将Spring@Value注释评估为原始布尔值

Question

我有一个 Spring @Configuration 注释类 MappingsClientConfig，其布尔字段为：

 @Value("${mappings.enabled:true}")
 private boolean mappingsEnabled;

这个类被导入到另一个Spring注释类中，如下所示：

@Configuration
@Import(MappingsClientConfig.class)
public class LookupManagerConfig {

在测试用例中通过Spring上下文实例化类时，容器无法将字符串解析为布尔字段＜code＞mappingsEnabled＜/code＞，我得到：

Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private boolean com.barcap.tcw.mappings.economic.client.config.EconomicMappingsClientConfig.economicMappingsEnabled; nested exception is org.springframework.beans.TypeMismatchException: Failed to convert value of type 'java.lang.String' to required type 'boolean'; nested exception is java.lang.IllegalArgumentException: Invalid boolean value [${mappings.enabled:true}]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:502)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:84)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:282)
    ... 138 more
Caused by: org.springframework.beans.TypeMismatchException: Failed to convert value of type 'java.lang.String' to required type 'boolean'; nested exception is java.lang.IllegalArgumentException: Invalid boolean value [${mappings.enabled:true}]
    at org.springframework.beans.SimpleTypeConverter.convertIfNecessary(SimpleTypeConverter.java:61)
    at org.springframework.beans.SimpleTypeConverter.convertIfNecessary(SimpleTypeConverter.java:43)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:718)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:703)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:474)
    ... 140 more
Caused by: java.lang.IllegalArgumentException: Invalid boolean value [${mappings.enabled:true}]
    at org.springframework.beans.propertyeditors.CustomBooleanEditor.setAsText(CustomBooleanEditor.java:124)
    at org.springframework.beans.TypeConverterDelegate.doConvertTextValue(TypeConverterDelegate.java:416)
    at org.springframework.beans.TypeConverterDelegate.doConvertValue(TypeConverterDelegate.java:388)
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:157)
    at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:93)
    at org.springframework.beans.SimpleTypeConverter.convertIfNecessary(SimpleTypeConverter.java:49)
    ... 144 more

关于我错过了什么的任何线索？

Answer 1

这就是我们项目中解决这个问题的方式，因为其他答案对我们不起作用。我们也在使用春批。

主要作业配置：

@Configuration
@EnableBatchProcessing
@PropertySource("classpath:application.properties")
public class MainJobConfiguration {
    @Autowired
    PipelineConfig config;

    @Bean
    public PipelineConfig pipelineConfig(){
        return new PipelineConfig();
    }

    // To resolve ${} in @Value
    @Bean
    public static PropertySourcesPlaceholderConfigurer propertyConfigInDev() {
        return new PropertySourcesPlaceholderConfigurer();
    }

    // job stuff ...
}

属性配置加载程序:

public class PipelineConfig {
    @Value("${option}")
    private boolean option;
}

请注意@Value是如何在PipelineConfig中的，但加载选项的实际属性是在作业类中指定的。

Answer 2

看起来您缺少 PropertyPlaceholderConfigurer。您需要将其注册为 Bean 工厂后处理器。从理论上讲，这可以像这样完成：

public class PostProcessorConfig {

    @Bean
    public BeanFactoryPostProcessor getPP() {
       PropertyPlaceholderConfigurer configurer = new PropertyPlaceholderConfigurer();
       configurer.setLocations(new Resource[]{new ClassPathResource("/my.properties")});
       return configurer;
    }
}

然而，在基于java的配置中，似乎存在导致其他问题的bug。有关解决方法，请参阅票据。

Answer 3

这是一个旧线程，但如果您仍然想使用 Spring 注释注入非字符串值@Value请执行以下操作：

@Value("#{new Boolean('${item.priceFactor}')}")
private Boolean itemFactorBoolean;

@Value("#{new Integer('${item.priceFactor}')}")
private Integer itemFactorInteger;

在带有Java 8的Spring boot 1.5.9上为我工作。