无法解析字符串值中的占位符

我试图使用来自 .properties文件的属性，但它似乎不起作用。

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;


[...]


}

这个类使用 @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:

<?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，我将这个文件链接到我的 context-core.properties文件:

project.ftp.adresse = localhost
project.ftp.login = anonymous
project.ftp.password =
project.ftp.root = /anonymous/

这说得通吧？

但是当我尝试启动我的项目时，Tomcat 抛出了这个异常:

    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: Could not resolve placeholder 'project.ftp.adresse' in string value "${project.ftp.adresse}"

编辑:

下面是我的 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>

Xml 导入到另一个名为 applicationContext.xml 的. xml 文件中:

<?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>

我显然遗漏了什么，但我不知道是什么。

如果你需要更多的细节，请告诉我，因为这是我在这里的第一个问题，我会尽快回答:)。

518026 次浏览
小开
最佳答案

In your configuration you have 2 PropertySourcesPlaceholderConfigurer instances.

applicationContext.xml

<bean class="org.springframework.context.support.PropertySourcesPlaceholderConfigurer">
<property name="environment">
<bean class="org.springframework.web.context.support.StandardServletEnvironment"/>
</property>
</bean>

infraContext.xml

<context:property-placeholder location="classpath:context-core.properties"/>

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.

Solution: Remove the one from applicationContext.xml as it doesn't add anything it only breaks things.

小开

I had the same problem, resolved it by adding

<filtering>true</filtering>

in pom.xml :

before (didn't work):

<build>
<resources>
<resource>
<directory>src/main/resources</directory>
</resource>
</resources>
</build>

after(it worked):

<build>
<resources>
<resource>
<directory>src/main/resources</directory>
<filtering>true</filtering>
</resource>
</resources>
</build>

After that you just run mvn clean install and deploy application.

小开

This Issue occurs if the application is unable to access the some_file_name.properties file.Make sure that the properties file is placed under resources folder in spring.

Trouble shooting Steps

1: Add the properties file under the resource folder.

2: If you don't have a resource folder. Create one by navigating new by Right click on the project new > Source Folder, name it as resource and place your properties file under it.

For annotation based Implementation

Add @PropertySource(ignoreResourceNotFound = true, value = "classpath:some_file_name.properties")//Add it before using the place holder

Example:

Assignment1Controller.Java

@PropertySource(ignoreResourceNotFound = true, value = "classpath:assignment1.properties")
@RestController
public class Assignment1Controller {


//  @Autowired
//  Assignment1Services assignment1Services;
@Value("${app.title}")
private String appTitle;
@RequestMapping(value = "/hello")
public String getValues() {


return appTitle;


}


}

assignment1.properties

app.title=Learning Spring
小开

In my case, I was careless while merging the application.yml file, and I've unnecessary indented my properties to the right.

I've indented it like this:

spring:
application:
name: applicationName
............................
myProperties:
property1: property1value

While the code expected it to be like this:

spring:
application:
name: applicationName
.............................
myProperties:
property1: property1value
小开

My solution was to add a space between the $ and the {.

For example:

@Value("${project.ftp.adresse}")

becomes

@Value("$ {project.ftp.adresse}")
小开

With Spring Boot :

In the pom.xml

<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<addResources>true</addResources>
</configuration>
</plugin>
</plugins>
</build>

Example in class Java

@Configuration
@Slf4j
public class MyAppConfig {
@Value("${foo}")
private String foo;
@Value("${bar}")
private String bar;
@Bean("foo")
public String foo() {
log.info("foo={}", foo);
return foo;
}
@Bean("bar")
public String bar() {
log.info("bar={}", bar);
return bar;
}
[ ... ]

In the properties files :

src/main/resources/application.properties

foo=all-env-foo

src/main/resources/application-rec.properties

bar=rec-bar

src/main/resources/application-prod.properties

bar=prod-bar

In the VM arguments of Application.java

-Dspring.profiles.active=[rec|prod]

Don't forget to run mvn command after modifying the properties !

mvn clean package -Dmaven.test.skip=true

In the log file for -Dspring.profiles.active=rec :

The following profiles are active: rec
foo=all-env-foo
bar=rec-bar

In the log file for -Dspring.profiles.active=prod :

The following profiles are active: prod
foo=all-env-foo
bar=prod-bar

In the log file for -Dspring.profiles.active=local :

Could not resolve placeholder 'bar' in value "${bar}"

Oups, I forget to create application-local.properties.

小开

You can also try default values. spring-value-annotation

Default values can be provided for properties that might not be defined. In this example the value “some default” will be injected:

@Value("${unknown.param:some default}")
private String someDefault;

If the same property is defined as a system property and in the properties file, then the system property would be applied.

小开

I got same error in my Micro-service, whenever you declare @Value annotation in program i.e @Value("${project.api.key}")

make sure that your application.properties file with same values should not be blank project.api.key= add some values

MostIMP :otherwise it will throw error "Error creating bean with name 'ServiceFTP': Injection of autowired dependencies"

小开

I got the same error in my microservice project.The property itself missed in my yml file.So I added property name and value that resolves my problem

小开

This error appears because the spring project doesn't read the file properties (bootstrap.yml or application.yml). In order to resolve this, you must add dependency in your pom.xml

   <dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-context</artifactId>
</dependency>
小开

I´m frequently running into this issue on some custom properties that could not be found using IntelliJ IDEA - likely after changing branches.

What helpes in my case is

File -> Invalidate Caches / Restart

I had the assumption that it is more likely a Gradle caching issue than an IDE issue, but ./gradle clean did not help

小开

In my case I had the same issue on running from eclipse. Just did the following to resolve it: Right Click the Project --> Mavan --> Update Project.

And it worked!

小开

I had a similar issue in the spring boot application.

When you add a property configuration to the application.properties file in main application SCR directory, make sure you do the same for application.properties file under the test directory.

小开

Adding same properties into application.properties would be helpful.

小开

I just added the configuration of the property in my application.xml file for my test folder, just the same way it is in my SRC folder and it solved my problem.

小开

I applied the same as Ben G and it worked for me. Try adding a space between $ and {

小开

Delete <packaging>pom</packaging> line in your pom.xml.


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