Execute specific class/method in jar

Hi!
Is there any way to execute a particular main method of a class inside a jar-file? I have several main-methods that I would like to run, something like this:
java -jar my.jar classA
java -jar my.jar classB
but I find no way of doing it. Is it possible?

I thought so to. It doesn't. It says
"NoClassDefFoundError: "I am assuming the class that isn't found is one of the main classes. Either the class is not in the jar, the class is not correctly installed into the jar, or you did not correctlys specify the class.
For example, if the classes are in package yourpack and are named Main1 and Main2, they must be in the jar as yourpack/Main1 and yourpack/Main2. You must specify them as in
java -classpath path/to/thejar.jar yourpack.Main1

Similar Messages

Specific class methods via reflection?

I need to get the methods of a class, but not the methods that are inherited by the class, but just those implemented in the actual class.
I tried this way:
public class MethodsTest {
    private int prim;
    private String joc;
    public String getJoc() {
        return joc;
    public void setJoc(String joc) {
        this.joc = joc;
    public int getPrim() {
        return prim;
    public void setPrim(int prim) {
        this.prim = prim;
    public static void main(String[] args) {
        // get the methods
        MethodsTest mt = new MethodsTest();
        Class clz = mt.getClass();
        Method[] mtz = clz.getMethods();
        System.out.println(Arrays.toString(mtz));
        // it prints all methods.
}but it prints all methods, from this class and from the superclasses:
[public java.lang.String com.datamedical.testes.xml.MethodsTest.getJoc(),
public void com.datamedical.testes.xml.MethodsTest.setJoc(java.lang.String),
public int com.datamedical.testes.xml.MethodsTest.getPrim(),
public void com.datamedical.testes.xml.MethodsTest.setPrim(int),
public static void com.datamedical.testes.xml.MethodsTest.main(java.lang.String[]),
public native int java.lang.Object.hashCode(),
public final native java.lang.Class java.lang.Object.getClass(),
public final void java.lang.Object.wait(long,int) throws java.lang.InterruptedException,
public final void java.lang.Object.wait() throws java.lang.InterruptedException,
public final native void java.lang.Object.wait(long) throws java.lang.InterruptedException,
public boolean java.lang.Object.equals(java.lang.Object),
public java.lang.String java.lang.Object.toString(),
public final native void java.lang.Object.notify(),
public final native void java.lang.Object.notifyAll()]

http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Class.html#getDeclaredMethods()

How to modify a specific class in jar file ?

I've downloaded a jar file for applet, the jar file works fine... but when I extract a specific class file from the jar file and just recompie it from my IDE (Eclipse) without even making any change and then compress again jar class files including the new modified class file instead of the old one (without any modifications to other classes)... then I get
(NoSuchMethodError ) exception whenever methods of other classes are invoked from within the modified class !!
...The manifist file of the jar file reads the following line
Created-By: 1.4.0_01 (Sun Microsystems Inc.)
I thought it means that jar class files were built using JDK 1.4.0_01 ...I used JDK 1.5.0_01 in my IDE...
I thought JRE incompatiblity was the reason of the problem so I downloaded JRE 1.4.0_01 and used it to build this class file... but i got the same exception..
so what is the main reason of the problem ? ...should I make changes to IDX files accompanying applet jar files ??
If no, then how can I overcome this problem and be able to change and rebuild a specific class from this jar file ?
(I cannot rebuild all classes in jar because there are errors I cannot resolve !!)

Could you please clarify: do you want to run your project or a project from an independent jar?
In the first case just select Run Project from the project context menu or select a class with main method and click Run File in the class context menu.
Regarding the second case:
- I don't think there is such a feature in the IDE (running third party jars is not an IDE function). Could you explain why you need this?

Unable to execute java class.

HI !
I have got a very weird problem .I have wrritten a simple java program Hello world using Weblogic workshop.As required I'm saving this file in the package folder and executing it .I have set the home directories properly .My code is :
package java1;
public class hello
public static void main(String[] args)
System.out.println("Hello World");
After I compile I get the foolowing in the o/p window :
Trying to attach to 3218...
Starting process in C:\bea\myprojects
C:\bea\jdk141_02\bin\javaw.exe -Xdebug -Xnoagent -Djava.compiler=NONE -Xrunjdwp:transport=dt_socket,address=3218,suspend=y,server=y -classpath myprojects.proj1.java1.hello
Usage: javaw [-options] class [args...]
(to execute a class)
or javaw -jar [-options] jarfile [args...]
(to execute a jar file)
where options include:
-client     to select the "client" VM
-server     to select the "server" VM
-hotspot     is a synonym for the "client" VM [deprecated]
The default VM is client.
-cp -classpath <directories and zip/jar files separated by ;>
set search path for application classes and resources
-D<name>=<value>
set a system property
-verbose[:class|gc|jni]
enable verbose output
-version print product version and exit
-showversion print product version and continue
-? -help print this help message
-X print help on non-standard options
-ea[:<packagename>...|:<classname>]
-enableassertions[:<packagename>...|:<classname>]
enable assertions
-da[:<packagename>...|:<classname>]
-disableassertions[:<packagename>...|:<classname>]
disable assertions
-esa | -enablesystemassertions
enable system assertions
-dsa | -disablesystemassertions
disable system assertions
I dont know what to do ? Do I have to set any paths or any thing ? It is not required to set the class path here.
Please Help.
Thanks in advance.

try to compile your programm from command prompt
change dir to hello.java directory
to compile programm type:
javac hello.java
if it will compile successfully run it by typing
java hello
if it will not be helpfull uninstall JDK 1.4 and instal JDK again. I'd recomend JDK 1.5.

Class not found, Jar not executing

Hello,
I created a JAR file and cannot execute it by running java -jar myjarfile.jar. I get no error message and it does not execute.
If I extract the JAR, and run my main class with java packagename.myclass it works fine
If I run javaw myjarfile.jar it tells me it cannot find the main class
My manifest file looks like this:
Manifest-Version: 1.0
Ant-Version: Apache Ant 1.7.0
Created-By: 1.5.0_14-b03 (Sun Microsystems Inc.)
Main-Class: mypackage.Main
This program works fine when unjarred and also from my IDE.

xarfox wrote:
Ok, in that case - is this behavior acceptable:
The first thing I do is:
configFile = reader.read(System.getProperty("user.dir") + "\\CustomConfig.xml");This stores the xml file in a variable of type document (which represents an xml document)
From that point forward I have all the info I need. Can I do this inside a JAR?
Additionally, do you have any feedback on how I can fix what seems to be a classpath issue. What command should I be using to run my JAR file to ensure that it is able to find "mypackagename.Main"
Thank you!If I understand correctly, the file CustomConfig.xml is inside the jar. You do not need user.dir because getClass().getResourceAsStream() will look inside the jar, assuming the object you use was loaded from the jar. If I remember correctly, if your class is in a named package, you need to start the file path string with a / character - ...getResource("/CustomConfig.xml").
Second question: If you correctly specify the main class, then you just need java -jar yourjarfile.jar

How to put native methods in jar file

Hi.I have an executable jar file(test.jar) that makes use of other jar files and native methods. For example, test.jar uses Jnpout32.dll. . test.jar , the other jar files and the native methods are all in the same directory. When I created test.jar I wrote a manifest file which specifies the class path of the other jar files and the native methods as follows and provided it as an option in the jar cfmev command.
Class Path: jdbc.jar Jnpout32reg.dll //content of manifest.txt file that I provided to the jar command
//carriage return I then run the command java -jar test.jar to run the file.
All I am seeing is the following error message
Exception in thread "AWT EventQueue-o
"Java.lang.NoClassDefFoundError.
gnu/io/SerialPortEventListner"
{code}
Any ideas? thanks in advance!
Edited by: Nostalgia on May 22, 2009 8:05 AM

You seem to be confusing Java's classpath with your os's path. The classpath only applies to Java classes. See if this discussion helps:
http://www.inonit.com/cygwin/jni/helloWorld/load.html

Target to execute multiple junit tests from jar file

I have written a custom selenium framework using JUnit and Selenium, problem I am having right now is our team wants to run the tests inside HP Quality Center (I have no idea or any experience with Quality Center) but if I provide a jar file the them they can execute it inside the Quality Center (Reason to run it in Quality Center is for reporting purpose).
Problem is that I have created my framework in away that You can create multiple JUnit base test files for different tests also keep in mind that these classes dont need main method (This is where the problem when it comes to jaring up ). I have introduced following ant target to run all the test cases.
     <target name="test.selenium" depends="jar" description="target to execute all the selenium tests.">
          <junit printsummary="yes">
               <classpath>
                    <path refid="classpath"/>
                    <path refid="application"/>
               </classpath>
               <batchtest fork="yes">
                    <fileset dir="${src.dir}" includes="**/Test*Selenium.java"/>
               </batchtest>
          </junit>
     </target>above ant target runs without any problem, but when you jar it up you need a manifest and main class, is there away I cant introduce some attribute that can execute all my tests without adding main method to each of them.
Here is my ant target for jar
     <target name="jar" depends="compile"
               description="Generates final jar">
          <copy todir="${build.jar}">
               <fileset dir="lib" excludes="**/*.java"/>
          </copy>
          <jar jarfile="${build.jar}/yukonSelenium.jar"
                    basedir="${build.classes}">
               <manifest>
                    <attribute name="Main-Class" value="com.somepackage.selenium.test.TestAuthenticationSelenium"/>
                    <attribute name="Class-Path"
                         value=". /c:/build/jar/log4j-1.2.15.jar /c:/build/jar/junit-4.6.jar /c:/build/jar/selenium-java-client-driver.jar /c:/build/jar/dom4j-1.6.1.jar"/>
               </manifest>
          </jar>
     </target>And this is how the Test Class looks like, I have added main method in this but once i do this after jaring java -jar myJarfile.jar will only execute just the class i have main method init.
public class TestAuthenticationSelenium extends SomePrivateFrameWorkClass {
     private void init() {
          start();
     @Test
     public void testProductNav() {
            //somecode
     @Test
     public void multipleLogin() throws FileNotFoundException, InterruptedException {
                         //Some Code
     public static void main(String[] args) {
          org.junit.runner.JUnitCore.main("com.somepackage.selenium.test.TestAuthenticationSelenium");
}Please let me know if i should put the entire ant build file.
Thanks for any help.
anuradha.uduwage
Edited by: Tilter on Aug 24, 2009 10:05 PM
Edited by: Tilter on Aug 24, 2009 10:06 PM

What i mean is if i have 3 class files in my jar file, and each one of those classes has a main method, how will i be able to execute a class of my choice from that jar file. In manifest files, you specify the main class, but how would i specify multiple classes with main methods, or achieve my objective here.

Java class uses another class in a Jar file (How do I make Java see it)?

I am trying to figure out how do I make Javac see the thinlet.class in the thinlet.jar.
I have developed an XUL xml interface and a java program that calls the interface shown below:
//package thinlet.demo;
import thinlet.*;
public class UI extends Thinlet
{ public UI () throws Exception {add(parse("UI.xml"));}
public static void main(String[] args) throws Exception
{ new FrameLauncher("UI", new UI(), 600, 600); }}
when I do the normal compile, I get an error:
UI.java:4: cannot find symbol
symbol: class Thinlet
public class UI extends Thinlet {
^
UI.java:7: cannot find symbol
symbol : method parse(java.lang.String)
location: class thinlet.demo.UI
add(parse("UI.xml"));
^
UI.java:12: cannot find symbol
symbol : class FrameLauncher
location: class thinlet.demo.UI
new FrameLauncher("UI", new UI(), 600, 600);
^
3 errors
This thinlet class should be in the thinlet.jar that I have added the directory to the path, the directory and jarfile name to the System CLASSPATH and it couldn't see it. So finally I tried putting the thinlet.jar in the same directory to no avail. I've searched the web for some time an cannot find anything that specifically speaks to compiling a program that has parent classes in a Jar.
Any help is definitely appreciated.

This thinlet class should be in the thinlet.jar that I have added the directory to the path, the directory and jarfile name to the System CLASSPATH and it couldn't see it. So finally I tried putting the thinlet.jar in the same directory to no avail. I've searched the web for some time an cannot find anything that specifically speaks to compiling a program that has parent classes in a Jar.
Any help is definitely appreciated.You just still haven't provided the jar in the classpath, or you're not using the right class name. Is the class really named thinlet.Thinlet? Or are you thinking "import thinlet.*" means to import all classes in a jar named thinlet.jar? Because the latter is not true. You need to import classes, not jar file names.

Can't load any classes from infobus.jar (WL 6.0 SP1)

Hi,
I am deploying an .ear file, which has one .war file in it. The war file, has
infobus.jar, inside it under \WEB-INF\lib. Whenever in my servlet code I try to
load a class from infobus.jar, I get the following exception :
About to load class javax.infobus.InfoBusDataConsumer<<<<<<<<<<java.lang.ClassNotFoundException: InfoBusDataConsumer
at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:178)
at weblogic.utils.classloaders.ChangeAwareClassLoader.findClass(ChangeAwareClassLoader.java:45)
at java.lang.ClassLoader.loadClass(ClassLoader.java:297)
at java.lang.ClassLoader.loadClass(ClassLoader.java:253)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:313)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:120)
at XDILoginForm.init(XDILoginForm.java:99)
at weblogic.servlet.internal.ServletStubImpl.createServlet(ServletStubImpl.java:638)
at weblogic.servlet.internal.ServletStubImpl.createInstances(ServletStubImpl.java:581)
at weblogic.servlet.internal.ServletStubImpl.prepareServlet(ServletStubImpl.java:526)
at weblogic.servlet.internal.WebAppServletContext.preloadServlet(WebAppServletContext.java:1078)
at weblogic.servlet.internal.WebAppServletContext.preloadServlets(WebAppServletContext.java:1022)
at weblogic.servlet.internal.HttpServer.loadWARContext(HttpServer.java:499)
at weblogic.servlet.internal.HttpServer.loadWebApp(HttpServer.java:421)
at weblogic.j2ee.WebAppComponent.deploy(WebAppComponent.java:74)
at weblogic.j2ee.Application.deploy(Application.java:175)
at weblogic.j2ee.J2EEService.deployApplication(J2EEService.java:173)
at weblogic.management.mbeans.custom.Application.setLocalDeployed(Application.java:217)
at weblogic.management.mbeans.custom.Application.setDeployed(Application.java:187)
at java.lang.reflect.Method.invoke(Native Method)
at weblogic.management.internal.DynamicMBeanImpl.invokeSetter(DynamicMBeanImpl.java:1136)
at weblogic.management.internal.DynamicMBeanImpl.setAttribute(DynamicMBeanImpl.java:773)
at weblogic.management.internal.DynamicMBeanImpl.setAttribute(DynamicMBeanImpl.java:750)
at weblogic.management.internal.ConfigurationMBeanImpl.setAttribute(ConfigurationMBeanImpl.java:256)
at com.sun.management.jmx.MBeanServerImpl.setAttribute(MBeanServerImpl.java:1356)
at com.sun.management.jmx.MBeanServerImpl.setAttribute(MBeanServerImpl.java:1331)
at weblogic.management.internal.ConfigurationMBeanImpl.updateConfigMBeans(ConfigurationMBeanImpl.java:318)
at weblogic.management.internal.ConfigurationMBeanImpl.setAttribute(ConfigurationMBeanImpl.java:259)
at com.sun.management.jmx.MBeanServerImpl.setAttribute(MBeanServerImpl.java:1356)
at com.sun.management.jmx.MBeanServerImpl.setAttribute(MBeanServerImpl.java:1331)
at weblogic.management.internal.MBeanProxy.setAttribute(MBeanProxy.java:291)
at weblogic.management.internal.MBeanProxy.invoke(MBeanProxy.java:173)
at $Proxy7.setDeployed(Unknown Source)
at weblogic.management.console.pages._panels._mbean._application._jspService(_application.java:303)
at weblogic.servlet.jsp.JspBase.service(JspBase.java:27)
at weblogic.servlet.internal.ServletStubImpl.invokeServlet(ServletStubImpl.java:213)
at weblogic.servlet.internal.WebAppServletContext.invokeServlet(WebAppServletContext.java:1265)
at weblogic.servlet.internal.ServletRequestImpl.execute(ServletRequestImpl.java:1622)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:137)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:120)
But if I put the infobus.jar on system classpath , everything works out fine.
Can somebody tell me, what is going on

Gseel is right: you try to instantiate an EJB with the BDK.
Enterprise Java Beans are totally different from graphical/GUI beans. EJBs are thought for dealing with business logic like accessing a database, ldap directory and so on. They run on a application server (simply speaking - a java enabled webserver) and do some processing to handle user requests. Enterprise Java Beans usually don't interact directly with the user, they only do the work in the background and forward their results, which are then rendered for the user. Typically they are employed for handling web requests (a user with a browser), but they can also be used for awt/swing applications. Though - let me repeat - they don't appear visually on the screen.
The only similarities between those two bean types are the following: they have getter/setter methods for their properties, they implement Serializeable (or a sub-interface like Externalizable, Remote) and they have a default no-argument constructor.
If you want to run your been you need an application server (your bean is pre-packaged for the Bea Weblogic app-server). If you want to do something graphical, you'll need to search for GUI beans.
dani3l

Call(execute) a class in another class

Hi,
please I am a newbie in java and I want call and show the result of algorithm in a method of another class
the algorithm that I use is apriori algorithmhttp://www2.cs.uregina.ca/~dbd/cs831/notes/itemsets/itemset_prog1.html, that algorithm should use two files like arguments:config.txt and transa.txt when I excute this algorithm in line command the algorithm output is file called apriori-output.txt so i want excuteafter show result of this algorithm inside a class called JadeProject and and more specifically in method called setup()
so how can call and execut this algorithm
thanks in advance

Hi gimbal2,
thank you for your reply,
My problem is the following:
my question is how can I execute the apriori algorithm inside the agent code (java class)
I want to build multi agent system using jade(framwork based in java language it is used to build multi agent system) my multi agent system is composed in many agents
those agents are juste java classes
My aim is to execute an algorithm(java class) in agent class
this algorithm is the data mining algorithm apriori http://www2.cs.uregina.ca/~dbd/cs831/notes/itemsets/itemset_prog1.html
the apriori algorithm use two text files :config.txt and transa.txt
i put the algorithm aprioir and the two files in the same directory and i compile the algorithm java class in line command
the output of the execution of algorithm is generating in text file called apriori-output.txt
but I am using netbeans and no line command
my question is how can I execute the apriori algorithm inside the agent code (java class)
thank you in advances

Need Help with command line arguments for a class method

Hey guys,
I'm fairly new to programming in java.
I want to a write a class method that adds up its command line arguments which are numbers. For example, if the input was .... 5 2 3....then the output would be 10.
I have been told to use the Convert to convert a string to a double. I'm ok for writing the class method but I have no idea how to use Convert and why I need it in the method.
Can anybody help please?

Hey guys,
I'm fairly new to programming in java.
I want to a write a class method that adds up its
command line arguments which are numbers. For
example, if the input was .... 5 2 3....then the
output would be 10.Okay. So you would receive the numbers to add as the String[] argument to a main method. The steps are simple:
1) declare a variable for the count
2) for each String in the array:
2.1) extract the value as a double
2.2) add this to the count
3) output the resulting count
I have been told to use the Convert to convert a
string to a double.
I'm ok for writing the class
method but I have no idea how to use ConvertThere is no class Convert in the Java API.
and why
I need it in the method. Do you understand you need to somehow convert each String to a double (step 2.1)? Since Convert is unknown to me, maybe you should just take a look at class Double. It can help you do step 2.1, the rest should be trivial enough.
http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Double.html
Give it a go and feel free to post back with a specific problem you are having, accurately described if you please :-)

Dinamyc class loading and jar files

I'm new to java. I would like to load some plugins in my application (it's going to be packaged as a jar at the end). I managed to find some dinamyc class loading examples but they search for the classes to load in a directory.
This is the code:
    public static void main(String[] args) {
        File pluginDirectory = new File("src/pluginsreloaded/plugins");
        if (!pluginDirectory.exists()) {            // the plugin directory does not exist
            System.out.println("The plugins directory does not exist!");
            return;
        FilenameFilter filter = new FilenameFilter() {
            public boolean accept(File dir, String name) {
                return name.endsWith(".class");
        String[] pluginFiles = pluginDirectory.list(filter);
        for (int i = 0; i < pluginFiles.length; i++) {
            if (pluginFiles.indexOf("$") == -1) {
System.out.println("Loading: " + pluginFiles[i].substring(0, pluginFiles[i].length() - 6));
IPlugin plugin = pm.loadPlugin(pluginFiles[i].substring(0, pluginFiles[i].length() - 6));
System.out.println(plugin.description());
protected static IPlugin loadPlugin(String name) {
        // Query the plugin list for the plugin
        PluginFactory _plugin = (PluginFactory) pluginList.get(name);
        if (_plugin == null) {          // the plugin is not loaded
            try {
                Class.forName("pluginsReloaded.plugins." + name);
                // The plugin makes an entry in the plugin list
                // when loaded
                _plugin = (PluginFactory) pluginList.get(name);
                if (_plugin == null) {
                    return null;
            } catch (ClassNotFoundException e) {
                System.out.println("Plugin " + name + " not found!");
        return _plugin.create();
    }IPlugin is an interface. I am using netbeans 5.0. The error I get is this:
Exception in thread "main" java.lang.NoClassDefFoundError: pluginsReloaded/plugins/plugin1 (wrong name: pluginsreloaded/plugins/plugin1)
        at java.lang.ClassLoader.defineClass1(Native Method)
        at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
        at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
        at java.net.URLClassLoader.defineClass(URLClassLoader.java:260)
        at java.net.URLClassLoader.access$100(URLClassLoader.java:56)
        at java.net.URLClassLoader$1.run(URLClassLoader.java:195)
        at java.security.AccessController.doPrivileged(Native Method)
        at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
        at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:268)
        at java.lang.ClassLoader.loadClass(ClassLoader.java:251)
        at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
        at java.lang.Class.forName0(Native Method)
        at java.lang.Class.forName(Class.java:164)
        at pluginsreloaded.PluginManager.loadPlugin(PluginManager.java:30)
        at pluginsreloaded.Main.main(Main.java:44)
Java Result: 1As far as I can see it can't find the class. My question is how can I load the class/where can I find it?
Thanks.

You can use the java.util.jar.JarFile class to enumerate the contents of a jar. It's not good practice to search for plugins in this way though. A plugin may well involve serveral classes, which don't all have to be internal. Furthermore its wise to avoid any comitment about the mechaism by which class files are to be fetched. You might want to do it remotely, some time, or load them from a database.
What seesms to be the standard approach is to put a list of plugin classes into the jar as a text file.
Plugins for a given purpose usually implement some specified interface, or extend some abstract class to which their objects can be cast once loaded (without this they aren't really much use).
Say your plugins implment org.myorg.WidgetFactory then you put a list of them, one fully qualified name to a line, in a file or jar entry called META-INF/services/org.myorg.WidgetFactory. You framework picks up all such files from the classpath using ClassLoader.getResources() and loads all the classes whose names if finds, hence you can add new sets of plugins just by adding a new jar or class directory to the class path.

How to get a int value from another class method?

Hi,
how can I get a value of another class method variable value.
example,
class elist
        int a;
     ArrayList<Event> eventArray;
     void addEvent(Event e);
     Event getEvent(int index);
     void removeEvent(int index);
     void orderEventByTime();
interface Event
     void Command();
class servo implements Event
     String ip;
     int time = 10;
     void Command();
class servo_2 implements Event
     String ip;
     int time = 20;
     void Command();
[\code]
I want to get the time value in elist variable a;
and want to compare each class time?.

Hi,
1) this foum provides means to format/tag code, no need to manually add -tags
2) by default, classname start with a capital letter, method names with a lower case letter
3) where do you want to get the time value to Elist.a? During addEvent()?
4) what do you want to do with the time value of each event? Sum all values up to make a an overall sum?
5) where do you want to compare the time value(s)?
To put it in one sentence: please be more specific with your description and answer.
Bye.

Is it possible to call a class in a jar file from JNI environment?

Hi
Is it possible to call a class in a jar file from JNI environment?
Thanks in advance.

Could you explain a bit more what you are trying to do? (In other words, your question is vague.)
o If your main program is written in C, you can use JNI to start a JVM, load classes from the jar of your choice, and call constructors and methods of the objects defined in the jar.
o If your main program is java, and has been laoded from a jar, a JNI routine can call back into java to use the constructors and methods of classes defined in the jar(s).

To More Specific Class & Plugin Architecture

Hello there,
I have a plugin architecture and I want to load a particular class on demand, when a user clicks a button etc.
I can do this using 'Get LV Class Default Value.vi' knowing the path of the .lvclass file, and I can then use the 'To More Specific Class' vi to cast it from type LV Object to the specific class I know it to be.
However if I have 30 different classes with this method I would have to have 30 different class constants in a case structure so I can cast to the right one. This works but it means all the classes are loaded into memory when the program is run, even though the user may never want to use most of them, which is a waste of time/memory.
Is there a better way of doing this please?
Thanks,
Martin

I wonder if minute 4:00 in Michael's video will help you. It avoids the constants, as long as all the classes are descendants of a common class:
http://vishots.com/005-visv-labview-class-factory-pattern/

Execute specific class/method in jar

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