How to catch return value from paramter we pass from CL/CLE through Java in Qshell

[wahyu_komara]

Hello Java & AS/400 Expert..

I make small application from CL called java with Qshell (QSH).
java will accept 2 paramter which is passed from CL, and calculate it.
example : CL passed 2 parameter , e.g &PARM1 ='2' and &PARM2='0' to Java , then java will process with formula : strResult=&PARM1 *100 ,
my question , How CL catch strResult (java variable) and assign it value to &PARM2
bellow I include snippet code both CL ana java code

CL code (CALCULATE.CLP) :

PGM                                                                     
             DCL        VAR(&PARM1) TYPE(*CHAR) LEN(1) VALUE('2')       
             DCL        VAR(&PARM2) TYPE(*CHAR) LEN(5) VALUE('0')       
             DCL        VAR(&JAVA) TYPE(*CHAR) LEN(255)                 
                                                                        
             CHGVAR     VAR(&JAVA) VALUE('java example.Calculate ' +    
                          *CAT &PARM1 *CAT ' ' *CAT &PARM2)           
                                                                        
                                                                        
             CHGCURDIR  DIR('/home/sh30')                               
             CHKOBJ     OBJ(QTEMP/DIRLIST) OBJTYPE(*FILE)               
             MONMSG     MSGID(CPF0000) EXEC(DO)                         
                                                                        
             CRTPF QTEMP/DIRLIST RCDLEN(5000)                           
             ENDDO                                                      
                                                                        
             OVRDBF FILE(STDOUT) TOFILE(QTEMP/DIRLIST)                  
             QSH        CMD(&JAVA)                                      
          DLTOVR FILE(STDOUT)   
ENDPGM

java Code (Calculate.java)

package example;

/**
 * File name   : Calculate.java
 * @author wahyu komara
 *Created Date : Nov 26, 2010  
 */
public class Calculate {
	private int result;
	public Calculate(String[] strArgs){
		result=Integer.parseInt(strArgs[0]) *100;
	}
public int getResult() {
		return result;
	}
	public void setResult(int result) {
		this.result = result;
	}
public static void main(String args[]){
	Calculate calculate=new Calculate(args);
	args[1]=""+calculate.getResult();
	System.out.println(args[1]);

}
}

when I debug CL, the value of &PARM2 doesn't change yet....still remain '0 '

any respond, and comment is highly appreciated


Regards,


Wahyu Komara

[BenThurley]

Re: How to catch return value from paramter we pass from CL/CLE through Java in Qshel

The parameters to a Java method are always pass by value. If the parameter is an object then the value is the object reference which means you have the same object referenced twice, or more. In most cases if you pass an object in to a method and change it then the calling method will also see the change, since they both have references to the same object. In the case of the main method it is different because the caller of the main method is outside the scope of the program.

Running the program from QShell like this could work if your program was self contained. If for instance you gave it a couple of strings and it then generated a PDF or XLS and writes it to a particular IFS location then that could work. If on the other hand you want to call the code like you would a service program in RPG then you need a different tact.

You might like to have a read of these articles.

http://www.itjungle.com/mpo/mpo013102-story02.html

http://www.itjungle.com/mpo/mpo042403-story04.html

[wahyu_komara]

Re: How to catch return value from paramter we pass from CL/CLE through Java in Qshel

Yes Ben, My program is intended to make PDF File from AS/400 Report Spool, after java convert the spool into PDF then sent to particular email.
when the report creation is processed I need to get report PDF filename (available from java variable name) in order to display it in Screen DSPF,
so user notes generated report name and suited with email delivered.

I have read the link you gave, but I still confuse , may be I need more practice and explore
Ok, thank you for your help..

[BenThurley]

Re: How to catch return value from paramter we pass from CL/CLE through Java in Qshel

The links show you how to hook into Java code from RPG without using the main method. You could create a class that has methods something like this:

public class PDFGen
{
public PDFGen()
{
// Use the constructor from your RPG program to create a PDFGen object
}

public void setContent(String content)
{
// You can call methods to pass in content to your created PDFGen object
}

public String getIFSLocation()
{
// And you can retrieve information by calling methods too!
}
}