JAR文件未在crontab执行时从Scanner（System.in）读取输入

Question

I have created some application, which is reading from System.in using the following method:

    Scanner input = new Scanner(System.in);

    while (input.hasNextLine()) {

        String line = input.nextLine();

    }

Input data is being passed with linux command:

cat -A /home/someuser/somefile.txt | java -classpath "$CLASSPATH" com.test.Main

The crontab entry looks like:

MAILTO=someuser
CLASSPATH="/home/someuser/test.jar:/usr/share/java/jdom.jar:/usr/share/java/mysql-connector-java.jar"

0,10,20,30,40,50 * * * * cat -A /home/someuser/somefile.txt | java -classpath "$CLASSPATH" com.test.Main  >/home/someuser/output.txt

The permissions for the files shows the following:

-rw-r--r-- 1 someuser serhiy 8385601 2011-02-07 10:57 /home/someuser/somefile.txt

Everything is working fine on my machine(Ubuntu 9), but after installation on another machine Ubuntu 8, I figured out that program starts but seems not to be reading anything. I have triple checked all configurations and all permissions and the result still the same. When I run command manually everything is working, when it's ran by crontab it seems not reading input. Anyone experienced this issues before?

Thanks for any help
Serhiy.

Answer 1

Are you defining the variables in crontab ? That does not seem right.

1) Move the command to a shell script and invoke the shell command from cron, eg

*/10 * * * * /home/someuser/some_script.sh >/home/someuser/some_script.cronoutput 2>&1

2) Contents of some_script.sh ; make sure the execute bit is set

#!/bin/sh
export MAILTO=someuser  
export CLASSPATH="/home/someuser/test.jar:/usr/share/java/jdom.jar:/usr/share/java/mysql-connector-java.jar"  

cat -A /home/someuser/somefile.txt | java -classpath "$CLASSPATH" com.test.Main  >/home/someuser/output.txt