How to check two condition while using @ConditionalOnProperty or @ConditionalOnExpression

问题

I need to check that two conditions are satisfied on a YAML property file, while creating a bean. How do I do that, as the @ConditionalOnProperty annotation supports only one property?

回答1:

Use @ConditionalOnExpression annotation and SpEL expression as described here http://docs.spring.io/spring/docs/current/spring-framework-reference/html/expressions.html.

Example:

@Controller
@ConditionalOnExpression("${controller.enabled} and ${some.value} > 10")
public class WebController {

回答2:

Since from the beginning of @ConditionalOnProperty it was possible to check more than one property. The name / value attribute is an array.

@Configuration
@ConditionalOnProperty({ "property1", "property2" })
protected static class MultiplePropertiesRequiredConfiguration {

    @Bean
    public String foo() {
        return "foo";
    }

}

For simple boolean properties with an AND check you don't need a @ConditionalOnExpression.

回答3:

You might be interested in the AllNestedConditions abstract class that was introduced in Spring Boot 1.3.0. This allows you to create composite conditions where all conditions you define must apply before any @Bean are initialized by your @Configuration class.

public class ThisPropertyAndThatProperty extends AllNestedConditions {

    @ConditionalOnProperty("this.property")
    @Bean
    public ThisPropertyBean thisProperty() {
    }

    @ConditionalOnProperty("that.property")
    @Bean
    public ThatPropertyBean thatProperty() {
    }

}

Then you can annotate your @Configuration like this:

@Conditional({ThisPropertyAndThatProperty.class}
@Configuration

回答4:

Resolved the issue by using @ConditionalOnExpression for the two properties together.

@ConditionalOnExpression("'${com.property1}${com.property2}'=='value1value2'")

Wherein property value in configuration is as below.

Property 1 Name - com.property1 Value - value1

Property 2 Name - com.property2 Value - value2

来源：https://stackoverflow.com/questions/36016864/how-to-check-two-condition-while-using-conditionalonproperty-or-conditionalone

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spring-boot

netflix-eureka

spring-cloud-netflix