Resolving the External_Cache Toolkit Property

The following only applies to XDS Toolkit.

Resolving the External Cache uses the following logic:

SP1	EcExists	SP2	Result
Y	Y	Y	External_Cache from the SP1 toolkit.properties is used. Both the default toolkit.properties and the SP2 are ignored. This will preserve the expectation of the SP2 behavior.
Y	Y	N	External_Cache from the SP1 toolkit.properties is used. The default toolkit.properties is ignored.
Y	N	Y	The External_Cache from the SP2 is used and the SP1 toolkit.properties file's ExternalCache property is updated to this value because the SP1 External_Cache does not exist.
Y	N	N	Invalid External_Cache from the toolkit.properties system property means the user needs to update the External Cache manually using the Tool Configuration UI tool page. (This instruction is printed in the startup log message.)
N	Y	Y	The External_Cache from the default toolkit.properties is used because the directory exists. The reason being External_Cache should always be editable from the Toolkit UI
N	Y	N	External_Cache from the default toolkit.properties is used.
N	N	Y	The External_Cache from the system property is used and the default toolkit.properties file's ExternalCache property is updated to this value.
N	N	N	Bogus External_Cache from the default toolkit.properties means the user needs to update the External Cache manually using the Tool Configuration UI tool page. (This instruction is printed in the startup log message.)

Legend
SP1	Java System Property -DTOOLKIT_PROPERTIES is Present
EcExists	ExternalCache Java File Path exists (path could be from either the toolkit.properties file from SP1, if present, or the default toolkit.properties)
SP2	Java System Property -DEXTERNAL_CACHE is Present