I have a C++ application that uses JNI to create a Java virtual machine. I have the latest version of Java installed - JDK 8-144. If I run "java -version" it comes up and tells me that Java Hotspot 8 is the JVM. I have JAVA_HOME defined in the .profile file, and it works -- JAVA_HOME points to the JDK8-144 folder.
My application is including jni.h from the latest JDK. Our code creates a JVM with the JNI_VERSION_1_8 version flag. On Windows, this compiles and works perfectly.
The problem is that when we compile this code on the Mac, and use the JVM Framework for linking, we end up with an executable that, when run, says that there's "No Java Runtime present" and a dialog comes up that says we need to install the Version 6 JVM. This happens if we run the application from either the Bash terminal or from XCode.
I've researched this and there are other people who have had this identical issue. Everyone seems to suggest that JAVA_HOME needs to be pointing to the correct place, and mine is. Again, java -version works correctly. The whole thing is quite puzzling.
Does anyone know the right way to solve this? I've tried two different Macs with identical results. They are both running the latest version of macOS Sierra.
Thanks!
Dan
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so, I got a new external monitor for my iMac, and was downloading the latest Java -- java18 -- from java 8. I hadn't used the machine for years, but since getting my new monitor a couple weeks ago, I'm happy to know that I can still use it. I had written it off after the backlight went out, but lo and behold, the machine stills works fine.
Anyway, I downloaded Java 18 from the oracle website, installed it with no problem, but when I go the terminal app and enter
java -version it still says java 1.8 (java 8). I looked in the java folder in the library directory, and sure enough the java 18 folder is there, but for some reason it won't or doesn't 'see' it as the current/default java version.
Anyone out there have any help to give? I'm not sure what terminal commands to use to make this the default version. maybe because it's so far from the version that was on there. Can anyone help me out? The machine is a 2010 iMac 11,6 running El Capitan, and I want to use it while it lasts, as I gradually switch over to Linux.
The machine still works great, and the latest version that was on it before this download was java 8. I'm not at the machine right now, so i'll have to look at this over the next few days.
You need to add in ~/.profile file (create it, if doesn't exist), the setting of JAVA_HOME environment variable, pointing to your Java18 installation directory:
JAVA_HOME=/Path/to/Java18
export JAVA_HOME;
source: http://www.sajeconsultants.com/how-to-set-java_home-on-mac-os-x/
In case of failure, try to do the same but in the files:
~/.base_profile
~/.zshrc
source: https://www.developerlibs.com/2022/06/java-environment-path-setup-windows-linux-Mac.html
I've been working with Java for a bit now and the JDK/JRE version has given me quite a bit of trouble lately. I am developing using the Intellij IDEA IDE and it of course uses the latest version of the JDK, 14. However when I attempt to execute software compiled with JDK 14 outside the IDE, I get an error that the JRE isn't new enough to run this software. So I updated Java on my computer and another machine and attempt to run again without any success. After some digging, I tweaked my machine to use the JRE included in the JDK 14 which is compatible.
However it is kind of odd that I had to do that, one would think that the latest version of java should of been enough to run applications made with the latest version of the JDK (14). Right now Java is version 8 build 251 and says there is no newer update available. If JDK 14 is out for a while now, why would they not update the version of Java they ship?
The problem is partially solved, as only the machine I am using for development is capable of executing the created applications. Other people I've sent them to have been unable to run them, despite having the latest version of java. Also it is a pain to get the latest JDK, especially when having limited experience on how to get rid of old versions, change path point to the latest version, get the right package (open/oracle JDK) and do that for windows and several distrubutions of linux. What is going on? Did I get Java from the wrong place and everyone else as well? Why are oracle doing this and why are there no java updates since clearly there exists a newer version?
Starting with Java-11, separate JRE does not exist anymore. In other words, if you are using Java-11 or above, you should care about JDK only.
You should uninstall JRE-8 from your machine and make sure your JDK-14 bin folder in the PATH variable. Some application even requires JAVA_HOME to work and therefore you should make sure that your system has an environment variable called JAVA_HOME and its value set to the root folder of JDK-14 (i.e. one level above your JDK bin).
Q: What should my clients do to run my application compiled on JDK-14?
Ans: Your clients must install JDK-14. Also, check this thread for some alternatives.
You're confusing how IntelliJ or JDK are used on the OS. IntelliJ, now, often comes with its JDK binaries (but even this can be configured, IntelliJ can be configured to use any JDK/JRE build you'll provide to it); however, if you run your Java application out of IntelliJ, most likely you're using Java installed locally on your OS, which might be referenced via your JAVA_HOME environment variable.
I'd suggest to:
Check java -version in your shell (and hence you'll see what JVM instance your OS spins up when you run a Java application);
Check where java (on Windows, or which - on Linux) in your shell, to see all the Java binaries available on your OS.
Try to uninstall Java SE Development Kit and Java JRE(if you have both in your machine) and reinstall both again, JDK and JRE both, I am sharing my google drive link where you can find the latest version of both JDK and JRE and when you are done installing, add there bin folder path in the Environment Variables of your machine.
This is a followup to this question.
MacOS X has the java command under /usr/bin. If one installs the JRE from Oracle, it doesn't work - claims there's no Java runtime, and offers to download and install Apple's runtime. But if you first run
export JAVA_HOME=/Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home
then java works as expected. That's where Oracle JRE installs itself.
Now I'd like to use the Oracle Java VM in-process, and I can't - the "You need Java runtime" error message keeps popping up, even with JAVA_HOME being set.
Linking against the JavaVM framework causes the message on app startup, even before main().
Trying to dynamically load /Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/lib/server/libjvm.dylib and invoke JNI_CreateJavaVM causes the same message during the method call.
EDIT: the java command does it somehow, after all. I've poked around with a debugger, it does invoke JNI_CreateJavaVM at some point. I've even mimicked the arguments (there's one extra one, -Dsun.java.launcher=SUN_STANDARD), it didn't make any difference.
Found the answer here.
Instead of loading libjvm.dylib, one needs to load /Library/Internet Plug-Ins/JavaAppletPlugin.plugin/Contents/Home/lib/jli/libjli.dylib. It exports JNI_CreateJavaVM, too. Call that one, and it'll work as expected.
Works even with JAVA_HOME not being set.
Future warning: Oracle says that since Java 1.9, the browser plugin technology will no longer be supported. With that in mind, Oracle JRE's home in version 1.9 might not be under Internet Plug-Ins anymore.
so I have this project in java that uses a jni .dll i wrote (which i've aptly named jniusb) that gives access to usb-hid devices. i've been using it for several months now without any notable issues until yesterday when i tried to launch my program from the jar instead of directly from netbeans. after a little debugging i characterized my issue as follows:
clicking on the jar icon starts my program without loading the dll. displaying the error messages in my gui revealed "no jniusb in java.library.path" even though i copied my dll to the java binaries folder (which always seemed to work in the past).
i tweaked the code to find the current directory and use "System.load" (with the dll copied to the same folder as my jar) instead of "System.loadLibrary". this approach threw the error "C:\Users\bpaik\Documents\NetBeansProjects\JniUsb\dist\jniusb.dll: Can't load AMD 64-bit .dll on a IA 32-bit platform". this made me scratch my head since i am most definitely working on an AMD 64-bit platform and running out of netbeans works with the same dll...
running the jar from the command prompt (with either java.exe or javaw.exe) loads the dll just fine. i thought that maybe this meant that i was having admin privileges issues so i tested the theory by going to the java executable and granting admin privileges, but this did not change anything. (and i'm also pretty sure i've used load/loadlibrary before without admin...)
i am no java expert so i've pretty much exhausted my debugging abilities and am now hoping that someone with a little more experience than i will recognize the issue i've described, thanks.
UPDATE: so i've fixed the problem but I still have no idea what is going on. i did a x86 build of my .dll and threw it into the folder with my jar and everything loaded/worked just fine. so i guess somehow (even though i set the default program for my jar to be the x64 JVM) the jar i built with the x64 library in Netbeans is running in a 32-bit JVM. to sum things up:
my jar is built with the x64 library in netbeans and runs fine with the x64 dll when launched from the command prompt.
when launching the jar from the icon (with default program set to x64 java) my program and JVM somehow switch to a 32-bit JVM and work fine when i use the 32-bit version of my dll.
trying to explicitly run my jar with the 32-bit java doesn't work at all. my gui doesn't display and the command prompt briefly opens/closes...
Problem 2 is certainly caused by you running a 32-bit JVM. Netbeans presumably runs a 64-bit JVM. You'll need to use something like Launch4j to get the right JVM loaded (or include both a 32-bit and 64-bit version of your DLL).
From the command line, try -d32 and -d64 to test that theory out.
Do you have multiple versions of Java installed on your Machine? It appears that when you run the jar by itself, your machine is creating a 32-bit VM for it. Open an command prompt and type java -version to check which version of Java is being used.
I am having a runtime error ONLY when I test my Java program on a mac computer. It tests perfectly fine on various Windows operating systems. This is the error message I get on a Mac computer...
Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: javax/swing/GroupLayout$Group
at project.MainPanel.calculateButtonActionPerformed(MainPanel.java:198)
at project.MainPanel.access$200(MainPanel.java:32)
at project.MainPanel$3.actionPerformed(MainPanel.java:97)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:1882)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2202)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:420)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:258)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:236)
at java.awt.Component.processMouseEvent(Component.java:5602)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3135)
at java.awt.Component.processEvent(Component.java:5367)
at java.awt.Container.processEvent(Container.java:2010)
at java.awt.Component.dispatchEventImpl(Component.java:4068)
at java.awt.Container.dispatchEventImpl(Container.java:2068)
at java.awt.Component.dispatchEvent(Component.java:3903)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4256)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:3936)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:3866)
at java.awt.Container.dispatchEventImpl(Container.java:2054)
at java.awt.Window.dispatchEventImpl(Window.java:1801)
at java.awt.Component.dispatchEvent(Component.java:3903)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:463)
at java.awt.EventDispatchThread.pumpOneEventForHierarchy(EventDispatch! Thread.j ava:269)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:190)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:184)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:176)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:110)\
I do not know why this is happening. Could the fact that I compiled the program on a Windows computer be the problem? That is the only thing that I could think of.
Under OS X the default version of Java is Java 1.5.
The only good Way to ensure the right jvm is with java Web start.
Without being able to test this, I would assume that this is because the Java version that you compiled this under is greater than the Java version that you are running on your Macintosh.
I suggest that you check the versions of each and make sure that the version which you are running under Mac OS is the same, or later.
Alternatively, you could try using the "-target" option for javac to set an older version and see if that helps.
You have to upgrade your java version to 1.6 minimum. First of all you check your java version on terminal by typing "java -version" if you don't have the 1.6, go to the Spotlight, write java and in Java Preferences drag and drop Java SE 6 to the top of the list, and it was done. Exit and that's it.