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ANT to Maven Migration. Maven alternative to build.xml

Background:
I am working on a open source tool called draw.io which is based on ANT build system and uses Java servelets to handle request. I am supposed to migrate it to spring boot with using same front end files. I put those files in static folder and tried to build the project. I figured that the front end js files were not getting build (i.e. were not getting converted to app.min.js, which is the main entry point for front end files), in the process and none of the js changes were getting reflected in the file.
I figured that this process was mentioned in build.xml as part of various steps which is ANT specific configuration. Now, I have to achieve the same in maven as the migration process.
How do we convert build.xml to maven or what is the maven alternative of achieving the tasks mentioned in the build.xml as part of build process?
This is the high level view of build.xml:->
I am also providing the link of build.xml here...
Please provide me with some direction.

Before migrating to maven, I hope you understand why you are moving to maven from ant.
You should try for finding alternative plugins for the relevant ant task. The below plugin might do what you are trying to achieve in ant
<plugin>
<groupId>com.github.blutorange</groupId>
<artifactId>closure-compiler-maven-plugin</artifactId>
<version>2.16.0</version>
<configuration>
<!-- Base configuration for all executions (bundles) -->
<baseSourceDir>${project.basedir}/src/main/resources</baseSourceDir>
<baseTargetDir>${project.build.directory}/generated-resources</baseTargetDir>
</configuration>
<executions>
<!-- Process all files in the "includes" directory individually-->
<execution>
<id>default-minify</id>
<configuration>
<encoding>UTF-8</encoding>
<sourceDir>includes</sourceDir>
<targetDir>includes</targetDir>
<includes>**/*.js</includes>
<skipMerge>true</skipMerge>
<closureLanguageOut>ECMASCRIPT5</closureLanguageOut>
</configuration>
<goals>
<goal>minify</goal>
</goals>
<phase>generate-resources</phase>
</execution>
</executions>
</plugin>
More details about the plugin : closure-compiler-maven-plugin
There are few cases during my ant to maven migration, I came across some custom tasks which I was not able to find appropriate plugins.
I used maven-antrun-plugin which keeps existing ant tasks in maven.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-antrun-plugin</artifactId>
<version>1.8</version>
<executions>
...
</executions>
</plugin>
More details about how to use the maven antrun plugin : See this
tutorial

For Maven, you need a pom.xml. There you need to define and configure the plugins you need. If you have a specific procedure written in Ant that you want to reuse, you can call it with the Maven Antrun Plugin.
Generally, Maven is very different from Ant. You don't write procedural code, but configure plugins running in a lifecycle.

Spring boot Maven use same jar with different version in multi module project

We have quite a strange requirement.
Spring boot with multiple project
xbean is old version of xmlbeans apache jar
We want to use both
xbean old jar with some custom changes in the same jar
latest xmlbeans apache jar
we have current implementation as
Main() -
|- XLSImportProject project- which requires latest jar for reading xlsx file
|- B project - which requires old jar for custom operation
|- C project - also require old jar for custom operation
If we give maven priority to xbean old jar then we will get exception as
org.apache.poi.ooxml.POIXMLException: org.apache.xmlbeans.XmlOptions.setEntityExpansionLimit(I)Lorg/apache/xmlbeans/XmlOptions;
at org.apache.poi.ooxml.POIXMLFactory.createDocumentPart(POIXMLFactory.java:66)
at org.apache.poi.ooxml.POIXMLDocumentPart.read(POIXMLDocumentPart.java:648)
at org.apache.poi.ooxml.POIXMLDocument.load(POIXMLDocument.java:180)
at org.apache.poi.xssf.usermodel.XSSFWorkbook.<init>(XSSFWorkbook.java:286)
at org.apache.poi.xssf.usermodel.XSSFWorkbookFactory.createWorkbook(XSSFWorkbookFactory.java:83)
at org.apache.poi.xssf.usermodel.XSSFWorkbookFactory.createWorkbook(XSSFWorkbookFactory.java:130)
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.poi.ss.usermodel.WorkbookFactory.createWorkbook(WorkbookFactory.java:314)
at org.apache.poi.ss.usermodel.WorkbookFactory.createXSSFWorkbook(WorkbookFactory.java:296)
at org.apache.poi.ss.usermodel.WorkbookFactory.create(WorkbookFactory.java:214)
at org.apache.poi.ss.usermodel.WorkbookFactory.create(WorkbookFactory.java:180)
If we give maven priority to latest xmlbeans then it will be errors as:
Exception in thread "Thread-14" java.lang.NoSuchMethodError: org.apache.xmlbeans.XmlObject.getParent()Lorg/apache/xmlbeans/XmlObject;
We have to use old xbean jar in sub project and latest xmlbeans jar in other project.
But Spring will always the jar which is define first in dependency.

That looks like a classical classloader customization problem. I wouldn't go down that road. Best suggestion would be
create your own jar with all dependencies (tricky since you will face the problems of backward compatibility). Take a look here for repackaging jars.
Break away the multi module project into different projects with each set of projects using a particular dependency.

Take a look at Maven shade plugin. It rename the packages if required based on the content of the jar. Create Uber jar for your main application using shade plugin.
Shade plugin configuration:
<project>
...
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>3.2.1</version>
<configuration>
<!-- put your configurations here -->
</configuration>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
...
</project>

Maven + Tycho, adding Maven dependencies

We have an Eclipse Plugin which we build using Maven and Tycho. Currently
however, we still provide all project dependencies through a bunch of manually
added JAR files and not by Maven. This is due to the following reasons: (1) The
dependencies are not available through a standard Eclipse update site (at least
not in a current version), (2) the dependencies are not available as bundles.
The biggest part of these dependencies are the Selenium libraries (API, Remote,
browser-specific libs and their transitive dependencies, such as Guava, etc.)
I've wasted hours, trying to pull those dependencies during our Maven build.
Following this SO question, I tried the p2-maven-plugin, created an update
site with our dependencies which I added to my Eclipse target platform. However,
during runtime, classes, which are referenced across different JARs could not be
loaded (I assume, from my very limited OSGi knowledge, because some
necessary information was missing in the MANIFEST.MF files). Here's an example
of the issue, when trying to create a RemoteWebDriver, which uses the
DesiredCapabilities class (both classes in different bundles):
Exception in thread "Thread-8" java.lang.NoClassDefFoundError: org/openqa/selenium/remote/DesiredCapabilities
at org.openqa.selenium.remote.RemoteWebDriver.startSession(RemoteWebDriver.java:243)
at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:126)
at org.openqa.selenium.remote.RemoteWebDriver.<init>(RemoteWebDriver.java:153)
…
Caused by: java.lang.ClassNotFoundException: org.openqa.selenium.remote.DesiredCapabilities cannot be found by org.seleniumhq.selenium.remote-driver_2.45.0
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:439)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:352)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:344)
at org.eclipse.osgi.internal.loader.ModuleClassLoader.loadClass(ModuleClassLoader.java:160)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 7 more
Is there anything I still need to take care of, when using the p2-maven-plugin? The relevant parts of the pom.xml looked like this:
<plugin>
<groupId>org.reficio</groupId>
<artifactId>p2-maven-plugin</artifactId>
<version>1.1.1-SNAPSHOT</version>
<executions>
<execution>
<id>default-cli</id>
<configuration>
<artifacts>
<artifact>
<id>org.seleniumhq.selenium:selenium-remote-driver:2.45.0</id>
</artifact>
</artifacts>
</configuration>
</execution>
</executions>
</plugin>

Couldn't get it to work, so we're now using the maven-dependency-plugin with the copy-dependencies, which we execute during the Maven initialize phase to pull all necessary dependencies (contrary to my initial feeling, this can be combined with the pom.xml using the eclipse-plugin packaging and the "manifest first" approach). The relevant part looks like this:
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>2.10</version>
<executions>
<execution>
<id>copy-dependencies</id>
<phase>initialize</phase>
<goals>
<goal>copy-dependencies</goal>
</goals>
<configuration>
<includeScope>runtime</includeScope>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
The Maven dependencies are then copied to target/dependency.
Only little issue: The Bundle-ClassPath in the MANIFEST.MF needs to be manually updated in case the name of a JAR file changes when updating Maven dependencies (e.g. commons-io-2.4.jar becomes commons-io-2.5.jar).
[edit] Revisiting this answer in regards to the last sentence above: The version numbers can be conveniently stripped through the following option: <stripVersion>true</stripVersion>. This means, the above library will be renamed to commons-io.jar and thus no paths need to be updated when a version number changes.

Another possibility:
Some jar files may be broken (if you're using Eclipse, it's commonplace hibernate-commons-annotations-4.0.1.Final.jar; invalid LOC header (bad signature)? ). To check this possibility, try manually opening the jar to see if it's okay.

I also build an Eclipse plugin with Maven and Tycho. I have the same problem: the bundle org.eclipse.team.svn.core and org.eclipse.team.svn.ui are not available through a standard Eclipse update site.
Maybe you can try this to solve this kind of problem:
In Dependencies, find the box Automated Management of
Dependencies.
Add the wanted plugin using Add...
Choose Analyze code and add dependencies to the MANIFEST.MF via: Import-Package
Click on Add Dependencies so that you find required packages in the box Imported Packages nearby.
Then you can run the Maven build.

How to run a multiple module project using Maven on NetBeans [duplicate]

I am new to maven. So I have a project with pom.xml file. So I ran that with maven and the build was successful. I have glassfish. Glassfish is already running separately. So now what is the next step to run the project with Glassfish? My IDE is eclipse.

You have to first tell Maven to build the WAR, check out this plugin for that: http://maven.apache.org/plugins/maven-war-plugin/.
Then you need to tell maven how to deploy to glassfish, you can either configure a Maven execution plugin to do this (see here: https://www.mojohaus.org/exec-maven-plugin/). Or you can look around for a custom plugin devoted to integrating maven with glassfish. This one looks promising, but I have not used it: http://maven-glassfish-plugin.java.net/.
Maven provides a lot of basic functionality out of the box, but most of the cooler stuff with build automation is done through plugins.
Update
Just updating to add a very simple Pom that will do a auto-deployment. Note: if you just run a "mvn clean install", with the packaging set to 'war', maven will build the .war file for you and place it in the target/ folder. You can take this and deploy it to glassfish manually if you just want to get started.
Below is part of a very simple pom that uses the Maven execution plugin to auto-deploy to glassfish as a function of the build:
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<executions>
<execution>
<goals>
<goal>exec</goal>
</goals>
<phase>install</phase>
</execution>
</executions>
<configuration>
<executable>${path-to-asadmin-util}</executable>
<arguments>
<argument>deploy</argument>
<argument>--user=${username}]</argument>
<argument>--passwordfile=${password-file}</argument>
<argument>--host=localhost</argument>
<argument>--port=4848</argument>
<argument>target/${project.name}</argument>
</arguments>
</configuration>
</plugin>
</plugins>
</build>
This basically just calls the deploy command on the glassfish asadmin utility[1]. You need to fill in the following variables:
${path-to-asadmin-util} --> this is the path to your asadmin utility
(normally in the glassfish_home/bin)
${username} --> glassfish admin username
${password-file} --> password file for logging into glassfish
admin[2]
${project.name} --> name of your war
If you want to get more complicated I suggest taking a look at this thread: GlassFish v3 and glassfish-maven-plugin (Mac).
[1] - http://docs.oracle.com/cd/E18930_01/html/821-2433/deploy-1.html#SJSASEEREFMANdeploy-1
[2] - http://docs.oracle.com/cd/E18930_01/html/821-2435/ghgrp.html#ghytn

Additonnaly, you should have a glance at this StackOverflow thread, dealing with maven deployement in glassifsh : https://stackoverflow.com/a/1836691/1047365.
For further understanding of Maven, you should REALLY read this (free) book : http://www.sonatype.com/books/mvnref-book/reference/. This is THE reference for Maven.
We can explain you what Maven is doing, producing, etc ... but Sonatype made a great work and you'll probably learn more reading it than we could ever do !
Regards.

I found this tutorial useful: http://tshikatshikaaa.blogspot.com/2012/05/introduction-to-maven-concepts-crash.html

Issue setting the class path in Maven exec plugin when running a Main Class

I have embedded Jetty in my application. In order to automatically execute my integration tests on my build server I'd like Maven to start my application in the pre-integration-test phase. The integration tests are in another project than the application te be tested, because the tests are of a quite complex nature and should be seperated from production code.
I have tried to set up my application using the Maven exec plugin, but keep running into ClassNotFoundErrors. I use the maven-dependency-plugin to copy all dependencies to target/lib/. Until now, I haven't been able to figure out how to tell the exec plugin to add that lib folder to the class path.
This is my current exec plugin configuration:
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.2.1</version>
<executions>
<execution>
<id>default-cli</id>
<phase>pre-integration-test</phase>
<goals>
<goal>java</goal>
</goals>
<configuration>
<mainClass>com.zertificon.managementCenter.adminUi.server.WebApp</mainClass>
<!-- this does not work: -->
<classpath>${project.build.directory}/${libFolder}/</classpath>
</configuration>
</execution>
</executions>
</plugin>
The WebApp class I am trying to run originates from another Project and is installed in the local repository. I would highly apreciate any help.

Found the error: I have been using Jetty together with a Selenium Library that itself bundles Jetty, too. This lead to a wrong Jetty Version being loaded wich gave me class not found errors. Go figure.