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Theme Resolvers are called upon to find all themes they can.
Implementations
There exists only one implementation of the IThemeManager:
org.pentaho.platform.web.html.themes.DefaultThemeManager (Source)
And two implementations of IThemeResolver:This Manager caches all results from the resolvers in the Platform CacheManager to reduce memory overhead.
org.pentaho.platform.web.html.themes.PluginThemeResolver (Source)
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