+though you may need to fiddle with the `install4j` and `copyInstall4jTemplate` tasks
+in `build.gradle` file to point to your installation of *install4j* and also to bundled
+JREs if you want to bundle those into the installers.
+
+If you want more details, get in touch on our development mailing list <jalview-dev@jalview.org>.
+Sign up at <http://www.compbio.dundee.ac.uk/mailman/listinfo/jalview-dev>.
+
+
+
+
+## Gradle properties
+
+There are a lot of properties configured in `gradle.properties` which we strongly recommend
+being left as they are unless you have a specific problem with the build process.
+
+There are a few gradle properties you might want to set on the command line with the
+`-P` flag when building a version of Jalview with specific requirements:
+
+#### `JAVA_VERSION`
+This changes the *target* java bytecode version
+> NOTE that you will need to use a Java 11 (or greater) JDK Java compiler to build
+Jalview for any byte-code target version.
+
+Valid values are `11` and `1.8`.
+
+e.g.
+
+```bash
+gradle shadowJar -PJAVA_VERSION=1.8
+```
+
+When using `-PJAVA_VERSION=1.8` the libraries from `j8lib` (instead of `j11lib`) will be used in the compile
+and runtime classpath and also used in the `makeDist` build step. Where a Java version of `11` is used in folder and file names, it will
+instead use `1.8`. Also if you are building installer packages with *install4j* the
+package builder will look for JRE 1.8 bundles to package in the installers.
+
+> Note that continued development of Jalview will assume a Java 11+ runtime environment,
+the 2.11.0 release will run under a Java 1.8 JRE with a few minor features disabled.
+
+#### `CHANNEL`
+This changes the `appbase` setting in `getdown.txt` (`appbase` is where the getdown launcher
+looks to see if there's an updated file) to point to a particular Jalview channel or some other appropriate
+place to look for required files. If the selected channel type requires the getdown `appbase` to be a local
+directory on the filesystem (instead of a website URL) then a modified version of the `getdown-launcher.jar` will
+be used to allow this. The two versions of the `getdown-launcher.jar` can be found in `getdown/lib`.
+Note that the DEVELOP and RELEASE channels will normally use a getdown-launcher.jar that *does not* allow the
+`file://` scheme to be used in the appbase.
+
+Some other variables used in the build process might also be set differently depending on the value of `CHANNEL`
+to allow smooth operation of getdown in the given context.
+
+There are several values of `CHANNEL` that can be chosen, with no choice leading to a default of `LOCAL`.
+Here's what they're for and what they do:
+
+* `LOCAL`: This is for running the compiled application from the development directory and used by default.
+ It will set
+ - `appbase` as `file://PATH/TO/YOUR/DEVELOPMENT/getdown/website/JAVA_VERSION`
+ (e.g. `file://home/user/git/jalview/getdown/website/11`)
+ - application subdir as `alt`
+ - Getdown launcher can use a `file://` scheme appbase.
+ - Compile jalview with `gradle getdown` or `gradle shadowJar`
+ - Run Jalview on the command line without using the installers with,
+ Using getdown, e.g. `java -jar ./getdown/files/11/getdown-launcher.jar ./getdown/files/11 jalview`
+ or using the shadowJar with, e.g. `java -jar ./build/libs/jalview-all-TEST-j11.jar`
+* `BUILD`: This is for creating an appbase channel on the build server by an automatic or manually started build.
+ It will set
+ - `appbase` as `https://builds.jalview.org/browse/${bamboo_planKey}/latest/artifact/shared/getdown-channel/JAVA_VERSION`
+ Note that bamboo_planKey should be set by the build plan with `-Pbamboo_planKey=${bamboo.planKey}`
+ - application subdir as `alt`
+ - Getdown launcher cannot use a `file://` scheme appbase.
+* `DEVELOP`: This is for creating a `develop` appbase channel on the main web server. This won't become live until the actual getdown artefact is synced to the web server.
+ It will set
+ - `appbase` as `http://www.jalview.org/getdown/develop/JAVA_VERSION`
+ - application subdir as `alt`
+ - Getdown launcher cannot use a `file://` scheme appbase.
+* `SCRATCH-NAME`: This is for creating a temporary scratch appbase channel on the main web server. This won't become live until the actual getdown artefact is synced to the web server. This is meant for testing an over-the-air update without interfering with the live `release` or `develop` channels. The value of `NAME` can be any "word-character" [A-Za-z0-9\_]
+ It will set
+ - `appbase` as `http://www.jalview.org/getdown/SCRATCH-NAME/JAVA_VERSION`
+ - application subdir as `alt`
+ - Getdown launcher cannot use a `file://` scheme appbase.
+* `TEST-LOCAL`: Like `SCRATCH` but with a specific `test-local` channel name and a local filesystem appbase. This is meant for testing an over-the-air update on the local filesystem. An extra property `LOCALDIR` must be given (e.g. `-PLOCALDIR=/home/user/tmp/test`)
+ It will set
+ - `appbase` as `file://${LOCALDIR}`
+ - application subdir as `alt`
+ - Getdown launcher can use a `file://` scheme appbase.
+* `TEST-RELEASE`: Like `SCRATCH` but with a specific `test-release` channel name. This won't become live until the actual getdown artefact is synced to the web server. This is meant for testing an over-the-air update without interfering with the live `release` or `develop` channels.
+ It will set
+ - `appbase` as `http://www.jalview.org/getdown/test-release/JAVA_VERSION`
+ - application subdir as `alt`
+ - Getdown launcher cannot use a `file://` scheme appbase.
+* `RELEASE`: This is for an actual release build, and will use an appbase on the main web server with the main `release` channel name. This won't become live until the actual getdown artefact is synced to the web server.
+ It will set
+ - `appbase` as `http://www.jalview.org/getdown/release/JAVA_VERSION`
+ - application subdir as `release`
+ - Getdown launcher cannot use a `file://` scheme appbase.
+* `ARCHIVE`: This is a helper to create a channel for a specific release version, and will use an appbase on the main web server with a specific `archive/JALVIEW_VERSION` channel name. This won't become live until the actual getdown artefact is synced to the web server.
+You must also specify an `ARCHIVEDIR` property that points to an earlier version of Jalview with a `dist` directory containing the required jar files. This should create a getdown structure and digest with the older jar files.
+ It will set
+ - `appbase` as `http://www.jalview.org/getdown/archive/JALVIEW_VERSION/JAVA_VERSION`
+ - application subdir as `alt`
+ - Getdown launcher cannot use a `file://` scheme appbase.
+* `ARCHIVELOCAL`: Like `ARCHIVE` but with a local filesystem appbase for local testing.
+You must also specify an `ARCHIVEDIR` property that points to an earlier version of Jalview with a `dist` directory containing the required jar files. This should create a getdown structure and digest with the older jar files.
+ It will set
+ - `appbase` as `file://PATH/TO/YOUR/DEVELOPMENT/getdown/website/JAVA_VERSION` (where the old jars will have been copied and digested)
+ - application subdir as `alt`
+ - Getdown launcher can use a `file://` scheme appbase.
+
+e.g.
+```bash
+gradle getdown -PCHANNEL=SCRATCH-my_test_version
+```
+
+**New `CHANNEL` appearance features 2020-12-10**
+There are now differing cosmetics for different channels, including application icons, Getdown splashscreen,
+About splashscreen, Installer backgrounds, application name. This is controlled by the files in
+```
+utils/channels
+```
+In `utils/channels` there are different directories for the different channels. Currently there are directories for
+`default`, `develop`, `release`, `test-release`, `jalviewjs` and `jalviewjs-release`. If a specified `CHANNEL` is not one of `DEVELOP`, `RELEASE`, `TEST-RELEASE`, `JALVIEWJS`, `JALVIEWJS-RELEASE`
+then it will use the `default` directory.
+
+Inside the `utils/channels/<channelname>` directory are:
+- a file `channel_gradle.properties`. This will be used by the `build.gradle` script (i.e. any gradle build) to *override* the values found in `gradle.properties`.
+- an `images` directory used to store different images referred to in this channels's `channel_gradle.properties`.
+- a `resources` directory which is merged into the javliew.jar's own resources directory. Importantly it contains a `channel.props` file and another `images` dir which contains properties and images used by the application (in `jalview.util.ChannelProperties`), such as icon files or banner images, and the `app_name` property used as the display name for the application (e.g. "Jalview Develop") inside the application code. Please see the `getProperty` and `getImage` methods in `jalview.bin.ChannelProperties` to access these channel based resources.
+
+
+#### JALVIEW_VERSION and the RELEASE file
+Any Jalview build will include the value of JALVIEW_VERSION in various places, including the 'About' and Jalview Desktop window title, and in filenames for the stand-alone executable jar. You can specify a custom version for a build via the JALVIEW_VERSION property, but for most situations, JALVIEW_VERSION will be automatically configured according to the value of the CHANNEL property, using the `jalview.version` property specified in the RELEASE file:
+ - `CHANNEL=RELEASE` will set version to jalview.version.
+ - `CHANNEL=TEST or DEVELOP` will append '-test' or '-develop' to jalview.version.
+ - `CHANNEL=JALVIEWJS` will use the `channel.props` found in `utils/channels/jalviewjs` but otherwise uses `LOCAL` settings.
+ - `CHANNEL=JALVIEWJS-RELEASE` uses a symbolic link to `utils/channels/jalviewjs` but otherwise uses `RELEASE` settings.
+
+It is also possible to specify a custom location for the RELEASE file via an optional JALVIEW_RELEASE_FILE property.
+
+#### `install4jMediaTypes`
+If you are building *install4j* installers (requires *install4j* to be installed) then this property specifies a comma-separated
+list of media types (i.e. platform specific installers) *install4j* should actually build.
+
+Currently the valid values are
+`linuxDeb`,
+`linuxRPM`,
+`macosArchive`,
+`unixArchive`,
+`unixInstaller`,
+`windows`
+
+The default value is all of them.
+
+e.g.
+```bash
+gradle installers -PJAVA_VERSION=1.8 -Pinstall4jMediaTypes=macosArchive
+```
+
+To get an up-to-date list of possible values, you can run
+
+```bash
+perl -n -e 'm/^\s*<(\w+)[^>]*\bmediaFileName=/ && print "$1\n";' utils/install4j/install4j_template.install4j | sort -u
+```
+in the `jalview` root folder.
+
+## Enabling Code Coverage with OpenClover
+
+Bytecode instrumentation tasks are enabled by specifying 'true' (or just a non-whitespace non-numeric word) in the 'clover' property. This adds the 'openclover' plugin to the build script's classpath, making it possible to track code execution during test which can be viewed as an HTML report published at build/reports/clover/index.html.
+
+```gradle -Pclover=true test cloverReport```
+
+#### Troubleshooting report generation
+
+The build forks a new JVM process to run the clover report generation tools (both XML and HTML reports are generated by default). The following properties can be used to specify additional options or adjust JVM memory settings. Default values for these options are:
+
+##### JVM Memory settings - increase if out of memory errors are reported
+
+```cloverReportJVMHeap = 2g```
+
+##### -Dfile.encoding=UTF-8 is an essential parameters for report generation. Add additional ones separated by a space.
+
+```cloverReportJVMArgs = -Dfile.encoding=UTF-8```
+
+##### Add -v to debug velocity html generation errors, or -d to track more detailed issues with the coverage database
+
+```cloverReportHTMLOptions = ```
+
+##### -v for verbose, -d for debug level messages (as above)
+
+```cloverReportXMLOptions = ```
+
+
+_Note_ do not forget to include the -Dfile.encoding=UTF-8 option: this is essential for some platforms in order for Clover to correctly parse some Jalview source files that contain characters that are UTF-8 encoded.
+
+## Setting up in Eclipse IDE
+
+### Installing Eclipse IDE
+
+We develop in Eclipse, and support settings to develop and save Jalview source code
+in our preferred style. We also support running the Jalview application, debugging
+and running tests with TestNG from within Eclipse.
+
+To get Jalview set up as a project in Eclipse, we recommend using at least the 2020-03
+version of Eclipse IDE for Java Developers which you can download from the Eclipse
+website: <https://www.eclipse.org/downloads/>. Since Eclipse 2020-03 you are encouraged to use the Eclipse Installer (see the Eclipse Downloads page).
+In the installer, when given a choice of packages for Eclipse you should choose the "Eclipse IDE for Enterprise Java Developers" package.
+
+![](./images/eclipse_installer.png "Eclipse Installer screenshot")
+
+Once Eclipse is installed, we also recommend installing several plugins from the Eclipse Marketplace.
+
+Some of these should already be installed with the Enterprise Java Developer package:
+
+1. Buildship Gradle Integration 3.0 (or greater)
+1. EclEmma Java Code Coverage
+1. Egit - Git Integration for Eclipse
+
+To install the others, launch Eclipse, and go to Help->Eclipse Marketplace...
+
+Search for and install:
+
+1. Groovy Development Tools 3.4.0 (or greater)
+1. Checkstyle Plug-in (optional)
+1. TestNG for Eclipse (optional -- only needed if you want to run tests from Eclipse)
+
+> At time of writing, TestNG for Eclipse does not show up in the Eclipse Marketplace
+as the latest released version does not install in Eclipse 2020-03.
+However, you can install a working release of TestNG for Eclipse by going to
+>
+> Help->Install New Software...
+>
+> and entering
+>
+> `TestNG Release - https://dl.bintray.com/testng-team/testng-eclipse-release`
+>
+> into the *Work with* box and click on the *Add...* button.
+>
+> Eclipse might pause for a bit with the word *Pending* in the table below at this point, but it will eventually list TestNG with
+a selection box under the *Name* column.
+>
+> Select *TestNG* and carry on through the
+install process to install the TestNG plugin.
+
+After installing the plugins, check that Java 11 is set up in Eclipse as the default JRE (see section [Java 11 compliant JDK](#java-11-compliant-jdk)).
+
+To do this go to Preferences (Eclipse->Preferences in macOS, File->Preferences
+on Windows or Window->Preferences on Linux) and find
+
+Java -> Installed JREs
+
+If your Java 11 installation is not listed, click on
+
+*Add* -> Standard VM -> *Next*
+
+and enter the JRE home. You can browse to where it is installed. Give it a name (like "AdoptOpenJDK 11"). Select this JDK
+as the default JRE and click on *Apply and Close*.
+
+
+You can now import Jalview.
+
+### Importing Jalview as an Eclipse project
+
+#### Importing an already downloaded git repo
+
+If you have already downloaded Jalview using `git clone` then you can import this folder into Eclipse directly.
+
+__Before importing the cloned git repo you must create the Eclipse project files.__ You can do this by either running
+
+`gradle eclipse`
+
+or
+
+Unzipping the file `utils/eclipse/eclipse_startup_files.zip` in the base repo directory (`jalview`)
+
+It is important to import
+Jalview as a Gradle project (not as a Java project), so go to
+
+File->Import...
+
+find and select
+
+Gradle->Existing Gradle Project
+
+and then click on the *Next* button.
+
+In the following options, it is the __Project Root Directory__ you should set to be the
+`jalview` folder that git downloaded. Then you can click on the *Finish* button.
+
+#### Using Eclipse IDE to download the git repo
+
+If you don't have git as a command line tool or would prefer to work entirely within Eclipse IDE then
+Eclipse's eGit plugin can set up a git repo of the jalview source. Go to
+
+File->Import...
+
+Find and select
+
+Git->Projects from Git
+
+and then click on the *Next* button.
+
+Then select Clone URI and click on *Next*.
+
+In the next window (Source Git Repository) you should put the `git clone` URL in the text box labelled `URI`. If you have a Jalview developer account (with a username and password for the Jalview git repository) then you should enter
+`https://source.jalview.org/git/jalview.git`.
+If you do not have a Jalview developer account then you should enter
+`http://source.jalview.org/git/jalview.git`.
+You will not be able to push any of your changes back to the Jalview git repository. However you can still pull all branches of the Jalview source code to your computer and develop the code there.
+> You can sign up for a Jalview developer account at <https://source.jalview.org/crucible/>
+
+If you have a Jalview developer account, enter the username and password and decide if you want to use Eclipse's secure storage. If you don't have an account you can leave the Authentication section blank.
+
+![Eclipse eGit connection configuration](./images/eclipse_egit_connection.png)
+
+Click on the *Next* button.
+
+The next window (Branch Selection) gives a list of the many Jalview branches, which by default will be all checked. You probably only want to download one branch (you can always download others at a later time). This is likely to be the `develop` branch so you can click on the *Deselect All* button, find the `develop` branch (the filter text helps), select that, and then click on the *Next* button.
+
+Choose a directory to your copy of the git repo in, and leave the other options as they are and click on the *Next* button. The next stage may take a minute or two as it checks out the selected branch(es) from the Jalview git repository.
+
+When it has finished it is important to select __Import as general project__ and then click on *Next*.
+> Ideally there would be an _Import as gradle project_ here but there isn't -- we'll sort that out later.
+
+![Eclipse eGit import choice](./images/eclipse_egit_import.png)
+
+Click on the *Next* button.
+
+You can change the project name here. By default it will show as __jalview__ which is fine unless you have another instance of the a Jalview project also called jalview, in which case you could change this project's name now to avoid a conflict within Eclipse.
+
+Click on *Finish*!
+
+However, we haven't finished...
+
+You should now see, and be able to expand, the jalview project in the Project Explorer. We need to tell eclipse that this is a Gradle project, which will then allow the Eclipse Buildship plugin to automatically configure almost everything else!
+
+Right click on the project name (jalview) in the Project Explorer and find Configure towards the bottom of this long context menu, then choose Add Gradle Nature.
+
+![Eclipse Add Gradle Nature](./images/eclipse_add_gradle_nature.png)
+
+The project should now reconfigure itself using the `build.gradle` file to dynamically set various aspects of the project including classpath.