PHP Word to pdf-php perform exec to turn Word into PDF permissions issue

execphp word go pdfphpexec permissions

Server: ubuntu14.04
php:5.4
apache:2.0
I followed the online search method to install the jdk1.7.0_79,jodconverter-2.2.2, and then use root login to the server, directly enter the command java-jar/alidata1/source/jodconverter-2.2.2/ lib/jodconverter-cli-2.2.2.jar/var/www/wwwroot/upload/doc/test.doc/var/www/wwwroot/upload/doc/' Test.pdf can be transferred, but put this command in the PHP file will not be executed, the return value is always int (127), the result returned with WhoAmI is Www-data, and then I put the server wwwroot, Source is changed from root to Www-data, and the result is int (127),
Shell_exec (' WhoAmI ');
EXEC (' java-jar/alidata1/source/jodconverter-2.2.2/lib/jodconverter-cli-2.2.2.jar/var/www/wwwroot/upload/doc/ Test.doc/var/www/wwwroot/upload/doc/test.pdf 2>/var/www/wwwroot/log.txt ', $arr, $res);
Var_dump ($arr, $res);
?>
This catch log, get is sh:1: Java:not found.
Is there any great God who knows whether this is a matter of authority or not, and how should it be adjusted? Thank!

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