为了从属性文件中选择值，我们可以有一个配置读取器类，比如ApplicationConfigReader.java 然后根据属性定义所有变量。参考下面的例子，

application.properties

myapp.nationality: INDIAN
myapp.gender: Male

下面是相应的阅读类。

@Component
@EnableConfigurationProperties
@ConfigurationProperties(prefix = "myapp") 
class AppConfigReader{
    private String nationality;
    private String gender

    //getter & setter
}

现在，我们可以在任何想要访问属性值的地方自动连接阅读器类。 如。

@Service
class ServiceImpl{
    @Autowired
    private AppConfigReader appConfigReader;

    //...
    //fetching values from config reader
    String nationality = appConfigReader.getNationality() ; 
    String gender = appConfigReader.getGender(); 
}

您可以使用@Value注释并访问spring bean中的属性

@Value("${userBucket.path}")
private String userBucketPath;

遵循以下步骤。 1:-创建你的配置类如下所示

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.beans.factory.annotation.Value;

@Configuration
public class YourConfiguration{

    // passing the key which you set in application.properties
    @Value("${userBucket.path}")
    private String userBucket;

   // getting the value from that key which you set in application.properties
    @Bean
    public String getUserBucketPath() {
        return userBucket;
    }
}

2:-当你有一个配置类时，然后从你需要的配置中注入变量。

@Component
public class YourService {

    @Autowired
    private String getUserBucketPath;

    // now you have a value in getUserBucketPath varibale automatically.
}

应用程序。Yml或application.properties

config.value1: 10
config.value2: 20
config.str: This is a simle str

MyConfig类

@Configuration
@ConfigurationProperties(prefix = "config")
public class MyConfig {
    int value1;
    int value2;
    String str;

    public int getValue1() {
        return value1;
    }

    // Add the rest of getters here...      
    // Values are already mapped in this class. You can access them via getters.
}

任何想要访问配置值的类

@Import(MyConfig.class)
class MyClass {
    private MyConfig myConfig;

    @Autowired
    public MyClass(MyConfig myConfig) {
        this.myConfig = myConfig;
        System.out.println( myConfig.getValue1() );
    }
}

另一种方法是将org.springframework.core. environment注入到bean中。

@Autowired
private Environment env;
....

public void method() {
    .....  
    String path = env.getProperty("userBucket.path");
    .....
}

你可以使用@ConfigurationProperties来访问application.properties中定义的值，这很简单

#datasource
app.datasource.first.jdbc-url=jdbc:mysql://x.x.x.x:3306/ovtools?useUnicode=true&useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC
app.datasource.first.username=
app.datasource.first.password=
app.datasource.first.driver-class-name=com.mysql.cj.jdbc.Driver
server.port=8686
spring.jpa.hibernate.ddl-auto=update
spring.jpa.generate-ddl=true
spring.jpa.show-sql=true
spring.jpa.database=mysql

@Slf4j
@Configuration
public class DataSourceConfig {
    @Bean(name = "tracenvDb")
    @Primary
    @ConfigurationProperties(prefix = "app.datasource.first")
    public DataSource mysqlDataSourceanomalie() {
        return DataSourceBuilder.create().build();
    }

    @Bean(name = "JdbcTemplateenv")
    public JdbcTemplate jdbcTemplateanomalie(@Qualifier("tracenvDb") DataSource datasourcetracenv) {
        return new JdbcTemplate(datasourcetracenv);
    }