[Relearn Spring] 三 Resource

[Relearn Spring] 3 Resource1. Resource is actually a more powerful version of java.net.URL.Whats

[Relearn Spring] 3 Resource
1. 'Resource' is actually a more powerful version of java.net.URL.
    What's more, Spring suggests you use it as a generic utility class, even without Spring.

2. Built-in Implementations.
    a.UrlResource
    b.ClasspathResource
    c.FileSystemResource
    d.ServletContextResource
    e.InputStreamResource
    f.ByteArrayResource