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This article mainly introduces "what are the ways in which Spring Boot reads configuration files". In daily operation, I believe that many people have doubts about the way Spring Boot reads configuration files. The editor consulted all kinds of materials and sorted out simple and easy-to-use operation methods. I hope it will be helpful to answer the doubts about "what is the way Spring Boot reads configuration files?" Next, please follow the editor to study!

Generally speaking, there are three ways for Spring Boot to get files, which are @ Value annotation, @ ConfigurationProperties annotation and Environment interface. These three annotations can be used with @ PropertySource, which is mainly used to specify specific configuration files.

@ PropertySource resolution

@ Target (ElementType.TYPE)

@ Retention (RetentionPolicy.RUNTIME)

@ Documented

@ Repeatable (PropertySources.class)

Public @ interface PropertySource {

String name () default ""

String [] value ()

Boolean ignoreResourceNotFound () default false

String encoding () default ""

Class createPropertySource (String name, EncodedResource resource) throws IOException {

String sourceName = name! = null? Name: resource.getResource () .getFilename ()

If (! resource.getResource (). Exists ()) {

Return new PropertiesPropertySource (sourceName, new Properties ())

} else if (sourceName.endsWith (".yml") | | sourceName.endsWith (".yaml")) {

Properties propertiesFromYaml = loadYml (resource)

Return new PropertiesPropertySource (sourceName, propertiesFromYaml)

} else {

Return super.createPropertySource (name, resource)

}

}

Private Properties loadYml (EncodedResource resource) throws IOException {

YamlPropertiesFactoryBean factory = new YamlPropertiesFactoryBean ()

Factory.setResources (resource.getResource ())

Factory.afterPropertiesSet ()

Return factory.getObject ()

}

}

@ PropertySource (value = {"classpath:config.properties"}, encoding= "gbk", factory = YmlConfigFactory.class)

Second, Environment reads files

Configuration file We continue to use the above two to define a class to read the configuration file

@ Configuration

@ PropertySource (value = {"classpath:config.properties"}, encoding= "gbk")

Public class GetProperties {

@ Autowired

Environment environment

Public String getEnvConfig () {

String name = environment.getProperty ("zhbin.config.web-configs.name")

String age = environment.getProperty ("zhbin.config.web-configs.age")

Return name+ "-" + age

}

}

@ ConfigurationProperties reads the configuration file

@ ConfigurationProperties can map the configuration file directly to an entity class, and then we can directly manipulate the entity class to get the configuration file-related data.

Create a new yml file, and of course the properties file is fine.

Zhbin:

Config:

Web-configs:

Name: Java Journey

Age: 20

Create a new entity class to map the configuration

@ Component

@ ConfigurationProperties (prefix = "zhbin.config")

@ Data

Public class StudentYml {

/ / webConfigs must correspond to the configuration file and be written as hump naming method

Private WebConfigs webConfigs = new WebConfigs ()

@ Data

Public static class WebConfigs {

Private String name

Private String age

}

}

Prefix = "zhbin.config" is used to specify the profile prefix

If you need to get the list collection, you can make the following modifications.

Zhbin:

Config:

Web-configs:

-name: Java Journey

Age: 20

-name: Java Journey 2

Age: 202

@ Component

@ ConfigurationProperties (prefix = "zhbin.config")

@ Data

Public class StudentYml {

Private List webConfigs = new ArrayList ()

@ Data

Public static class WebConfigs {

Private String name

Private String age

}

}

Experience and pit

Properties files use iso8859-1 by default and cannot be modified

The loading order of the yml file is higher than that of properties, but it will be read and loaded when the configuration information is read

The @ PropertySource annotation loads only properties files by default

@ PropertySource annotations can be used in conjunction with either way

@ Value is recommended for simple values and @ ConfigurationProperties for complex objects.

At this point, the study on "what is the way Spring Boot reads configuration files" is over. I hope to be able to solve your doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!

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