requirements.html

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	<h1 class="title">Requirements</h1>
	<div class="entry">
	Instructions on downloading and installing Repast Simphony on various platforms
	can be found in the <a href="https://repast.github.io/quick_start.html">Quick Start Guide</a>.
	Repast Simphony is a Java application and requires at least Java 8 to be installed. We currently 
	recommend Java 11. If you do not have Java installed, the following options are 
	suggested:<br>
	<ul>
		<li>Windows users may choose to install the Java 11 Development Kit 
		(JDK) included with the Repast Simphony Windows installer.  This will install
		Java as a folder within the Repast installation location and will not 
		interfere with existing Java or Repast installations.</li>
		
		<li>macOS, linux, and Windows users may download a Java 11 JDK from 
		<a href="https://adoptium.net">Adoptium</a> (formerly AdoptOpenJDK). Select <i>Temurin 11 (LTS)</i>. 
		<br>
		<ul>
			<li><b>macOS users</b> should double click on the downloaded file to install the package.</li>
			
			<li><b>Windows users</b> should unzip the downloaded file and copy the folder
			to any convenient location.  The OpenJDK installers no longer set the
			system PATH or JAVA_HOME, so this needs to be done manually.
			<a href="https://stackoverflow.com/questions/52511778/how-to-install-openjdk-11-on-windows">
			This post on Stack Overflow</a> desribes how to configure OpenJDK for
			Windows.</li>
			
			<li><b>Linux users</b> should try the system package manager to download 
			and install an appropriate JDK. Alternatively, the OpenJDK 11 tarball can be
			extracted an manually installed on linux.  For example, the 
			<a href="https://dzone.com/articles/installing-openjdk-11-on-ubuntu-1804-for-real">
			Instructions for installing OpenJDK on Ubuntu 1804</a>.</li>
		</ul>
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	<br>
	
	<h3 class="title">Why OpenJDK / Adoptium?</h3>
	<div class="entry">
	In the past users have typically downloaded a Java Development Kit (JDK) 
	distribution from Oracle and used it for free. These releases were built 
	with the <a href="https://openjdk.java.net">OpenJDK</a> source with some 
	non-essential proprietary extras added. However, with the release of Java 11, 
	Oracle's JDK is no longer free for commercial use. For this reason, we are 
	recommending users install an <a href="https://adoptium.net">Adoptium</a> (formerly AdoptOpenJDK)
	release built from OpenJDK source. Java 11 has been designated a long term 
	support (LTS) release and as such will continue to be supported by the OpenJDK 
	team with bug and security fixes for 4 years. The Adoptium project provides 
	JDK binaries for all of the major platforms built from the OpenJDK source 
	using a robust build and test system.<br>

	<br>
	See <a href="https://blog.joda.org/2018/09/time-to-look-beyond-oracles-jdk.html">here</a> for
	additional information on Oracle and OpenJDK.
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