Since it depends on Gentics Mesh the portal startup is described here in short.
With the recommended project setup the startup sequence looks as follows:
Initialize logging
Load the main server configuration
Perform dependency injection
Wait for Gentics Mesh to be ready
Call the start() method of the BoostrapInitializer` implementation
The Gentics Portal | java waits for Gentics Mesh to be ready before actually starting itself.
For Gentics Mesh to be ready it has to be
reachable for the portal, and
all the plugins must have been fully registered
The portal will check the above conditions every few seconds until Mesh becomes ready, and will then continue with the startup.
When a portal implementation depends on certain Gentics Mesh plugins, those can
be configured with the
mesh.requiredPlugins setting. This setting takes a list of plugin IDs which
must be present and fully registered in the used instance of Gentics Mesh.
This list may be empty but it is strongly advised to list the needed plugins.
When mesh.requiredPlugins is empty, all present plugins in the Gentics Mesh
instance still need to be fully registered before the portal will start, but
there is a slim chance, that the portal queries the plugin status when
Gentics Mesh has not yet begun loading the plugins and answers with an empty list.
In this case the Gentics Portal | java will wait for a few seconds and query the plugin status again to minimize the chance of a wrongly empty list of plugins.