MapTool 1.5 Comes Bundled with Java
MapTool 1.5 now comes bundled with Java so there’ll be no more struggling with Java versions or Java upgrades. You also don’t go through a launcher. Those settings have moved to the Edit->Preferences->Startup tab.

From here you set your maximum, minimum, and stack size memory for MapTool. This requires a MapTool restart after clicking OK. So, for a 4GB max memory and a 2 GB minimum memory setting you would enter 4G and 2G. The input honors G, M, and K for Gigabytes, Megabytes, and Kilobytes for memory sizes.
Note: we recommend setting the max and min values to the same value to minimize Java garbage collection. Also note that if you don’t set these values then the Java Virtual Machine will compute them based on your computer’s memory.
Note: you can still run the jar file directly via the java -jar command but if you do so you won’t have access to the startup tab and will need to set those parameters on the command line as you did in the past. (see comments for additional information)
Update: If you put settings in that break MapTool, you can reset them back to their default. Please see Resetting MapTool JVM Settings for more detail.
Excited about the new functionality? Let’s discuss in the comments below or on one of our many social outlets.
You can download available versions of MapTool from GitHub.
All users running versions prior to 1.8.3 are strongly encouraged to update. See this announcement post on our forum.
A JAR file version may be downloaded as well but is only recommended for developers or other advanced users.
Mac Users are encouraged to use the PKG version of the install. Windows users are encouraged to use the MSI.
If you need interactive help, please join our Discord Server. Or visit our wiki for complete walk-throughs of how to use the tool. Our Community page has more links; see the toolbar at the top of the page.
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