On a CentOS 7 server, I have a Java program /path/to/parent/bin/mainpackage/SendText.class
that works perfectly when I call it from a c program located at /path/to/parent/bin
using the syntax:
system("java -cp .:\"/path/to/parent/dependencies/*\" mainpackage.SendText username pincode");
But the problem is that the C program cannot be located in /path/to/parent/bin
. Instead, the C program must be located in /path/to/parent/
. How can I change the syntax so that the Java program will run when called from /path/to/parent/
?
Here is what I have done to set things up so far:
The Java program was compiled from /path/to/anotherparent/
using the command
javac -d bin -cp .:/path/to/anotherparent/dependencies/twilio-java-sdk-3.4.5.jar:/path/to/anotherparent/dependencies/httpcore-4.1.2.jar SendText.java
I then created the destination and copied SendText.class and its dependencies to the destination as follows:
[user@domain somedir]$ mkdir /path/to/parent/bin/
[user@domain somedir]$ mkdir /path/to/parent/bin/mainpackage
[user@domain somedir]$ sudo cp /home/username/javacode/bin/mainpackage/SendText.class /path/to/parent/bin/mainpackage
[user@domain somedir]$ sudo mkdir /path/to/parent/dependencies
[user@domain somedir]$ sudo cp -R /home/username/javacode/dependencies/* /path/to/parent/dependencies
Next, I created the C program atest.c
in /path/to/parent/
as follows:
[user@domain somedir]$ cd /path/to/parent
[user@domain parent]$ sudo nano atest.c
int main (void){
char jcmd[256] = "java -cp .:\"/path/to/parent/dependencies/*\" mainpackage.SendText username pincode";
printf(jcmd);
system(jcmd);
return 0;
}
Ctrl-X to save the program
I compiled the C program and tried to run it from /path/to/parent/
as follows:
[user@domain parent]$ sudo cc atest.c -o atest
[user@domain parent]$ ./atest
Error: Could not find or load main class mainpackage.SendText
java -cp .:"/path/to/parent/dependencies/*" mainpackage.SendText username pincode
To confirm that the problem is the location of the C file, I did the following:
[user@domain parent]$ sudo cp atest bin
[user@domain parent]$ cd /path/to/parent/bin
[user@domain bin]$ ./atest
Program runs successfully from /path/to/parent/bin
So what do I change in order to get the Java program to run successfully when it is called from /path/to/parent/
with the command ./atest
?
javac -d bin ...
That means that bin
, as an absolute path, must appear in the CLASSPATH when you run it. Better still, create a JAR file for the contents of bin
, put it whenever you like, and provide the absolute path of the JAR file as a CLASSPATH element when you execute.