java。lang。IllegalArgumentException

　　Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder ＂fileServerUrl＂ in value ＂${fileServerUrl}＂
　　（解决方案在最下方）
　　org.springframework.beans.factory.BeanCreationException: Error creating bean with name ＂configProperties＂: Injection of autowired dependencies failed; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder ＂basePath＂ in value ＂${basePath}＂
　　at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:405)
　　at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1422)
　　at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:594)
　　at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517)
　　at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323)
　　at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:226)
　　at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321)
　　at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202)
　　at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:895)
　　at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:878)
　　at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550)
　　at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:401)
　　at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:292)
　　at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:103)
　　at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4716)
　　at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5177)
　　at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
　　at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:717)
　　at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:690)
　　at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:706)
　　at org.apache.catalina.startup.HostConfig.manageApp(HostConfig.java:1727)
　　at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
　　at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
　　at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
　　at java.lang.reflect.Method.invoke(Method.java:498)
　　at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:288)
　　at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
　　at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
　　at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:459)
　　at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:408)
　　at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
　　at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
　　at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
　　at java.lang.reflect.Method.invoke(Method.java:498)
　　at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:288)
　　at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
　　at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
　　at com.sun.jmx.remote.security.MBeanServerAccessController.invoke(MBeanServerAccessController.java:468)
　　at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1468)
　　at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:76)
　　at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1309)
　　at java.security.AccessController.doPrivileged(Native Method)
　　at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1408)
　　at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:829)
　　at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
　　at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
　　at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
　　at java.lang.reflect.Method.invoke(Method.java:498)
　　at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:357)
　　at sun.rmi.transport.Transport$1.run(Transport.java:200)
　　at sun.rmi.transport.Transport$1.run(Transport.java:197)
　　at java.security.AccessController.doPrivileged(Native Method)
　　at sun.rmi.transport.Transport.serviceCall(Transport.java:196)
　　at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568)
　　at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826)
　　at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:683)
　　at java.security.AccessController.doPrivileged(Native Method)
　　at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682)
　　at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
　　at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
　　at java.lang.Thread.run(Thread.java:748)
　　Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder ＂basePath＂ in value ＂${basePath}＂
　　at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:178)
　　at org.springframework.util.PropertyPlaceholderHelper.replacePlaceholders(PropertyPlaceholderHelper.java:124)
　　at org.springframework.core.env.AbstractPropertyResolver.doResolvePlaceholders(AbstractPropertyResolver.java:236)
　　at org.springframework.core.env.AbstractPropertyResolver.resolveRequiredPlaceholders(AbstractPropertyResolver.java:210)
　　at org.springframework.context.support.PropertySourcesPlaceholderConfigurer.lambda$processProperties$0(PropertySourcesPlaceholderConfigurer.java:175)
　　at org.springframework.beans.factory.support.AbstractBeanFactory.resolveEmbeddedValue(AbstractBeanFactory.java:912)
　　at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1247)
　　at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1226)
　　at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:640)
　　at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:130)
　　at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:399)
　　... 60 more
　　原因
　　在spring配置文件中使用了两次这个properties文件加载代码。
　　标签提供了一种外在化参数配置的方式，但该标签在spring配置文件中只能存在一份。
　　所以这就是报错了的原因，只能有一个标签。
　　解决
　　为每个标签添加ignore-unresolvable=＂true＂属性。
　　ignore-unresolvable：意思是是否忽略解析不到的属性，如果不忽略，找不到将抛出异常
　　正确代码