遇到这样错误了
500 Servlet Exception
Resin can't load com.sun.tools.javac.Main. Usually this means that the
JDK tools.jar is missing from the classpath, possibly because of using
a JRE instead of the JDK. You can either add tools.jar to the classpath
or change the compiler to an external one with <java compiler='javac'/>
or jikes.