QProcess does not start a java application

Question

I made a java program to finish signing an xml since I can't get Signature value by c ++, running by cmd works fine, but using QProcess I get the following error

    QProcess processAssinar;
    processAssinar.start("java -jar " + qApp->applicationDirPath() + "/nfsigner.jar " + pathCertificado + " " + senhaCertificado + " " + xmlFile.fileName());
    processAssinar.waitForFinished(10000);

    qDebug() << processAssinar.arguments();

    if(processAssinar.exitCode() != 0){
        QMessageBox::critical(nullptr, "NF", "Falha ao assinar a nota fiscal");
        qCritical() << processAssinar.readAllStandardError();
        return;
    }

Error:

"java.lang.UnsupportedClassVersionError: com/ivesti/nfsigner/NFSigner : Unsupported major.minor version 52.0\r\n\tat java.lang.ClassLoader.defineClass1(Native Method)\r\n\tat java.lang.ClassLoader.defineClass(Unknown Source)\r\n\tat java.security.SecureClassLoader.defineClass(Unknown Source)\r\n\tat java.net.URLClassLoader.defineClass(Unknown Source)\r\n\tat java.net.URLClassLoader.access$100(Unknown Source)\r\n\tat java.net.URLClassLoader$1.run(Unknown Source)\r\n\tat java.net.URLClassLoader$1.run(Unknown Source)\r\n\tat java.security.AccessController.doPrivileged(Native Method)\r\n\tat java.net.URLClassLoader.findClass(Unknown Source)\r\n\tat java.lang.ClassLoader.loadClass(Unknown Source)\r\n\tat sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)\r\n\tat java.lang.ClassLoader.loadClass(Unknown Source)\r\n\tat sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)\r\nException in thread \"main\" "

Does this help? https://stackoverflow.com/questions/10382929/how-to-fix-java-lang-unsupportedclassversionerror-unsupported-major-minor-versi I assume the wrong JVM is being launched due to paths. — ChrisMM, Nov 04 '19 at 13:55
@ChrisMM But why does it work in cmd? is the same java installed, should work in both or not work in either — Samuel Ives, Nov 05 '19 at 11:50
Qt might have a different path setup, or cmd does. In cmd type in `where java` and do the same from a Qt application. Do they return the same? — ChrisMM, Nov 05 '19 at 11:52

score 0 · Answer 1 · answered Nov 04 '19 at 15:02

0

Probably due to the arguments format. Try this:

QString l_jar_path = qApp->applicationDirPath() + "/nfsigner.jar " + pathCertificado + " " + senhaCertificado + " " + xmlFile.fileName();

QStringList l_args;
l_args << "-jar" << l_jar_path;

QProcess l_proc;
l_proc.start("java", l_args);

answered Nov 04 '19 at 15:02

JuanDeLosMuertos

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I think you should go the full way and pass every segment of l_jar_path as single strings to l_args, to avoid any quoting issues. – Frank Osterfeld Nov 04 '19 at 17:21

QProcess does not start a java application

1 Answers1