Javac Puns

when I run javac -version in the terminal I just get this error:

The operation couldn’t be completed. Unable to locate a Java Runtime that supports javac.

can anyone help fix this I am trying to make a mod for Minecraft with mcp918

MacOS version: Monterey 12.1

I'm trying to compile a basic Servlet but receive the error "Cannot find symbol HttpServlet".

In TestServlet.java I'm importing the following.

 import java.io.*; import javax.servlet.*; import javax.servlet.http.*;

I try to compile with javac -cp .;[Tomcat-Dir]\lib\servlet-api.jar package\TestServlet.java

I have tried to set the Classpath with Windows environment variables as well, with the same outcome.

I already installed several jdks, like jdk-openjdk, jdk...But no matter which one I chose, i could not use the javac command.How do I install javac on my archlinux machine?

For some reason it now works, I did nothing on purpose, idk what was the fix, but I can confirm now that jdk-openjdk works also for me :P

I know you can invoke it using java -m jdk.compiler/com.sun.tools.sjavac.Main, but where I can find more information about it. Looks like it should support incremental compilation and it split between client and server.

Is it possible to use it in a Maven build?

http://openjdk.java.net/jeps/199

I am using visual studio code to see the .class file form in front of my eyes. Here is the code I wrote

public class rish { public static void main (String []args){ System.out.println("hello world"); } }

Then I wrote the command javac rish.java In the command terminal Instead of creating a rish.class file It did nothing and when I tried to run it using the command java rish.java The command prompt said : no class declared in source file.

Please help and tell me what is happening? Is there a .class file being created And if yes then where could it be??

I need to pass two javac args on each run: "--module-path ./lib" and "--add-module=javafx.controls". Is there a way to do this?

I'm new in Java and trying to run my first program but this error keeps popping up. I have added both JRE and JDK in path but i still cant run code. I'm using VSCode as my text editor.

Hello there!

I recently started my Computer Science studies and our Prof recommended us to use Linux for programming.

After installing Ubuntu on my Laptop i tried to start by writing a small HelloWorld program on the Terminal via nano. Done with that, i tried to compile it via javac but just got some errors like: theres no JDK installied and got some suggested commands to install it, after that I tried to compile it again but just got this error message:

/usr/bin/javac: 4: .: Can't open /usr/lib/java-wrappers/java-wrappers.sh

Now i'm getting a little frustrated, as I'm searching the for about an hour now to find any solution.

If anyone out there is able to help me, it would really brighten up the rest of my day.

I'm trying to pass that into the constructor of one of my attributes:

private AClass aClass = new AClass( Vector<MyClass>.class );

Another way I can think of doing this is instantiating a empty vector and calling .getClass() on it, but that seems wasteful. Is there another way to do what I'm trying to do here?

I'm building a simple java gui applications using AWT and Swing. Lets say I'm using java 13 and all the files are in a single folder and I'm compiling from the current directory with the command javac *.java or javac Driver.java

My problem is that after modifying and saving some of the .java files related to GUI elements the java compiler (javac) does not recompile those files and I'm forced to delete the .class files first and then compile to see the changes.

Unfortunately, running with just java Driver.java does not work because there are multiple files in the project.

I've tried writing a script to delete *.class files and then compile but that doesn't explain why javac does not detect the changes in the .java files related to a GUI.

Am I missing a concept? Thanks.

https://cwiki.apache.org/confluence/display/NETBEANS/Overview%3A+NetBeans+Structure

https://preview.redd.it/pfqiqif81in51.png?width=952&format=png&auto=webp&s=edf3f7744426f247be01d7e73ad68720567159b0

Sorry for the noob question.

I installed nb-javac when it was prompted.

I went to Apache's website where nb-javac is in the Netbeans installation folder, saying it's in java/modules/ext. I went to that folder, but it's not there?

Hey all,

I'm currently shifting gears towards Java from some more dynamic languages. Until now, the main hesitation I've had with Java has been due to feeling overwhelmed at the depth of additional tooling commonly used with Java. Typically as I learn, I like to start as simple as possible and expand tooling as needed with the complexity it adds.

With Java though, I can't quite grasp if this is worth doing. I understand the basics of Java compiling using javac, but is this actually worth learning at all? It seems as though tools like Gradle and Maven seem to be the way to go. Is this true even for more basic projects?

Half of what I like to do with different languages are just very small exploratory projects or programs, where I'm just trying out a new library, but I have yet to find the developmental sweet spot with this with Java.

Any pointers?

So today is my first day with Java, and I am already confused and frustrated. I downloaded JDK and am using intelliJ. I wrote a simple program that prints a few words, which I literally copied from a powerpoint. I found where that .java file is, went into command prompt, and changed the directory to to where it is. I then tried javac and the file name and it gave me the title error. I'm sure many of you have seen or come across this, but I need your help.

I looked up solutions. I changed the system environment Variables Path, something I know very little about. I added the path to the bin folder, which I know is JDK. I'm still getting the error message. I've closed cmd, and tried several times. I've double checked the path, and it's in there. I'm really not sure what I'm doing wrong, and why this is so hard to even run the simplest program. Your help is greatly appreciated.

Im really new to java and ive been just trying to compile and run a small program in the windows 10 cmd prompt. I cant run the java after I complile because my versions are different, how would i fix this?

C:\>cd head first

C:\head first>javac bruh.java

C:\head first>java bruh

Error: A JNI error has occurred, please check your installation and try again

Exception in thread "main" java.lang.UnsupportedClassVersionError: bruh has been compiled by a more recent version of the Java Runtime (class file version 58.0), this version of the Java Runtime only recognizes class file versions up to 52.0

at java.lang.ClassLoader.defineClass1(Native Method)

at java.lang.ClassLoader.defineClass(Unknown Source)

at java.security.SecureClassLoader.defineClass(Unknown Source)

at java.net.URLClassLoader.defineClass(Unknown Source)

at java.net.URLClassLoader.access$100(Unknown Source)

at java.net.URLClassLoader$1.run(Unknown Source)

at java.net.URLClassLoader$1.run(Unknown Source)

at java.security.AccessController.doPrivileged(Native Method)

at java.net.URLClassLoader.findClass(Unknown Source)

at java.lang.ClassLoader.loadClass(Unknown Source)

at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)

at java.lang.ClassLoader.loadClass(Unknown Source)

at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)

C:\head first>java -version

java version "1.8.0_241"

Java(TM) SE Runtime Environment (build 1.8.0_241-b07)

Java HotSpot(TM) 64-Bit Server VM (build 25.241-b07, mixed mode)

C:\head first>javac -version

javac 14.0.2

I haven't really used the command line java and javac in a while since I use Ant or some other build tool. When did they make it so you could run the following:

java MyApp.java 

Instead of having to do

javac MyApp.java java MyApp 

I just updated from JDK11 to 14, but I guess this also worked in JDK11, just never tried it I guess.

I was directed here by a r/java bot.

I installed the following JDK on Windows 10:

C:\Program Files\AdoptOpenJDK\jdk-11.0.8.10-openj9

I am new to Java, so lots of error messages, which I like to peruse with my favoured power editor.

If I invoke javac from the DOS CMD shell and redirect stderr to a file, all is fine:

javac -classpath "c:\Program\ Files\...\cplex.jar" TestSetup.java 2> mk.out 

If I use Cygwin Bash to invoke it and redirect stderr to a file, it includes many ANSI codes. Among other things, it colorizes some text:

env -u TERM -u XTERM_SHELL -u XTERM_VERSION -u XTERM_LOCALE \
script -c \
   "javac \
      -classpath \
         '/c/Program Files/.../cplex.jar' \
      TestSetup.java" \
   mk.out

I can clean up the output using the Vim's command :term cat %, but I would prefer a less round-about solution:

1. How does javac decide not to output ANSI codes in one case but not another?
2. If it is environment variables, which one? I unset the most obvious ones above, but they don't seem to have any effect.

Other contextual details

For the Bash invocation above, I used script because the most obvious way of redirecting stderr sends output to the console and yields a 0-byte output file:

env -u TERM -u XTERM_SHELL -u XTERM_VERSION -u XTERM_LOCALE \
javac \
   -classpath \
      '/c/Program Files/.../cplex.jar' \
   TestSetup.java \
2>&1 >| mk.out

I have my Java path set up perfectly, I did a clean installation, I checked inside the bin folder and I have javac etc. and I can use javac from there but command prompt doesn't recognize it. Any help?

Basically I'm trying to import a package that is in a different directory, resulting in a java error: package does not exist. The package I'm trying to import is in \dir1\dir2 and the class I'm trying to import it in is in \dir1\dir3.

Wanted to start Java yesterday, tried a simple hello world program but javac outputs 1 error. I saw on a video ( using the Atom editor just like me ) in which the program was compiled using javac, and it automatically generated a class file.. not in my case. I don't know what I'm doing wrong and can't start a simple hello world.. any suggestions

Even with 100% Kotlin source code, will some of the generated files (Navigation, ViewBinding, R class, etc) prevent compilation to be purely kotlinc?

I can't even get past the Hello World without stumbling....

I'm typing in javac HelloWorld.java, as instructed by the textbook I'm using

I'm getting ';' expected between HelloWorld and Java, when it should be compiling the HelloWorld file.

I imagine that I'm making a really dumb error here and that it's a simple fix, and that I'll feel really stupid when somebody resolves this for me, but I'm stumped.

Edit: Solved, and yes I really do feel dumb, thanks everyone.