无法解析字符串值中的占位符 [英] Could not resolve placeholder in string value
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问题描述
我正在尝试使用 .properties 文件中的属性，但它似乎不起作用。
I am trying to use properties from a .properties file, but it doesn't seem to work.
这是我的代码：
@Service("ServiceFTP")
@Transactional
public class ServiceFTPImpl implements ServiceFTP {
@Value("${project.ftp.adresse}")
private String adresse;
@Value("${project.ftp.login}")
private String compte;
@Value("${project.ftp.password}")
private String motDePasse;
@Value("${project.ftp.root}")
private String ROOT;
[...]
}
此类使用 @Value 注释来获取属性。
它也被声明为Spring服务并链接到我的 infraContext.xml 文件：
This class uses @Value annotations to get the properties.
It is also declared as a Spring Service and is linked to my infraContext.xml file :
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.2.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.2.xsd">
<context:property-placeholder location="classpath:context-core.properties"/>
[...]
</beans>
使用 context：property-placeholder ，I将此文件链接到我的 context-core.properties 文件：
Using context:property-placeholder, I link this file to my context-core.properties file :
project.ftp.adresse = localhost
project.ftp.login = anonymous
project.ftp.password =
project.ftp.root = /anonymous/
这确实有意义，对吗？
但是当我尝试启动我的项目时， Tomcat抛出此异常：
But when I try to launch my project, Tomcat throw this exception :
ERROR [context.ContextLoader.initWebApplicationContext()] Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'ServiceFTP': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private java.lang.String project.sins.service.impl.ServiceFTPImpl.adresse; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'project.ftp.adresse' in string value "${project.ftp.adresse}"
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:287)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1106)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:294)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:607)
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:925)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:472)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:388)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:293)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4887)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5381)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:633)
at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:657)
at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1636)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:722)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private java.lang.String project.sins.service.impl.ServiceFTPImpl.adresse; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'project.ftp.adresse' in string value "${project.ftp.adresse}"
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:513)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:92)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:284)
... 27 more
Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder 'project.ftp.adresse' in string value "${project.ftp.adresse}"
at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:173)
at org.springframework.util.PropertyPlaceholderHelper.replacePlaceholders(PropertyPlaceholderHelper.java:125)
at org.springframework.core.env.AbstractPropertyResolver.doResolvePlaceholders(AbstractPropertyResolver.java:151)
at org.springframework.core.env.AbstractPropertyResolver.resolveRequiredPlaceholders(AbstractPropertyResolver.java:142)
at org.springframework.context.support.PropertySourcesPlaceholderConfigurer$2.resolveStringValue(PropertySourcesPlaceholderConfigurer.java:169)
at org.springframework.beans.factory.support.AbstractBeanFactory.resolveEmbeddedValue(AbstractBeanFactory.java:748)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:740)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:730)
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:485)
... 29 more
或者，简而言之： java.lang.IllegalArgumentException：无法解析占位符' project.ftp.adresse'字符串值$ {project.ftp.adresse}
编辑：
这是我的web.xml：
Here is my web.xml :
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
id="sins" version="2.5">
<display-name>Project</display-name>
<listener>
<listener-class>org.springframework.web.util.Log4jConfigListener</listener-class>
</listener>
<context-param>
<param-name>log4jExposeWebAppRoot</param-name>
<param-value>false</param-value>
</context-param>
<filter>
<filter-name>ExpiresFilter</filter-name>
<filter-class>org.apache.catalina.filters.ExpiresFilter</filter-class>
<init-param>
<param-name>ExpiresByType text/html</param-name>
<param-value>now plus 0 seconds</param-value>
</init-param>
<init-param>
<param-name>ExpiresByType application/json</param-name>
<param-value>now plus 0 seconds</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>ExpiresFilter</filter-name>
<url-pattern>/*</url-pattern>
<dispatcher>REQUEST</dispatcher>
</filter-mapping>
<filter>
<filter-name>EncodingFilter</filter-name>
<filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
<init-param>
<param-name>encoding</param-name>
<param-value>UTF-8</param-value>
</init-param>
<init-param>
<param-name>forceEncoding</param-name>
<param-value>true</param-value>
</init-param>
</filter>
<filter-mapping>
<filter-name>EncodingFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>springSecurityFilterChain</filter-name>
<filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
</filter>
<filter-mapping>
<filter-name>springSecurityFilterChain</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
<filter-class>
org.springframework.orm.jpa.support.OpenEntityManagerInViewFilter
</filter-class>
</filter>
<filter-mapping>
<filter-name>Spring OpenEntityManagerInViewFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<listener>
<listener-class>org.apache.struts2.tiles.StrutsTilesListener</listener-class>
</listener>
<context-param>
<param-name>
org.apache.tiles.impl.BasicTilesContainer.DEFINITIONS_CONFIG
</param-name>
<param-value>
/WEB-INF/tiles/user.xml
</param-value>
</context-param>
<resource-ref>
<res-ref-name>jdbc/si_nsg</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
<session-config>
<session-timeout>60</session-timeout>
</session-config>
</web-app>
我的infraContext.xml是在另一个名为applicationContext.xml的.xml文件中导入的：
My infraContext.xml is imported in another .xml file named applicationContext.xml :
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:jee="http://www.springframework.org/schema/jee"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee-3.1.xsd">
<bean class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer">
<property name="environment">
<bean class="org.springframework.web.context.support.StandardServletEnvironment"/>
</property>
</bean>
<import resource="classpath:securityContext.xml"/>
[...]
<import resource="classpath:project/sins/persistenceContext.xml"/>
<import resource="classpath:project/sins/infraContext.xml"/>
</beans>
我显然遗漏了一些东西，但我无法弄清楚是什么。
I am obviously missing something, but I can't figure out what.
如果您需要更多详细信息，请告诉我，因为这是我的第一个问题，我会尽快回答:)。
Please let me know if you need more details, as it is my first question here, I'll try to answer as soon as I can :).
推荐答案
在您的配置中，您有2 PropertySourcesPlaceholderConfigurer 个实例。
In your configuration you have 2 PropertySourcesPlaceholderConfigurer instances.
applicationContext.xml
applicationContext.xml
<bean class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer">
<property name="environment">
<bean class="org.springframework.web.context.support.StandardServletEnvironment"/>
</property>
</bean>
infraContext.xml
infraContext.xml
<context:property-placeholder location="classpath:context-core.properties"/>
默认情况下， PlaceholderConfigurer 将失败-fast，所以如果占位符无法解析，它将抛出异常。 applicationContext.xml 文件中的实例没有属性，因此在所有占位符上都会失败。
By default a PlaceholderConfigurer is going to fail-fast, so if a placeholder cannot be resolved it will throw an exception. The instance from the applicationContext.xml file has no properties and as such will fail on all placeholders.
解决方案：从 applicationContext.xml 中删除它，因为它不会添加任何只会破坏它的东西。
Solution: Remove the one from applicationContext.xml as it doesn't add anything it only breaks things.
这篇关于无法解析字符串值中的占位符的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
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