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How to include libraries during war file built in spring project?

I have a spring project and it is running well. The problem is, whenever I perform a new deployment using the war file in tomcat, I need to manually copy the libraries in the lib folder. I am wondering if there is any way to add those libraries inside the war file so that every time I don't need to waste my time by copying the libraries in the server. It needs to be automatically included from the generated war file.

This answer depends on how you are building your WAR but I assume you are using one of the popular build tools for Java. Given that your war does not have a populated lib folder I'm assuming you have either not configured the right plugins for these build tools or you are compiling and managing your classpath from the command line like a madman. If the later is the case then I highly suggest you start using a build tool for your projects (All IDE's do this by default), if the former is the case I refer you to the individual pages for the plugins:
Maven:
https://maven.apache.org/plugins/maven-war-plugin/index.html
The war plugin does this by default.
Gradle: https://docs.gradle.org/current/userguide/war_plugin.html
The War plugin for Gradle also does this by default.
Ant: https://ant.apache.org/manual/Tasks/war.html
A glossary reading for the Ant tasks did not reveal if it did so by default but I'm assuming it does.

Difference between Jar and Plugin in Java and when to use them

What is the difference between Jar and Plugin in Java? Both looks the same by achieving the same purpose and when do use Jar and when do we use Plugin.

A plugin is an extension to Maven, something used to produce your artifact. Plugins are used only to make maven process successful. They are not directly connected to your application. plugins do not include in your last war/jar file for the service or client.
A dependency is a library that is needed by the application you are building, at compile and/or test and/or runtime time. the classes you used from jars will include in your final war/jar.
This will be helpful for you,
What is the difference in maven between dependency and plugin tags in pom xml?
Difference between plugin and external jar file

plug-in is a software component that adds a specific feature to any computer program.It specially use to customize any computer program.But .jar file is a java executable file which can only run on an environment which Java installed.

netbeans builds Maven projects jar file without dependent jar files

Could anyone would be so kind and explain how to make a single jar file with all maven dependencies in Netbeans Maven Java Application? In Eclipse user can Export to Runnable jar file and select Package required libraries into generated JAR, so all dependencies within project comes in created jar file. In Netbeans there is no such option.
I have checked other answers, but the only thing i understand is that I have to add code to Build.xml file which is not even in the project.

The last time I had to do this I used the Maven Shade Plugin. It allows you to create a single JAR file and also handles dependency clashes.
A simpler solution (which doesn't handle dependency clashes) is to use the Maven Assembly Plugin.
Note that these are pure Maven solutions which should work in any IDE.

Where to put Java libraries?

I'd like to know how I can add Java libraries to an Eclipse project on a development machine so that they can be added to an Eclipse project without causing errors when someone who has the library in a different location. For example, one developer might add an external JAR in C:\Java, but another might have the same JAR somewhere else. (Where's C:\Java on Mac OS?) I thought I might set the CLASSPATH environment variable, but I can't figure how to add an external JAR from the CLASSPATH environment variable. I'd like to do this so that it works with any workspace. Is this possible?
This is specifically for use with Anypoint Studio, but I think the same problem would exist with any Eclipse-based IDE.

In general, it's recommended to either embed JARs directly into the project, usually in a /lib folder of the project, as described here; or to use a tool like Gradle or Maven to manage dependencies, both of which have nice plugins to support their use in Eclipse.
Another alternative would be to use a Classpath Variable to refer to the JAR(s), which abstracts the physical location so that it can be set on a per-workspace basis.

I think the best way to add library to eclipse project is creating a directory - lib in your project directory. Then add the whole lib to you eclipse class path. You can follow these step to add a lib to class path -
Right click on project and select properties
Select Java Build Path
click Add Library and create User Library
Now add External Jars to this library create at step 3.
By this a .classpath file is crated in you project directory and the CLASSPATH problem will be resolved

I guess the best way to do that would be using Maven, or a similar build system that can construct your Classpath base on dependencies.
You can add the dependencies to your pom and having the jars in your local maven repository in the machine.
http://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html
Because in any other approach you will need to maintain everything manually, and when having different OS the path will change.

Eclipse is just the IDE that will help to write code and assemble the project (JAR, WAR, ... ). You can add your external jars from wherever you want, and when you want to export your project (with eclipse) you may choose to package the required libraries into the jar.
However, I recommend always to use maven (or something like ) to avoid this kind of problems.

Part1:(import .jar file as library in Eclipse)
You make a new project to Eclipse(name:Project1)
When you open it you see JRE System Library[java version something]
1.right click on JRE System Library
2.Go->Build Path->Configure Build Path
3.You can see (Up right Corner the button[add jars or add external jars]
*Here i advise you to choose the first(add jars) but..
*First copy(or move) the (name).jar inside the project((example):Project 1)
*Now you can add it with the button(add jars).
*In this way when you finish your project the (name).jar will be
imported inside the project(If you export it as a .jar from Eclipse)
..Now you can call any method of (name).jar just(import it into the class
you want to use and call it)

How could I have Eclipse export files into a different location than their source?

I am writing a Bukkit plugin in Eclipse in which I separate different functions into different packages and export each package as its own jar file.
However, I would still like to keep these packages in the same project, rather than separating them into different Eclipse projects. These plugins each have files which must be in the root of the jar file, such as plugin.yml. I have moved each jar's files into their respective packages, but these files are put into plugin.jar\com\Preston159\plugin rather than in the root of the jar file (plugin.jar\), causing the plugin not to work.
Does Eclipse have any function to make these files automatically compress into the root of the jar file even though they are contained within the package in the source, or, is this something that I could solve by using Maven? My current solution to this problem is to move the files manually after exporting the jar, but this is becoming increasingly annoying.
EDIT:
The project builder XML I ended up using to complete this task can be found here

You would need to use a Build Tool. There are several supported by Eclipse. Ant and Maven are now built-in, but there are several build tools that run directly within Eclipse, but Eclipse can also be configured to run an external build tool as well.
Do a quick search on build.xml for examples of ANT build jobs.
Unless you're specifically required to use MAVEN for continuous integration, etc. then what you want to accomplish would be easily done with ANT.