Source: javaindos.
Answer from Nicholas Kadaeux on Stack OverflowLet's say your file is in C:\mywork\
Run Command Prompt
CopyC:\> cd \myworkThis makes C:\mywork the current directory.
CopyC:\mywork> dirThis displays the directory contents. You should see filenamehere.java among the files.
CopyC:\mywork> set path=%path%;C:\Program Files\Java\jdk1.5.0_09\binThis tells the system where to find JDK programs.
CopyC:\mywork> javac filenamehere.javaThis runs javac.exe, the compiler. You should see nothing but the next system prompt...
CopyC:\mywork> dirjavac has created the filenamehere.class file. You should see filenamehere.java and filenamehere.class among the files.
CopyC:\mywork> java filenamehereThis runs the Java interpreter. You should then see your program output.
If the system cannot find javac, check the set path command. If javac runs but you get errors, check your Java text. If the program compiles but you get an exception, check the spelling and capitalization in the file name and the class name and the java HelloWorld command. Java is case-sensitive!
Source: javaindos.
Let's say your file is in C:\mywork\
Run Command Prompt
CopyC:\> cd \myworkThis makes C:\mywork the current directory.
CopyC:\mywork> dirThis displays the directory contents. You should see filenamehere.java among the files.
CopyC:\mywork> set path=%path%;C:\Program Files\Java\jdk1.5.0_09\binThis tells the system where to find JDK programs.
CopyC:\mywork> javac filenamehere.javaThis runs javac.exe, the compiler. You should see nothing but the next system prompt...
CopyC:\mywork> dirjavac has created the filenamehere.class file. You should see filenamehere.java and filenamehere.class among the files.
CopyC:\mywork> java filenamehereThis runs the Java interpreter. You should then see your program output.
If the system cannot find javac, check the set path command. If javac runs but you get errors, check your Java text. If the program compiles but you get an exception, check the spelling and capitalization in the file name and the class name and the java HelloWorld command. Java is case-sensitive!
To complete the answer :
The Java File
Copy
TheJavaFile.javaCompile the Java File to a *.class file
Copy
javac TheJavaFile.java- This will create a
TheJavaFile.classfile
- This will create a
Execution of the Java File
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java TheJavaFileCreation of an executable
*.jarfileYou've got two options here -
With an external manifest file :
Create the manifest file say - MANIFEST.mf
The MANIFEST file is nothing but an explicit entry of the Main Class
jar -cvfm TheJavaFile.jar MANIFEST.mf TheJavaFile.class
Executable by Entry Point:
jar -cvfe TheJavaFile.jar <MainClass> TheJavaFile.class
To run the Jar File
Copy
java -jar TheJavaFile.jar
Videos
Second Edit: May have fixed the Environment Variables to work with JAVA_HOME. Minor change to what was printed but was able to run the file like so:
C:\Users\Test>cd Documents\MyFirstProgramFolder C:\Users\Test\Documents\MyFirstProgramFolder>java MyFirstProgram We did it! Again! Number 3!
Again, making sure I was in the right directory was the first issue, but now I may have the Environment Variables fixed. I hope at least. Thank you again everyone.
Edit: Have my issue mostly solved. I am able to compile and run the code. cd-ing to the correct directory seemed to be the issue in the command prompt and that is all I really need for now. Thank you to everyone who took the time try to help me!
Hello! I am new to learning Java but have been stuck on a single issue for the past day and a half. I have recently started reading Head First Java to try and teach myself Java. I took a single programming class that was taught in Java 3-4 years ago. All of the programming experience I have has always been in some sort of IDE. In Head First Java they want you to work through the command line after writing code. I have been entirely unsuccessful at setting up Java to work through the command prompt. I have now tried to download 2-3 different JDK's, followed 2-3 tutorials on how to just get "Hello World" to print, and followed a guide on how to set up the Java Environment. None have been successful and I am frequently met with the below errors/issues when I try to parse together my understanding trying to fix the issue. I would really like to learn how to actually do things without the need of an IDE. Any help at all would be greatly appreciated! So the question summed up, is more or less where am I going wrong for setting up the Java environment, or JVM?
In the Command Prompt:
C:\Users\Test>"C:\Program Files\Java\jdk1.8.0_161\bin"\Javac MyFirstProgram.java
javac: file not found: MyFirstProgram.java
Usage: javac <options> <source files>
use -help for a list of possible options
In Windows Powershell:
PS C:\Users\Test\Documents\MyFirstProgramFolder> "C:\Program Files\Java\jdk1.8.0_161\bin"\javac MyFirstProgram.java
At line:1 char:41
+ "C:\Program Files\Java\jdk1.8.0_161\bin"\javac MyFirstProgram.java
+ ~~~~~~
Unexpected token '\javac' in expression or statement.
+ CategoryInfo : ParserError: (:) [], ParentContainsErrorRecordException
+ FullyQualifiedErrorId : UnexpectedToken
Below are some of the websites I have tried:
https://www.instructables.com/How-to-Make-Your-First-Computer-Program/ - This instructables link is what I just used to receive the above responses.
https://www.tutorialspoint.com/java/java_environment_setup.htm
https://www.geeksforgeeks.org/setting-environment-java/
The Code:
class MyFirstProgram {
public static void main(String[] args) {
System.out.println("Hello, World");
}
}Hey guys,
I'm having trouble understanding how to run a program in a terminal or on command prompt with Windows. Can someone give me a detailed explanation on how to run a program on command prompt/terminal?
Thanks!
javac is the Java compiler. java is the JVM and what you use to execute a Java program. You do not execute .java files, they are just source files.
Presumably there is .jar somewhere (or a directory containing .class files) that is the product of building it in Eclipse:
java/src/com/mypackage/Main.java java/classes/com/mypackage/Main.class java/lib/mypackage.jar
From directory java execute:
java -cp lib/mypackage.jar Main arg1 arg2
A very general command prompt how to for java is
javac mainjava.java
java mainjava
You'll very often see people doing
javac *.java
java mainjava
As for the subclass problem that's probably occurring because a path is missing from your class path, the -c flag I believe is used to set that.
I hope this can help somebody, a little late but, just I had this problem, ok my solution it next: 1. Run your code normally and copy the command line that the IntellijIDEA made, see the screenshot.
2.Copy and paste the command line that it uses to use with your params.
Three issues:
You have to specify the fully qualified class name (that means including the package name) to the
javacommand. It looks like yourmyjavaclass is in a packagecom.myexample.test. So its fully qualified name iscom.myexample.test.myjava.When you run the
javacommand you have to be in the directory that is at the base of the package hierarchy (or put that directory on the classpath).You're using the
srcdirectory, which contains.javasource files, but thejavacommand expects compiled.classfiles, so you need to use the project's output directory. Its location in your project will depend on your IDE and configuration but it will contain same-named structure as insidesrc, except with.classfiles instead of.javafiles.
In your case, navigate to:
CopyC:\myjava\sampl1\out\production\
Then run:
Copyjava com.myexample.test.myjava