInputStream.java:195)
    at java.io.FileInputStream.<init>(FileInputStream.java:138)
    at java.io.FileInputStream.<init>(FileInputStream.java:93)
    at sun.net.www.protocol.file.FileURLConnection.connect(FileURLConnection.java:90)
    at sun.net.www.protocol.file.FileURLConnection.getInputStream(FileURLConnection.java:188)
    at org.springframework.core.io.UrlResource.getInputStream(UrlResource.java:169)
    at org.springframework.core.io.support.EncodedResource.getInputStream(EncodedResource.java:154)
    at org.springframework.core.io.support.PropertiesLoaderUtils.fillProperties(PropertiesLoaderUtils.java:98)
    at org.springframework.core.io.support.PropertiesLoaderUtils.fillProperties(PropertiesLoaderUtils.java:72)
    at org.springframework.core.io.support.PropertiesLoaderUtils.loadProperties(PropertiesLoaderUtils.java:58)
    at org.springframework.core.io.support.ResourcePropertySource.<init>(ResourcePropertySource.java:65)
    at org.springframework.core.io.support.DefaultPropertySourceFactory.createPropertySource(DefaultPropertySourceFactory.java:36)
    at org.springframework.context.annotation.ConfigurationClassParser.processPropertySource(ConfigurationClassParser.java:440)
    at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:271)
    at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:245)
    at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:190)
    at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:292)
    at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:245)
    at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:198)
    at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:167)
    ... 13 common frames omitted

Answer 1

@PropertySource最初是作为Spring 3.1的一部分添加的，用于导入资源

在@PropertySource Java文档中指出,

@PropertySource资源位置中存在的任何${…}占位符都将根据已针对环境注册的属性源集进行解析。

@Configuration
@PropertySource(value = "classpath:application.properties")
public class ApplicationConfig {

    // more configuration ...
}

@Configuration
@PropertySource("application.properties")
public class ApplicationConfig {
}

@PropertySource("file:/path/to/application.properties")

或者您可以使用

@PropertySource("file:${CONF_DIR}/application.properties")

$ echo $CONF_DIR
/path/to/directory/with/app/config/files

在您的情况下，您必须使用`

@PropertySource（“文件：${user.home}/application.properties”）

 $ echo $user.home
 /home/yourusername

第一个新功能：

它处理丢失的文件。默认情况下，如果Spring没有找到已经声明的文件，它将抛出一个异常。

@PropertySource(value = "missing.properties", ignoreResourceNotFound = true)

如果不使用IgnoreResourceNotFound=true，它将给出以下错误。

java.lang.IllegalStateException: Failed to load ApplicationContext
[...]
Caused by: java.io.FileNotFoundException: class path resource [missing.properties] cannot be opened because it does not exist.

@PropertySources({
    @PropertySource("default.properties"),
    @PropertySource("overriding.properties")
})

把它放在一起

总而言之，属性源配置可以实现如下：

@Configuration
@PropertySources({
    @PropertySource("default.properties"),
    @PropertySource(value = "file:${CONF_DIR}/optional-override.properties", ignoreResourceNotFound = true)
}
public class ApplicationConfig {
}

在Java 8中

@Manufactures({
@Manufacturer(name =”BMW”),
@Manufacturer(name = “Range Rover”)

})
public class Car{
//code goes in here
}

@Manufacturer(name = “BMW”)
@Manufacturer(name= “Range Rover”)
public class Car{
//code goes in here
}

所有的功劳都归于马蒂亚斯·塞弗森

1. Spring@PropertySource
2. Java 8重复注释5分钟解释