[REBOL] Re: Execute rebol from java
From: nitsch-lists:netcologne at: 3-Jan-2002 18:39
RE: [REBOL] Execute rebol from java
Hi Anton
[arolls--idatam--com--au] wrote:
> Does anyone have any java code to execute a rebol script?
>
> I am having serious withdrawal symptoms today.
> I am forced to use java at work here, and I just came across
> a problem that would have been short, elegant and simple in
> rebol, and almost downright impossible in java (it seems).
>
> I was advised by a more experienced programmer here on
> all the benefits of adding three more classes, when all I
> wanted to do was navigate a simple array/block with a known
> structure and get some strings out.
> (Gnashing of teeth.)
>
> Sorry, I will try to deal with it.
>
> I am going to go looking for a nice parser for java (if there is
> one).
>
reviseted java a bit.
javacc, coco are compiler-compilers, similar to parse.
also there are regular-expressions somewhere near
the jpython (and inbuild in 1.4 or that?).
to use rebol, below is some playing which starts a rebol-script
and fills its output in a vector of lines.
but '\n' as line-delemiter is hardcoded,
forgot the name for the second windows-char..
hope it helps a bit.
> Anton.
-Volker
> --
[
REBOL [title: {do me to build files..}]
make-dir/deep %callrebol-project/volker/callrebol/
WRITE %callrebol-project/callreboldemo.r
{rebol[title: file: %callreboldemo.r
]
inform layout[
button "send"[hide-popup print ta/text]
ta: area "Hello Java!"
]
}
WRITE %callrebol-project/CallRebolDemo.java
{
import volker.callrebol.RebolConnection;
import java.io.IOException;
/**
* Demonstrate use of package volker.callrebol.
*
* @author volker
* @version 0.1
*/
public class CallRebolDemo
{
// instance variables
static RebolConnection rebolConnection;
/**
* Constructor for objects of class Demo
*/
public CallRebolDemo()
{
// initialise instance variables
}
/**
* the Demo starts here
*
* @param args command line
*/
public static void main(String[] args) throws IOException
{
// put your code here
rebolConnection = new RebolConnection();
/*my ide start in the ".."-directory,
so "callrebol-project" points ot the root-package
with volker.callrebol in it. ugh. configuring around..*/
rebolConnection.scriptAndArguments
="callrebol-project/callreboldemo.r";
rebolConnection.runRebol();
rebolConnection.readAll();
System.out.println(rebolConnection.output.toString());
System.exit(0);
}
}
}
WRITE %callrebol-project/volker/callrebol/RebolConnection.java
{package volker.callrebol;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Vector;
/**
* Call a rebol-job, return console-output.
*
* @author Volker
* @version 0.1
*/
public class RebolConnection
{
//parameter variables
/**set script and arguments for command-line*/
public String scriptAndArguments;
/**here is the script-output, parsed into lines*/
public final Vector output=new Vector();
/**change to point to your rebol*/
public String executable="/usr/local/bin/rebol";
// instance variables
Process rebolProcess;
Runtime runtime=Runtime.getRuntime();
InputStream inputStream;
StringBuffer stringBuffer=new StringBuffer();
/**
* Constructor for objects of class RebolConnection
*/
public RebolConnection()
{
}
/**
* Start rebol based on args in public variables.
*
**/
public void runRebol() throws IOException
{
rebolProcess = runtime.exec(
new String[]{executable,scriptAndArguments});
inputStream = rebolProcess.getInputStream();
}
/**
* parse the input into lines and fill them in this.output.
* can run in another thread.
* attention, lines-delemiter is coded platform-dependent,
* and needed as last char in file.
*
* @param input an input stream
**/
public void readAll()
throws IOException
{
InputStream input=this.inputStream;
int got;
while(-1 != (got=input.read())){
if('\n'==(char)got){
String s = stringBuffer.toString();
stringBuffer.setLength(0);
output.add(s);
}
else{stringBuffer.append((char)got);}
}
}
}
}
]
