I'm working on a webapp in Spring using Spring Tool Suite. If I build and deploy the application there using the IDE onto the provided Pivotal tc Server, it works just fine. However, if I do a manual "mvn clean package" build and attempt to deploy it to a standalone Tomcat server (using newest Tomcat 7), it throws the following exception:

```
2017-08-23 15:24:13 WARN  AnnotationConfigWebApplicationContext:551 - Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerAdapter' defined in org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter]: Factory method 'requestMappingHandlerAdapter' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mvcValidator' defined in org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration: Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: javax/el/ELManager
2017-08-23 15:24:13 ERROR DispatcherServlet:502 - Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerAdapter' defined in org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter]: Factory method 'requestMappingHandlerAdapter' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mvcValidator' defined in org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration: Invocation of init method failed; nested exception is java.lang.NoClassDefFoundError: javax/el/ELManager

```

Upon further inspection, it does complain few lines higher above about not loading jars:

```
sie 23, 2017 3:24:12 PM org.apache.catalina.startup.HostConfig deployWAR
INFO: Deploying web application archive D:\Apache-Tomcat-7.0\webapps\TestApp-0.0.1-SNAPSHOT.war
sie 23, 2017 3:24:12 PM org.apache.catalina.loader.WebappClassLoader validateJarFile
INFO: validateJarFile(D:\Apache-Tomcat-7.0\webapps\TestApp-0.0.1-SNAPSHOT\WEB-INF\lib\el-api-2.2.jar) - jar not loaded. See Servlet Spec 2.3, section 9.7.2. Offending class: javax/el/Expression.class
sie 23, 2017 3:24:12 PM org.apache.catalina.loader.WebappClassLoader validateJarFile
INFO: validateJarFile(D:\Apache-Tomcat-7.0\webapps\TestApp-0.0.1-SNAPSHOT\WEB-INF\lib\javax.servlet-api-3.1.0.jar) - jar not loaded. See Servlet Spec 2.3, section 9.7.2. Offending class: javax/servlet/Servlet.class
sie 23, 2017 3:24:12 PM org.apache.catalina.loader.WebappClassLoader validateJarFile
INFO: validateJarFile(D:\Apache-Tomcat-7.0\webapps\TestApp-0.0.1-SNAPSHOT\WEB-INF\lib\tomcat-el-api-8.0.21.jar) - jar not loaded. See Servlet Spec 2.3, section 9.7.2. Offending class: javax/el/Expression.class
2017-08-23 15:24:13 INFO  ContextLoader:304 - Root WebApplicationContext: initialization started

```

My pom.xml:

```
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.exmaple.mvc</groupId>
  <artifactId>TestApp</artifactId>
  <version>0.0.1-SNAPSHOT</version>
  <packaging>war</packaging>
  <dependencies>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-core</artifactId>
        <version>4.3.10.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>4.3.10.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-web</artifactId>
        <version>4.3.10.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-test</artifactId>
        <version>4.3.10.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-log4j12</artifactId>
        <version>1.6.6</version>
    </dependency>
    <dependency>
       <groupId>log4j</groupId>
       <artifactId>log4j</artifactId>
       <version>1.2.17</version>
       <exclusions>
        <exclusion>
            <artifactId>jms</artifactId>
            <groupId>javax.jms</groupId>
        </exclusion>
        <exclusion>
            <artifactId>jmxri</artifactId>
            <groupId>com.sun.jmx</groupId>
        </exclusion>
        <exclusion>
            <artifactId>jmxtools</artifactId>
            <groupId>com.sun.jdmk</groupId>
            </exclusion>
        </exclusions>
    </dependency>
        <dependency>
        <groupId>jstl</groupId>
        <artifactId>jstl</artifactId>
        <version>1.2</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.12</version>
        <scope>test</scope>
    </dependency>
    <!-- https://mvnrepository.com/artifact/org.mockito/mockito-all -->
    <dependency>
        <groupId>org.mockito</groupId>
        <artifactId>mockito-all</artifactId>
        <version>1.9.5</version>
        <scope>test</scope>
    </dependency>
    <!-- https://mvnrepository.com/artifact/commons-lang/commons-lang -->
    <dependency>
        <groupId>commons-lang</groupId>
        <artifactId>commons-lang</artifactId>
        <version>2.3</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-validator -->
    <dependency>
        <groupId>org.hibernate</groupId>
        <artifactId>hibernate-validator</artifactId>
        <version>6.0.1.Final</version>
    </dependency>

    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
    </dependency>
  </dependencies>

    <build>
        <plugins>
            <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.1</version>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
            </configuration>
        </plugin>
        </plugins>
    </build>

</project>

```

What's the reason for this behavior and how can I solve this?

**EDIT** More information:

Adding `<scope>provided</scope>` to `javax.servlet-api` seems to fix the warning about `javax.servlet-api` not being loaded at the start. Problem with `el-api` still remains.

I've checked the tomcat/lib directory and it already contains `el-api.jar` in it, which is likely why it tells me it's not going to load the one I list in pom.xml. The thing is, adding `<scope>provided</scope>` doesn't fix it either. Whatever I do, it still complains gives me the same `java.lang.NoClassDefFoundError: javax/el/ELManager` error. 

**SOLUTION**

In addition to the part in the edit above regarding `javax.servlet-api` the problem with `el-api` was that I was running a Tomcat 7 with provided `el-api` jar in version 2.2. The missing class was introduced in el-api 3.0. Running the same webapp in Tomcat 8 (with el-api 3.0 jar) works properly.