Could not resolve placeholder in string value

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.

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"

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.

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.