从PHP调用Java程序

Question

I created a Java program which sends an email from my gmail account. I programmed it in Eclipse and it works fine. But when I attempt to call it from PHP i get the following error:

Exception in thread "main" java.lang.NoClassDefFoundError: javax/mail/Address
  at sendVerificationEmail.main(sendVerificationEmail.java:3)
Caused by: java.lang.ClassNotFoundException: javax.mail.Address
  at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
  at java.security.AccessController.doPrivileged(Native Method)
  at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
  at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
  at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
  at java.lang.ClassLoader.loadClass(ClassLoader.java:266)

Here's the command Eclipse uses:

/usr/lib/jvm/java-6-openjdk/bin/java -agentlib:jdwp=transport=dt_socket,suspend=y,address=localhost:53094 -Dfile.encoding=UTF-8 -classpath /home/****/dir/to/program/java/bin:/home/****/dir/to/program/java/lib/javamail-1.4.4/mail.jar sendEmail

Here's the command PHP uses:

exec("java -classpath /home/****/dir/to/program/java/bin:/home/****/dir/to/program/java/lib/javamail-1.4.4/mail.jar sendVerificationEmail $name $email $comments");

Answer 1

You need to add the jar file containing the javax.mail... classes to your command:

For example the following will add the current directory (.) and javax.jar to the classpath:

(linux)   java -classpath .:javax.jar com.me.MyMailClient
(windows) java -classpath .;javax.jar com.me.MyMailClient

javax.jar is not what it will be called, that's just to show you where you'd put it. To find out where Eclipse is getting the javax.mail.* items, look at your Project->Properties->Build Path->Libraries tab. One of the jars listed there is what you need (you can see the contents of jars by unzipping). It might be called mail.jar, j2ee.jar, javamail.jar - there are a few different likely candidates. Since your test app is simple it should have few dependencies so you'll be able to spot it easily.

You will need to put a copy of this jar file near run script (the above example assumes it is in the same directory as you are running the java command).

Hope that helps.

Answer 2

The problem is that your webserver (for ex APACHE) is not able to locate the java class files in the class path what you have to do is either change your class path using CLASSPATH environment variable to a location where the Jar/classes is there, or put you classes/jar file to the lib directory of the APACHE (APACHE/lib) and restart the server .

hope it helps