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Help! I had no luck posting this on the RPG400 mailing list, so here goes: I've been tinkering (fumbling blindly would be more accurate) around with calling Java methods from RPG to generate / update Excel spreadsheets (using the classes provided by the Jakarta Poi APIs - http://jakarta.apache.org/poi/hssf/index.html). I did a search of the news group and it seems some people have been using this stuff with a greater degree of success than me, but couldn't find anything that would solve my problem directly. I've managed to write a couple of proof-of-concept programs (hence the shoddy code below) that will run in batch and interactive mode to create spreadsheets from scratch and write them out to the IFS (which are then emailed out to users). Creating xls from scratch seems to work just fine. I'm having a problem when I try to open up an existing spreadsheet for updating inside a batch job ( I only need to change the contents of particular cells & re-save the file). I can call my program interactively with no problems at all and get an updated spreadsheet at the end of it that is persisted to the IFS, but if I try to run it is a batch job with a SBMJOB I get the error message: ***** Message . . . . : Java exception received when calling Java method. Cause . . . . . : RPG procedure JAVAXLS8 in program DHWORKLIB/JAVAXLS8 received Java exception "java.io.IOException:" when calling method "<init>" with signature "(Ljava.io.InputStream;)V" in class "org.apache.poi.poifs.filesystem.POIFSFileSystem". Recovery . . . : Contact the person responsible for program maintenance to determine the cause of the problem. Technical description . . . . . . . . : If the exception indicates that the Java class was not found, ensure the class for the method is in the class path. If the exception indicates that the Java method was not found, check the method name and signature. If the signature is not correct, change the RPG prototype for the method, or change the Java method, so that the return type and parameter types match. You can determine the signatures for all the methods in class XYZ using command QSH CMD('javap -s XYZ'). ***** Not much help to the uninitiated .... Here's some code snippets / prototypes from the program in question: 0008.00 D jInStream S O CLASS(*JAVA: 0009.00 D 'java.io.InputStream') 0020.00 * // openHandle = openFile( fileName) 0021.00 D openFile PR O EXTPROC(*JAVA: 0022.00 D 'java.io.FileInputStream': 0023.00 D *CONSTRUCTOR) 0024.00 D fileName O CLASS(*JAVA: 0025.00 D 'java.lang.String') 0021.00 * // createPOIFSFileSystemForInput( java.io.InputStrean) 0022.00 * // Creates a POI FileSystem object from a java input stream, 0023.00 * // required for reading exising xls files. 0024.00 D createPOIFSFileSystemForInput... 0025.00 D PR O EXTPROC(*JAVA: 0026.00 D 'org.apache.poi.poifs.filesystem- 0027.00 D .POIFSFileSystem': 0028.00 D *CONSTRUCTOR) 0032.00 D inputStream O CLASS(*JAVA: 0033.00 D 'java.io.InputStream') ---> Main code begins here: 0015.00 D Recursive S N 0016.00 D JNIEnv_P S * 0017.00 D capacity S 10I 0 INZ(10000) 0018.00 D rowPos S 5 0 0019.00 D rowPosSave S 5 0 0020.00 D cellPos S 5 0 0021.00 D IFSFile S 1024 VARYING 0022.00 D INZ('/tmp/tstSales.xls') 0023.00 D wrkChar S 1024 VARYING 0024.00 D wrkDouble S LIKE( jDouble) ... 0032.00 *--------------------------------------------------------------------* 0033.00 * Object variables * 0034.00 *--------------------------------------------------------------------* 0035.00 D wrkString S LIKE( jString) 0036.00 D trimmedString S LIKE( jString) 0037.00 D filename S LIKE( jString) 0038.00 D inFile S LIKE( jInStream) 0039.00 D outFile S LIKE( jOutStream) 0040.00 D fs S LIKE( poiFileSystem) 0041.00 D wb S LIKE( poiWorkbook) 0042.00 D sheet1 S LIKE( poiSheet) 0043.00 D row S LIKE( poiRow) ... 0104.00 Monitor; 0105.00 0106.00 // Set the classpath 0107.00 cmdString = 'ADDENVVAR ENVVAR(CLASSPATH) VALUE(' + x'7D' + 0108.00 cCLASSPATH + x'7D' + ') REPLACE(*YES)'; 0109.00 RunCmd( %TRIMR( cmdString) ); 0110.00 0111.00 0112.00 // Get pointer to JNI Environment 0113.00 JNIEnv_P = getJNIEnv('-Djava.version=1.3;'); 0114.00 If JNIEnv_P = *NULL; 0115.00 *INLR = *ON; 0118.00 0119.00 // Create a new local reference frame so we can clear all the 0120.00 // java objects in one go 0121.00 0122.00 beginObjGroup( JNIEnv_P: capacity); 0123.00 0124.00 // Open the file 0125.00 wrkString = createString( %trim(IFSFile)); 0126.00 // Trim filename (50A). 0127.00 filename = trimString( wrkString); 0128.00 // Create FileInputStream. 0129.00 inFile = openFile( filename); 0130.00 fsBytes = fsBytesAvail( inFile); 0131.00 // Load the file into the POI filesystem 0132.00 fs = createPOIFSFileSystemForInput( inFile); The error here at statement 0132.00. A batch job doesn't seem to have any problems coping with calling other Java methods, including those within the poi.jar (though I haven't tested exhaustively to find any others that don't work). I've tried setting the CLASSPATH manually and using CPYENVVAR(*YES) when doing the SBMJOB, plus I've tried setting the CLASSPATH inline (as I've left the code here) and it makes no difference 0133.00 // Close the input stream (no longer needed) 0134.00 fsClose( inFile); 0135.00 0136.00 // Load the workbook 0137.00 wb = openWorkbook( fs); 0138.00 0139.00 // Retrieve the sheet 0140.00 sheet1 = getSheetAt( wb: 0); 0141.00 // Retreive the Sales row 0142.00 row = getRow( sheet1: 6); 0143.00 0144.00 // Change sales for Q1 + 500 0145.00 cell = getCell( row: 1); 0146.00 wrkDouble = getNumericCellValue( cell) + %Float( 500); 0147.00 setCellValue_double( cell: wrkDouble); ..... 0166.00 0167.00 // Output workbook to file 0168.00 outFile = createFile( filename); 0169.00 writeWorkbook( wb: outFile); 0170.00 0171.00 // Exit on error 0172.00 On-Error; 0173.00 Exsr *PSSR; 0174.00 Return; 0175.00 EndMon; ... 0179.00 Exsr Cleanup; 0180.00 Return; 0181.00 0182.00 /End-Free 0186.00 // *********************************************************** 0187.00 Begsr *PSSR; 0188.00 // *********************************************************** 0189.00 If Not Recursive; 0190.00 Recursive = *ON; 0191.00 Dump; 0192.00 Exsr CleanUp; 0193.00 EndIf; 0194.00 0195.00 Return; 0196.00 0197.00 Endsr; 0198.00 0199.00 // *********************************************************** 0200.00 Begsr Cleanup; 0201.00 // *********************************************************** 0202.00 0203.00 *INLR = *ON; 0204.00 // Free up all Java objects still in use 0205.00 If JNIEnv_P <> *NULL; 0206.00 CallP(e) endObjGroup( JNIEnv_P); 0207.00 EndIf; 0208.00 0209.00 Endsr; 0210.00 0211.00 /End-Free Is there some issue with using a FileInputStream in a batch job or something?? Are there any behavioural differences between running Java in batch and interactively? Or am I just trying to do something that can't be done?? I'm afraid I don't have any Java coding experience at all, just what I've picked out from the V5R2 RPG manual and cobling bits together written by others & would welcome any input at all.. Perhaps I shouldn't be mucking around with this stuff, but you can't blame a guy for trying, eh? I'm on V5R2 of the O/S and using JDK 1.3 if that helps any ? Sorry if this isn't enough info to be going on yet, I just wanted to get my problem "out there" as it's giving me a real headache. Many thanks, David COMPUTACENTER (UK) LTD The contents of this e-mail are intended for the named addressee only. It contains information which may be confidential and which may also be privileged. Unless you are the named addressee (or authorised to receive for the addressee) you may not copy or use it, or disclose it to anyone else. 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