Could not find main class Java

Question

I have two classes Pair.java and Users.java where Users.java has the main program. Both these java files are under the package userdetails.

In unix, I compiled it using the command

javac -d . -classpath avro-1.7.5.jar:lib/*:jackson-core-asl-1.9.13.jar:lib/* Pair.java Users.java

the class are under the folder userdetails. I tried to run using the command

java  -classpath avro-1.7.5.jar:lib/*:jackson-core-asl-1.9.13.jar:lib/* userdetails.Users

I'm getting error

Could not find main class userdetails.Users

Kindly help me.

source code :-

import java.io.File; 
import java.io.IOException; 
import org.apache.avro.file.DataFileReader; 
import org.apache.avro.file.DataFileWriter; 
import org.apache.avro.io.DatumReader; 
import org.apache.avro.io.DatumWriter; 
import org.apache.avro.specific.SpecificDatumReader; 
import org.apache.avro.specific.SpecificDatumWriter; 
import org.apache.avro.util.Utf8;
public class Users {
 public void createUser() {
            userdetails.Pair datum = new userdetails.Pair(new Utf8("L"), new Utf8("R"));
            DatumWriter writer = new SpecificDatumWriter();
            DataFileWriter fileWriter = new DataFileWriter(writer);



            try {
                    fileWriter.create(datum.getSchema(), new File("users.avro"));
                    fileWriter.append(datum);
                    System.out.println(datum);
                    fileWriter.close();
            } catch (Exception e) {
                    // TODO Auto-generated catch block
                    System.out.println("ERROR");
                    e.printStackTrace();
            }         }

    public static void main(String[] args) {
            Users user = new Users();
            user.createUser();
    }
}

import java.io.File; import java.io.IOException; import org.apache.avro.file.DataFileReader; import org.apache.avro.file.DataFileWriter; import org.apache.avro.io.DatumReader; import org.apache.avro.io.DatumWriter; import org.apache.avro.specific.SpecificDatumReader; import org.apache.avro.specific.SpecificDatumWriter; import org.apache.avro.util.Utf8; public class Users { public static void main(String[] args) { Users user = new Users(); user.createUser(); } } — user2401464, Nov 14 '13 at 10:04
now please edit your question and put the remaining part of your code there — Hussain Akhtar Wahid 'Ghouri', Nov 14 '13 at 10:06
Read this stackoverflow question [could not find main][1] [1]: http://stackoverflow.com/questions/3005433/java-problem-could-not-find-main-class-helloworld — Ashish, Nov 14 '13 at 10:22

score 2 · Answer 1 · answered Nov 14 '13 at 10:11

2

When you specify a classpath, the current working directory is not automatically contained any more, so you must add it to the classpath:

java  -classpath avro-1.7.5.jar:lib/*:jackson-core-asl-1.9.13.jar:lib/*:. userdetails.Users

answered Nov 14 '13 at 10:11

isnot2bad

24,105
2
29
50

score 0 · Answer 2 · answered Nov 14 '13 at 10:20

0

You say both classes are under the package "userdetails", but there is no package declaration at the beginning of your source. Both Pair.java and User.java should begin with the line:

package userdetails;

Check out the Java Packages Tutorial

answered Nov 14 '13 at 10:20

vangelion

255
2
7

Could not find main class Java

2 Answers2