How to run calcoo.jar


This page is meant for people who do not know how to run software distributed as a .jar file, like the current version of Calcoo. If you do know how to run a .jar, you are unlikely to find anything new here. If you have downloaded (or are going to download) calcoo.jar, and do not know how you could run it, please keep on reading.

Why Java

Version 2 of Calcoo is written in Java, which is a much more modern computer language than C used for version 1 of Calcoo. Java gives developers the huge benefit of their software being able to run on any platform that Java runtime has been ported to by Sun/Oracle. However, this means that a user who wants to run Calcoo needs to have Java runtime installed.

Is Java already there?

To run Calcoo, you need a recent version of Java, at least Java SE 7 (also known as "Version 7" or "1.7"). You may already have Java installed on your machine. To check it, open a terminal window aka "command prompt" (in Windows: Start → All Programs → Accessories → Command Prompt, in Mac OS: Applications → Utilities → Terminal) and type (or copy) "java -version" (without quotes) there and hit "Enter". If you get something like "java version "1.7.0_13" etc", you have what you need to run Calcoo. If the system cannot recognize the command, or if the version shows as 1.6 or earlier, you need to install the latest Java. On Mac OS, when you run "java -version", the system may tell you that Java is not installed, and offer you to install it. Alternatively, on Mac OS you can just double-click the .jar file, and if Java is not installed, the system will invite you to install it. Follow that suggestion, and get Java installed. While it is necessary, it may not get you version 1.7 of Java. Mac OS is somewhat special, because of their recent transition from Apple-supplied Java 1.6 to Oracle-supplied Java 1.7. As a result, running "java -version" may report version 1.6 even if you have version 1.7 installed. A more reliable way is to check the System Preferences, as outlined here, which also contains other information for Mac users.

How to install Java SE 7

Get it here, or, if you want more manual control, here. Mac users will find even more details on this page. Note that you do not need to enable Java in your browser to run Calcoo. Also, it is sufficient to install JRE, though installing JDK (which includes JRE) is also Ok. If your platform is not listed there (for example, FreeBSD, or Mac OS X 10.6 "Snow Leopard" or earlier), you are on your own. You may want to use OpenJDK, for example, if it is available for your platform. After you are done installing, you can verify it by running "java -version" from the command prompt. Note: for Mac OS, if you just installed JRE (not JDK), it will still report version 1.6, even though 1.7 has been installed. Run "/Library/Internet\ Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/bin/java -version", and if that reports 1.7, you are good.

How to run calcoo.jar

Once you have a suitable version of Java installed, you can run Calcoo by running command "java -jar calcoo.jar" in a terminal window aka "command prompt" from the folder/directory where you saved it. In Windows and Mac OS, you can also run it by double-clicking on calcoo.jar.