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diff --git a/README b/README new file mode 100644 index 0000000000..ae23b4bf32 --- /dev/null +++ b/README @@ -0,0 +1,77 @@ +Copyright 1998, O'Reilly & Associates, Inc. + +This package may be copied under the same terms as Perl itself. + +Disclaimers +----------- +This is a work in progress, and relies on bleeding-edge technology +from the network. Don't expect not to be surprised occasionally. + +Requirements +------------ +Perl 5.004 (or later) must be compiled and installed as a shared library +(libperl.so). I had to use the system's malloc. We've tested +it most heavily with 5.004_04. + +You need JDK 1.1. On Solaris 1.1.1 works. On Linux you need 1.1.3 with +the patches from + + ftp://ftp.blackdown.org/pub/Linux/JDK/1.1.3/updates/libjava-1.1.3v2-1.tar.gz + +The get_jdk directory contains a script that will download JDK (but not +the patch file above) off of the net for you. (This presumes you've +already installed the modules mentioned in ../README.) + +What the heck is JPL? +--------------------- +JPL is a hybrid (to use the polite term) language. It's basically Java +in which the methods can optionally be implemented by Perl code. A +preprocessor called "JPL::Compile" looks at your .jpl file and spits +out the appropriate .java, .c, .h, .pl, and .so files to accomplish the +desired task. Hopefully a lot of those files can go away in the future +as jpl mutates into a Perl-to-Java compiler. The long-term goal is for +jpl to be able to take a pure Perl file and spit out a java .class +file. This initial version of JPL is an attempt to begin to mesh the +semantics of Java and Perl. Some people may find it useful in its +current form, but you should know right up front that we've still got a +ways to go with it. A journey of a thousand miles continues with the +second step... + +JPL Syntax +---------- +JPL syntax is trivial, given that you know Java and Perl. Pretend like +you're writing a native Java method, but say "perl" instead of +"native", and then instead of omitting the body of the method, put your +Perl code in double curlies. (See Sample.jpl for an example.) + +Calling back from Perl to Java is done through the JNI (Java Native +Interface). No weird transmogrifications are done by the preprocessor +to your Perl code--it's all normal Perl. The preprocessor just wraps +it up into funny subroutines you don't see unless you peek at the .pl +file it generates. + +Installation +------------ +Run "install-jpl". You have to tell it whether you want to use the +current directory for JPL_HOME or some other directory. Everything +else should take care of itself, except that after install-jpl +write the setvars program, you are responsible to invoke it properly +before any JPL applications can be compiled under the current shell. + + sh: eval `setvars -sh` + csh: eval `setvars -csh` + perl: eval `setvars -perl`; + +More Info +--------- + +You can look at the Sample and Test directories, as well as the ../eg +directory for examples. + +Perhaps the most important bit of advice we can give you is to watch + + http://perl.oreilly.com + +for further information on how to get further information. + +Have the appropriate amount of fun. |