http://tmapi.org/features/automerge.  If this property is true, then the implementation will automatically merge two Topics if it detects that they should be merged. Implementations MUST ensure that this merging is transparent to the client application. What this means in practice is that when two Topics get merged, you should be able to use a reference to either Topic object to get to the new merged object. The circumstances under which two Topics get merged depends on the settings of the features under the http://tmapi.org/features/merge/ hierarchy. If this property is false, then whenever the implementation detects that two Topcics should be merged, it MUST raise an org.tmapi.core.TopicsMustMergeException.

http://tmapi.org/features/merge/byTopicName.  If this property is true, then the implementation MUST detect when two topic instances have topic names which match both in the scope of the name and the value of the name string, and, if XTM 1.1 is supported (http://tmapi.org/features/model/xtm1.1), the types are equal. Topics which have matching names must either be merged or a TopicsMustMergeException must be raised, depending on the value of the http://tmapi.org/features/automerge feature.

http://tmapi.org/features/readOnly.  If the value of this feature is true, then the TopicMapSystem will be created as a read-only system. No new TopicMaps can be added to it and existing TopicMaps can only be read and cannot be updated. Calls to createXXX(), addXXX() and remove() methods will result in an UnsupportedOperationException being raised.

http://tmapi.org/features/model/xtm1.0.  If the value of this feature is true, then the TopicMapSystem supports the data model for topic maps defined by the XTM 1.0 standard. Specifically this means that any name-based merging it supports must not require the names to be of the same type; and that the system does not support typed TopicName instances.

http://tmapi.org/features/model/xtm1.1.  If the value of this feature is true, then the TopicMapSystem supports the data model for topic maps currently being defined by ISO for the next version of ISO 13250 (commonly known as the Topic Maps Data Model or TMDM). The two main differences between XTM 1.0 and XTM 1.1 is that XTM 1.1 adds support for a type to be specified on a TopicName, and that under XTM 1.1 a Topic may have more than one value for the subjectLocators property.

http://tmapi.org/features/notation/URI.  If the value of this feature is true then the TopicMapSystem supports parsing and relative path resolution for URI notation addresses. Locators using this notation must specify the notation string "URI".