View source for Installation and Setup for using Java in Mathematica

=How to set up a system for using Java in Mathematica=
In this project, we will be mainly using Commands in Mathematica to access Java programs that we write.  Here is how to set up the system:


==How to install ''Mathematica'','' J/Link'', and ''Java''==
*Install ''Mathematica'' following the [http://documents.wolfram.com/mathematica/GettingStarted/SettingUp/InstallingMathematica.html official instructions]. 

*''Jlink'' is already completely installed in ''Mathematica 4.2'' and later. If you are using earlier versions of ''Mathematica'', you can install ''JLink'' following the  [http://www.wolfram.com/solutions/mathlink/jlink/Installation.html official instructions]. 

*Download ''JRE 5.0 Update 6'' (latest as of June 2006) the latest version from [http://java.sun.com/j2se/1.5.0/download.js Sun] and install it following the official [http://java.sun.com/j2se/1.5.0/install.html official instructions].

==How to start using ''Jlink'' in a ''Mathematica'' notebook==
*Write the Java source code (''.java'' files) and compile it using the command
 javac file.java
Place the compiled files (''.class'' files) in the directory you want. (I have not tried to make .jar files yet so I will not write about it here)

*For detailed documentation on ''JLink'', please consult the ''Jlink'' manual in the ''Mathematica'' Help Browser.  The following are extracted from there.

*Open a ''Mathematica'' notebook, install ''JLink'' by (writing and executing): 
 Needs["JLink`"] 

*Install ''Java'' by:
 InstallJava[] 
or to use a specific java runtime if you have more than one installed on your computer:
 InstallJava[commandLine->"/wherever/java/is"] in Linux
 InstallJava[CommandLine -> "d:\\\\path\\to\\javaw.exe"] in Windows 

*Add the directory which contains the compiled java (.class) files to the class path, ie, where Java will look for class files, by 
 AddToClassPath["wherever/my/class/files/are"] in Linux
 AddToClassPath["c:\\my\\java\\dir"] in Windows

*Create New Java Objects by
 JavaNew["classname1",constructorArg1,constructorArg2...]


*Access the non-static methods and variables of any object the same way you would in Java except replace "'''.'''" (''java'') by "'''@'''" (''Mathematica'') and "'''()'''" (''Java'') by "'''[]'''" (''Mathematica''). Access static methods or variables by replacing "'''.'''" in ''Java'' by "'''`'''" in ''Mathematica''. (I haven't used the static methods yet so I am not entirely sure.)