This page describes the server software requirements for Weave.
Java
The Weave web application requires Java to run, but as part of the installation process a suitable Java runtime can be installed along with the rest of the Weave components. During the installation process you can choose to use an existing Java runtime for running Weave, if it meets the minimum requirements, or you can have the Weave installer install the bundled Java runtime. The Java runtime that's bundled with the release is 1.7 and is suitable for both Windows and Linux, but Weave will also work with Java 1.8.
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OpenJDK is currently not supported.
Java Licencing.
Cohga supplies version 7 of Java with Weave by default. This supplied version of Java 7 does not have updates enabled and is fixed at the version, as installed. Cohga has supplied Java 8 to some customers that need Java 8 to work with Esri using TLS 1.2 and above for their ArcGIS Online platform. The Java 8 version supplied by Cohga is build 191 and was downloaded in September 2018.
The Oracle JDK FAQ clearly states that if you download and use a version of Java prior to April 16, 2019, it is not affected by the new license agreement. See here: https://www.oracle.com/technetwork/java/javase/overview/oracle-jdk-faqs.html
Specifically these two sections:
What versions are available under the Binary Code License for Java SE (“BCL”)?
Oracle Java SE versions (including updates) released prior to April 16, 2019 are the only versions licensed under the BCL license.
What happens to the Oracle Java SE releases I downloaded under previous licenses, such as the BCL?
You may continue to use releases you have downloaded under the terms of the license under which you downloaded them. Legacy releases are still available in the Java Archives. Note that older versions of the JRE and JDK are provided to help developers debug issues in older systems. They are not updated with the latest security patches and are not recommended for use in production. Oracle strongly recommends that you remain on an up-to-date version of Java with the latest performance, stability and security updates.
Importantly, later releases of Weave will use the OpenJDK version of Java. This does not have the licence restrictions as does the Oracle version. If your site wants to run a more updated version of Oracle Java 8 then you will need to purchase a license from Oracle. In simple terms, the licence change introduced by Oracle in 2019 will not affect the running of your Weave system today, and not in the future.
Application Servers
Cohga supports the application servers listed on the page Supported Platforms, provided they are running on Windows, Linux, a UNIX-based operating system (such as NetBSD, FreeBSD, OpenBSD and Solaris). If you have no preference for a particular application server and wish to set up Weave for production purposes, we highly recommend installing our standalone version, which includes the Jetty application server.
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