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Setting up applicationContext.xml for a simple Spring app in Intellij Ultimate

I'm a complete newcomer to Spring and I'm trying to set up a simple Spring application which I'm following through an online tutorial. The tutor is using Eclipse however and IntelliJ is complaining
Cannot find the declaration of element 'beans'.
....from within applicationContext.xml
My only Spring POM dependency:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>5.1.9.RELEASE</version>
</dependency>
My applicationContext.xml
Do I have to setup this up from the 'Facets' context menu in Project Structure?? If so, how?
I have all the standard Spring plugins that come bundled in a typical Ultimate installation:
My project structure:

You have to use the following dependency also for Spring Beans apart from Spring Core.
<!-- https://mvnrepository.com/artifact/org.springframework/spring-beans -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>5.1.9.RELEASE</version>
</dependency>

How to determine the <parent> dependency for a set of springframework dependencies

I like to know if below is possible and how.
I was following a tutorial for spring boot and it was mentioned there we can have a parent dependency.
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.6.RELEASE</version>
</parent>
And then define the dependencies without the version number.
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
This will add the dependencies version 1.5.6.RELEASE of spring-boot-starter and spring-boot-starter-web in to the projects dependencies.
Just like that I want to find what is the <parent> code snippet for the following dependencies I need to add in to a new project.
Dependencies in <groupId>org.springframework</groupId>. I need to use the version 4.3.9.RELEASE.
spring-context
spring-jdbc
spring-test
Thanks!

If you are using Spring Boot then these three dependencies will be provided for you by the following starters:
spring-test will be provided by spring-boot-starter-test
spring-context will be provided by spring-boot-starter-data-jpa
spring-jdbc will be provided by spring-boot-starter-jdbc
So, with the following parent:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.6.RELEASE</version>
</parent>
... if you add these dependencies:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
... then you will get
spring-context
spring-jdbc
spring-test
However, Spring Boot 1.5.6.RELEASE depends on v4.3.10.RELEASE of those core Spring libraries not 4.3.9.RELEASE as suggested in your question. Typically, you would accept Spring's curation of dependencies so if Sping provides 4.3.10.RELEASE then either (a) you should use that version or (b) downgrade Spring Boot toa version which provides 4.3.9.RELEASE.
Read on for details on how to identify the correct starter for a given curated library ...
The spring-boot-starter-parent is a special starter that provides useful Maven defaults and a dependency-management section which defines numerous dependencies which you might want to use in your POM. These dependencies are often referred to as "curated" or "blessed" and since they are defined in a dependency-management section somewhere in the maven hierarchy you can refer to them in your POM without a version tag (i.e. they inherit the version from the dependency-management section entry.)
You can see the spring-boot-starter-parent POM here and peeking inside you can see that it references the spring-boot-dependencies POM here.
Looking at your question you mentioned that you can declare a dependency like so ...
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
... this is because the spring-boot-dependencies POM declares the following:
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>${revision}</version>
</dependency>
So, the parent and the starters are just a means of wrapping up dependency declarations and making them easier for application developers to use. The Spring docs summarise this as:
Starters are a set of convenient dependency descriptors that you can include in your application. You get a one-stop shop for all the Spring and related technologies that you need without having to hunt through sample code and copy-paste loads of dependency descriptors. For example, if you want to get started using Spring and JPA for database access, include the spring-boot-starter-data-jpa dependency in your project.
However, this does not mean that all dependencies must be declared via parents or starters so, if you are not using Spring Boot then you can declare a dependency without using a parent or a starter and what you have described in your question (declaring dependencies on 3 core Spring libraries) can be safely covered by simply depending on those 3 libraries explicitly. For example, just add the following to your your pom.xml:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.3.9.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>4.3.9.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>4.3.9.RELEASE</version>
<scope>test</scope>
</dependency>

Since you are going though the tutorials I'm assuming you are new to spring.
The folks at spring were nice enough to setup a site that generates projects.
It is very easy to use. I recommend trying that while learning. Download a few apps with the dependencies you want and look at how they are set up.
Once you are comfortable and want to dive deeper, read #glytching's answer again, it is very good.

Use spring-framework-bom if you don't use Spring Boot and need Spring Framework dependencies only:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-framework-bom</artifactId>
<version>4.3.9.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
In such case dependency would be without version was specified:
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
</dependency>
Also, yet another option exists if you use Spring Boot but you don't want to use spring-boot-starter-parent as parent artifact:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>1.5.9.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
See Spring Boot docs for more details. An important note from the docs:
Each release of Spring Boot is associated with a base version of the Spring Framework so we highly recommend you to not specify its version on your own.
It means that you should use Spring Framework version is defined for Spring Boot.

What is the difference between ${spring.version} and literal version number

I saw many tutorial some people use maven dependency such way
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${spring.version}</version>
</dependency>
and some people use maven dependency such way
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>4.3.3.RELEASE</version>
</dependency>
What is the main difference between <version>${spring.version}</version> and <version>4.3.3.RELEASE</version> in maven?

The notation of ${spring.version} is a POM variable. This means that somewhere in POM (or in one of parent POMs), you'll see a definition similar to this:
<spring.version>4.3.3.RELEASE</spring.version>
They both achieve the same end result, but using variables is a bit easier to maintain, especially if you use several artifacts sharing the same version. This way, when you choose to upgrade them, you only need to change the version in one place instead of once per artifact.

Do I need to download the dependencies that Spring need in Maven?

I am starting out with Spring and I am reading Pro Spring 2.5. On page 17 they talk about Spring dependencies and I wonder if I need to add this myself in the POM, or does the dependency I have added below do this? Such as CGLib, dom4j etc?
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>3.1.1.RELEASE</version>
</dependency>

You shouldn't need to. Maven will read the pom for spring-context and get any necessary dependencies that it has too, so you won't need to specifically put them in your own pom.
Check out this link it's really handy.

<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>3.1.1.RELEASE</version>
</dependency>
This will just instruct maven that the current POM in which this is declared is dependent on this artfact, so when you compile the app it would make it available for you in classpath

Trying to use Spring LDAP for coding

I am trying to use Spring LDAP for coding
<ldap-server ldif="classpath:my-ldap-clone.ldif" />
but I get this error
NoClassDefFoundError: org/apache/directory/server/core/DirectoryService
What am I doing wrong?

Using maven :
<dependency>
<groupId>org.apache.directory.server</groupId>
<artifactId>apacheds-all</artifactId>
<version>1.5.7</version>
</dependency>

If you are using Maven, these actually come from an optional dependency of spring-security-ldap.
Using apacheds-all is a bad idea because it embeds a lot of rather common dependencies, like slf4j and dom4j. You would easily get into classloader issues with it.
Instead, you should look inside the pom of the spring-security-ldap version your are using, for the apacheds optional dependencies, and copy them over to your pom without the <scope> and <optional> elements (unfortunately there is no better way to handle optional dependencies with Maven).
For instance, with spring-security-ldap 4.2.2, it would give:
<dependency>
<groupId>org.apache.directory.server</groupId>
<artifactId>apacheds-core</artifactId>
<version>1.5.5</version>
</dependency>
<dependency>
<groupId>org.apache.directory.server</groupId>
<artifactId>apacheds-core-entry</artifactId>
<version>1.5.5</version>
</dependency>
<dependency>
<groupId>org.apache.directory.server</groupId>
<artifactId>apacheds-protocol-ldap</artifactId>
<version>1.5.5</version>
</dependency>
<dependency>
<groupId>org.apache.directory.server</groupId>
<artifactId>apacheds-protocol-shared</artifactId>
<version>1.5.5</version>
</dependency>
<dependency>
<groupId>org.apache.directory.server</groupId>
<artifactId>apacheds-server-jndi</artifactId>
<version>1.5.5</version>
</dependency>
(it looks like it hasn't changed since at least 3.2)

Download ApcheDS from below link
http://directory.apache.org/ or get complete jar from here
I have used to work with Spring Security 3.0.5 with LDAP (Spring LDAP 1.3). That time i didn't met requirement of ApacheDS. Check your version of Spring Secuirty which may have dependency with ApacheDS.