java way to read the configuration file

方式一：
//创建Properties对象
Properties prop = new Properties();
//读取classPath中的properties文件
prop.load(ConsumerController.class.getClassLoader().getResourceAsStream("bean.properties"));
//根据键取出值
String className = prop.getProperty("test");//读取bean.properties里面，test的值

 

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Second way:

When using the tools, the property @Value ( "server.port) similar assignments, class of service plus @Component injection, access to content, just @Autowired service tool

Class, call the property

@Component
@Data
public class Student {
    @Value("${server.port}")
    private String port;
}

@Autowired
private Student student; 使用时直接注入，然后调用属性值

private static String port;
// If the property is static, you can use method injection
@Value("${server.port}")
public void setPort(Integer port) {
    Student.port= port;
}

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Three ways:

The introduction of dependence

<dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-configuration-processor</artifactId>
        <optional>true</optional>
    <version>2.2.5.RELEASE</version>
    </dependency>

@Component//不加无法注入
@Data//插件lombok帮助省略getset
@EnableConfigurationProperties(Student.class)
@ConfigurationProperties(prefix = "spring.activemq", ignoreUnknownFields = true)//加上注解提示有问题（提示没有经过EnableConfigurationProperties...spring的组件，你懂了，要加上EnableConfigurationProperties这个注解，才能成为spring组件）
public class Student {
    private String brokerUrl;
}调用方式不在描述，依赖注入直接调用