A very common problem is resolving a source, which means finding a source using a URI. The source resolver of Avalon Excalibur is a component helping you in this task. It resolves sources from a given URI. The URI can use all available protocols of the JRE. In addition own protocols can be plugged-in. So using the standard protocols like HTTP, FTP or file can be handled in the same way, like dealing with custom, self-build protocols such as myxmldatabase://root/documents/test.xml.