CLASSPATH，Java Buld Path（eclipse）和WEB-INF \ LIB：使用什么，何时以及为什么？

I recently switched to J2EE from .NET, and am confused about where to put JAR files. I know that the CLASSPATH, WEB-INF, and Eclipse's Java Web Path are all places where JARs can be stored, but I'm confused about which folder to use, when, and why.I recently switched to J2EE from .NET, and am c