我使用Spring Boot示例从属性文件中读取以下内容。
sub.region.data={
AF: {'subRegionCd' : '34', 'subRegionName' : 'Southern Asia', 'subRegionDesc': '', 'status' : 'A'}
}
我用过下面的,但它不起作用
@Value("#{${sub.region.data}}")
private Map<String, SubRegion> subRegionsMap;
SubRegion.java
public class SubRegion {
private String subRegionCd;
private String subRegionName;
private String subRegionDesc;
private String subRegionStatus;
}
我得到低于错误
Caused by: org.springframework.beans.ConversionNotSupportedException: Failed to convert value of type 'java.util.Collections$UnmodifiableMap' to required type 'java.util.Map'; nested exception is java.lang.IllegalStateException: Cannot convert value of type 'java.util.Collections$UnmodifiableMap' to required type 'com.xxxxxx.model.SubRegion': no matching editors or conversion strategy found
at org.springframework.beans.TypeConverterSupport.convertIfNecessary(TypeConverterSupport.java:76) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1195) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1167) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:593) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
... 54 common frames omitted
Caused by: java.lang.IllegalStateException: Cannot convert value of type 'java.util.Collections$UnmodifiableMap' to required type 'com.xxxxxx.model.SubRegion': no matching editors or conversion strategy found
at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:262) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.TypeConverterDelegate.convertToTypedMap(TypeConverterDelegate.java:608) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:182) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
at org.springframework.beans.TypeConverterSupport.convertIfNecessary(TypeConverterSupport.java:73) ~[spring-beans-5.1.5.RELEASE.jar:5.1.5.RELEASE]
... 57 common frames omitted
看起来您在'subRegionDesc',
之后犯了一个错误,我认为您的意思是使用冒号,而不是逗号
对于spring-boot,我建议您使用ConfigurationProperties,而不是@Value
。
例如,在这种情况下,您必须:
-
将
@EnableConfigurationProperties(SubRegionConfig.class)
放到您的一个spring配置类中。 -
创建配置类:
@ConfigurationProperties(prefix = "sub.region") public static class SubRegionConfig { private Map<String, SubRegion> data; //getters and setters }
-
使用
.yml
而不是.properties
,就像这样:sub: region: data: AF: subRegionCd: '34' subRegionName: 'Southern Asia' subRegionDesc: '' subRegionStatus: 'A'
-
之后,您可以从
SubRegionConfing
中获得您想要的所有属性@Autowired private SubRegionConfig subRegionConfig;
ConfigurationsProperties
更复杂,但在大多数情况下更灵活,更适合使用。
#{}操作符将数据发送到spEL解析器,这意味着它将尝试根据Spring Docs中的spEL语法将数据转换为已知类型。
发生的情况是编译器无法将任何数据转换为SubRegion对象:
无法转换类型为"java.util.Collections$UnmodifiebleMap"的值到所需类型"com.xxxxxx.model.SubRegion":没有匹配的编辑器或找到的转换策略
一个简单的解决方法是嵌套两个Map对象,以便在检索值后填充SubRegion对象。
yourMap={'key1':{'nestedMapKey1:value', 'nestedMapKey2:value2'}}
在你的.properties文件和你的代码中:
sub.region.data={'AF':{'subRegionCd':'34', 'subRegionName':'Southern Asia', 'subRegionDesc':'', 'status':'A'}}
然后,在你的代码中:
@Value("#{${sub.region.data}}")
private Map<String, Map<String, String>> subRegionsMap;
// (...) handling the SubRegion
我的System.out.println(subRegionMap.get("AF"(输出:
{subRegionCd=34, subRegionName=Southern Asia, subRegionDesc=, status=A}