我的Spring XML中有两个PropertyPlaceHolderConfigurer。第一个从文件获取应用程序属性。第二个从数据库获取用户属性,如下所示:
<myConfiguration>
<bean id="databaseProperties"
class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
<property name="systemPropertiesModeName" value="SYSTEM_PROPERTIES_MODE_OVERRIDE" />
<property name="properties">
<bean class="org.apache.commons.configuration.ConfigurationConverter"
factory-method="getProperties">
<constructor-arg>
<ref bean="propertiesSource" />
</constructor-arg>
</bean>
</property>
</bean>
<bean id="propertiesSource" class="org.apache.commons.configuration.DatabaseConfiguration">
<constructor-arg type="javax.sql.DataSource" ref="tomcatDataSource" />
<constructor-arg value="application_properties" />
<constructor-arg value="PROPERTY_KEY" />
<constructor-arg value="PROPERTY_VALUE" />
</bean>
<bean id="propertiesService" class="com.xxx.PropertiesServiceImpl">
<property name="propertiesSource" ref="propertiesSource"></property>
</bean>
<myConfiguration>
它可以正常工作,我可以访问注入“ propertiesService”的这些属性,例如:
@Autowired
private PropertiesService propertiesService;
这是:
public class PropertiesServiceImpl implements PropertiesService {
@Autowired
private DatabaseConfiguration propertiesSource;
private Properties properties;
@Override
public String getProperty(String key) {
if (properties == null) {
properties = ConfigurationConverter.getProperties(propertiesSource);
}
return properties.getProperty(key);
}
@Override
public Properties getProperties() {
if (properties == null) {
properties = ConfigurationConverter.getProperties(propertiesSource);
}
return properties;
}
问题是我喜欢使用@Value注释,但是它不起作用。
我试过了:
private @Value("#{propertiesService.helloWorld}") String helloWorld;
并且,当然,该属性存在并且可以通过“ propertiesService”访问,但它会导致下一个错误:
Caused by: org.springframework.expression.spel.SpelEvaluationException: EL1008E:(pos 18): Property or field 'helloWorld' cannot be found on object of type 'com.infraportal.model.properties.PropertiesServiceImpl' - maybe not public?
at org.springframework.expression.spel.ast.PropertyOrFieldReference.readProperty(PropertyOrFieldReference.java:224)
at org.springframework.expression.spel.ast.PropertyOrFieldReference.getValueInternal(PropertyOrFieldReference.java:94)
at org.springframework.expression.spel.ast.PropertyOrFieldReference.access$000(PropertyOrFieldReference.java:46)
at org.springframework.expression.spel.ast.PropertyOrFieldReference$AccessorLValue.getValue(PropertyOrFieldReference.java:374)
at org.springframework.expression.spel.ast.CompoundExpression.getValueInternal(CompoundExpression.java:88)
at org.springframework.expression.spel.ast.SpelNodeImpl.getValue(SpelNodeImpl.java:120)
at org.springframework.expression.spel.standard.SpelExpression.getValue(SpelExpression.java:242)
at org.springframework.context.expression.StandardBeanExpressionResolver.evaluate(StandardBeanExpressionResolver.java:161)
这让我认为Spring正在寻找一种“ getHelloWorld()”方法,而不是使用“ getProperty(String key)”
有什么建议吗?
最佳答案
您需要在EL中引用的bean上明确指定要调用的方法,并提供如下的参数值
@Value("#{propertiesService.getProperty('helloWorld')}")
private String helloWorld;