class file from cmd with the following command and i get the output:
The error is: "Error: Could not find or load main class CustomerManager.class"
Any idea how i could resolve this issue ?
java CustomerManager
Without the .class extension.
just type in cmd java CustomerManager , no need to add .class
In java command . character is shows a / character and use for path of target class.
For solve your problem, execute your command without .class and extension as following:
java CustomerManager
(You can found by a little searching in web, very pages that explain it.)
Inside your code , keep your class as Public and then execute
java CustomerManager
Also cross check in your IDE if there aren't any spaces before or after the class .
Hope this helps .
Related
I've just completed quite a large project using IntelliJ and said I'd give the command line statement for people without an IDE to run it (the project will be run on different machines by different people etc). I haven't used the command line in a while and so I'm a bit rusty. I've gotten a NoClassDefFoundError:wrong name and I've been looking at questions on S/O such as Why am I getting a NoClassDefFoundError in Java? but these don't seem to fix my problem. I'm using quite a few external libraries but I have them correctly imported when trying to run. There are many classes compiled but only one will be run so I presume I only run the "java" command on the Main class
java -cp
.;poi-3.17/lib/comms-codec-1.10.jar;poi-3.17/lib/commons-collections4-4.1.jar;poi-3.17/lib/commons-logging-1.2.jar;poi-3.17/lib/junit-4.12.jar;poi-3.17/lib/log4j-1.2.17.jar;poi-3.17/ooxml-lib/curvesapi-1.04.jar;poi-3.17/ooxml-lib/xmlbeans-2.6.0.jar;poi-3.17/poi-3.17.jar;poi-3.17/poi-ooxml-3.17.jar
bin/com/company/Main
Above is what I've been trying to get working so any suggestions on what I might be doing wrong would be appreciated
The whole exception is "Error: Could not find or load main class Main
Caused by: java.lang.NoClassDefFoundError: com/company/Main (wrong name: Main)"
Note, I'm using windows
#caius-brindescu is right, you have to specify the class like com.company.Main but also, you have to execute the class from inside the bin directory. So, run 'cd bin' and then your command and it should work.
This is like this because your PATH starts with a dot '.' which means here in this directory.
First, the separator for jar files for the -cp argument is the colon (:), not the semicolon (;). Using the semicolon will change how the arguments are parsed.
Also, when you run the main class, you have to specify the fully qualified name (com.company.Main), instead of the path to the class file. The class file will be resolved from the -cp arguments.
I'm newbie to Java. I have read all the documentations regarding specifing the classpath. But I'm still confused about my case. I'm trying to use the BuildIndex command that is part of semantic package, specifically this example,
java pitt.search.semanticvectors.BuildIndex -luceneindexpath $INDEX_MADE_ABOVE.
in here
The source of how to use the class is here https://github.com/semanticvectors/semanticvectors/wiki/InstallationInstructions#to-build-and-search-a-model
I'm trying to specify the classpath like:
java cp- {classpath} pitt.search.semanticvectors.BuildIndex -luceneindexpath $INDEX_MADE_ABOVE.
in here
But I'm not sure what the class path should be here. . The command line should have a class path, but thinking it should not be related to my project, it's part of the semantic vectors package. Do I need to clone that? its source code from the package here https://github.com/semanticvectors/semanticvectors/blob/master/src/main/java/pitt/search/semanticvectors/BuildIndex.java..
My trials was using the path of my project as the picture but didn't work. Another trial was using -jar jarName ,, got the same error: Could not find or load main class pitt.search.semanticvectors.BuildIndex. I appreciate the help as I'm confused and new to this.
In Java, classpath is the path pointing to either the directory or the jar file where your compiled java class files are located.
In your project, the class pitt.search.semanticvectors.BuildIndex is located in the jar file C:\Users\{yourusername}\Downloads\semanticvectors-5.8.jar. Therefore, the classpath is C:\Users\{yourusername}\Downloads\semanticvectors-5.8.jar.
Try something like
java -cp C:\Users\{yourusername}\Downloads\semanticvectors-5.8.jar pitt.search.semanticvectors.BuildIndex -luceneindexpath $INDEX_MADE_ABOVE
I think you mistyped cp- instead of -cp.
For more details how to use classpath, please refer to Java SE Documentation
I am trying to run a java program through the Terminal on Mac, yet getting:
Error: Could not find or load main class (MY CLASSNAME)
I compiled this application with Eclipse, and when I run this with Eclipse, it works fine.
Furthermore, I am in the right directory, as when I type "ls" in the Terminal, it lists all the files, includes the class file I am trying to run.
This is what I type:
java mainClass
I would very much appreciate help to solve this!
Thank you,
Dean
EDIT: Solution - instead of java mainClass, it must have package too: java startPackage.mainClass
Start by making sure you are at the directory above the top level package
If the class belongs to the package com.foo.bar, you want to be in the directory above com.
In your case, you want to be in the directory above startPack.
Then you need to use the fully qualified name to run the class...
java statPack.mainClass
For example...
Make sure you have the current directory inside your CLASSPATH.
java -cp . mainClass
To set this globally, you can use export CLASSPATH=$CLASSPATH:. inside .bash_profile.
Separately, if your class lives inside a package such as com.foo.bar, then you will need to go to the parent directory of com and run your application with the full path.
java com.foo.bar.mainClass
I too faced this on Mac machine and then what I had to do to make it work was:
Problem Statement:
I had one package xyz under the root of project i.e src/main/java and then inside xyz package I had one class Student.java
my current directory is /Users/username/projectname/src/main/java/xyz:
I can see Student.java exists here
and I compiled it using javac Student.java
Now I see class file has been created at this location. But when I try to run the class file using java Student
I get the error: Error: Could not find or load main class Student
Solution:
Now the solution is to go one step back in the directory and go to root path:/Users/username/projectname/src/main/java and run the command
java xyz.Student
and it will work.
Link to follow: https://javarevisited.blogspot.com/2015/04/error-could-not-find-or-load-main-class-helloworld-java.html
For people dumb like me, make sure you are typing java HelloWorld - and NOT java HelloWorld.class - to run the compiled file with the name HelloWorld.class. This is especially so if you are used to hitting the tab key to complete the file name, as the terminal will give you java HelloWorld.class if you hit the tab key for autocomplete after typing something like java He...
This answer is here because it took 3 sites, including this answer, and 25 mintues before I figured out what I was doing wrong.
Logic is easy, typing is hard.
Using the absolute path can also resolve this problem:
java -classpath /Users/xingliu/IdeaProjects/springproject/src/main/java/ startPackage.mainClass
Can someone please tell me why this java command in a .bat file won't run my java program on WinXP? I have all my jar files in a folder called lib and my class files in a package folder mypackage.
java -cp ".;.\lib\poi-3.7-20101029.jar;.\lib\jsr173_1.0_api.jar;..." mypackage.MyClassWithMain
I have tried all sorts of things to no avail. I get a ClassNotFound error as soon as the program attempts to use some of the classes in the jar files. So, I think there's something wrong with my -cp option. It does find my main().
I want to give this program to someone who doesn't know a thing about computers, so I want them to be able to double-click the .bat file and go.
I wrote everything on a mac without much problem.
I bet the moderator is going to slap me upside the head for this question, but I did search extensively for an answer to this.
Thanks you!
John
Sorry, I should have put in the entire command line:
java -cp ".;.\libs\jsr173_1.0_api.jar;.\libs\poi-3.7-20101029.jar;.\libs\poi-ooxml-3.7-20101029.jar;.\libs\poi-ooxml-schemas-3.7-20101029.jar;.\libs\resolver.jar;.\libs\xbean.jar;.\libs\xbean_xpath.jar;.\libs\xmlbeans-qname.jar;.\libs\xmlpublic.jar" excelsifter.ExcelSifterController
This is all on one line. I tried / instead of \, but that didn't seem to work. Everything I could find on this indicates that for windows you have to use the backslash.
All the dependencies are here, as far as I know. At least my mac doesn't complain when I use essentially the same command.
My directory containing my .bat file contains the excelsifter package (a folder called excelsifter) and the folder libs with all the jar files in it.
Thanks, John
Your starting string looks ok to me, try to check if there are other dependencies in the libraries you use as #Said mentioned. The best way is to search for class your java cannot find, probably you'll find it declaration in some other library you didn't included in your classpath.
I am facing this problem while trying to run my java file by writing java filename ....
I have read on many pages the possible ways this could be corrected but unfortunately I have been unable to correct my problem...
First of all I looked at my environment variables and observed that there was no CLASSPATH set and I had pointed PATH correctly to my jre as well as jdk bin in C:\
Second I am able to run javac filename.java and observe that .class file gets built in the local directory.
While writing javac -classpath . filename works writing java -classpath . filename (without .class) results in the same error.
I just don't know how to run my program in command prompt!!!!
Please do not give me links to the pages which have given the same answers that I have mentioned above as they do not work in my case.....
Please help....
Note that if your class resides in some package mypackage, you need to make sure the class file is inside mypackage/ and do
java -classpath . mypackage.YourClass
There is a bit little information in your post ... as said, a complete example would really help solving this. Some ideas:
Is class named filename? If not, you should make sure to call the right class name in the java command.
if you have strange characters in your class name (basically anything apart from A-Z, a-z, 0-9, _), it could be mangled by your file system and thus lead to java not being able to find it. Make sure that the class name is the same as the file name.
If you use packages, make sure the package names are congruent to your file structure (see latest questions with tag package for some examples).
Is your class public? If not, make it so. (This should give another error, though.)
Stating javac filename.java and java filename are not enough for this really.
We also need to know the contents of the filename.java or at least the first few lines.
This is the expected way to declare a class
public class Filename {
}
This is the way it would have to be to work given your example: java filename
public class filename {
}
This is could exist too, but you are probably just messing with us :)
public class SomethingElse {
}
Overall no matter what the filename is on the filesystem, the class has a name and that is the name that the java command is expecting. I would recommend using the upper case first letter form as it is clearer imo