Spring之Condition（一）

直接上代码

　　

@Configuration
public class ConditionalAutoConfig {

    @Bean
    @Conditional(RandIntCondition.class)
    public RandDataComponent<Integer> randIntComponent() {
        return new RandDataComponent<>(() -> {
            Random random = new Random();
            return random.nextInt(1024);
        });
    }

    @Bean
    @Conditional(RandBooleanCondition.class)
    public RandDataComponent<Boolean> randBooleanComponent() {
        return new RandDataComponent<>(() -> {
            Random random = new Random();
            return random.nextBoolean();
        });
    }
}

public class RandBooleanCondition implements Condition {
    @Override
    public boolean matches(ConditionContext conditionContext, AnnotatedTypeMetadata annotatedTypeMetadata) {
        String type = conditionContext.getEnvironment().getProperty("conditional.rand.type");
        return "boolean".equalsIgnoreCase(type);
    }
}

public class RandIntCondition implements Condition {
    @Override
    public boolean matches(ConditionContext conditionContext, AnnotatedTypeMetadata annotatedTypeMetadata) {
        String type = conditionContext.getEnvironment().getProperty("conditional.rand.type");
        return "int".equalsIgnoreCase(type);
    }
}

public class RandDataComponent<T> {
    private Supplier<T> rand;

    public RandDataComponent(Supplier<T> rand) {
        this.rand = rand;
    }

    public T rand() {
        return rand.get();
    }
}

配置文件 application.yml

conditional:
      rand:
            type : int

@Autowired
    private Environment environment;
    @RequestMapping("/hello")
    public String index() {

//        return "Hello World MXZ" + port;
        String type = environment.getProperty("conditional.rand.type");
        return randDataComponent.rand() + " >>> " + type;
    }