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*obscure* : One scoped identifier obscures another identifier in a containing scope if the two identifiers are the same, but theythe referobsucring toidentifier 
classdoes field hides a field in a superclass if they have the same identifier. The hidden field is not accessible from the class. Likewise, a class method hides a method in a superclass if they have the same identifier but incompatible signatures. The hidden method is not accessible from the class. See \[[JLS 2005not [shadow|BB. Definitions#shadow] the obscured identifier. This can happen if the obscuring identifier is a variable while the obscured identifier is a type, for example. See \[[JLS 2005|AA. Bibliography#JLS 05]\] section [6.3.2|http://java.sun.com/docs/books/jls/third_edition/html/names.html#6.3.2] for more information.

*override* : One class method overrides a method in a superclass if they have compatible signatures. The overridden method is still accessible from the class via the {{super}} keyword. See \[[JLS 2005|AA. Bibliography#JLS 05]\] section [8.4.8.1|http://java.sun.com/docs/books/jls/third_edition/html/classes.html#8.4.8.1] for the formal definition. Contrast with [hide|BB. Definitions#hide].

*sequential consistency* : "Sequential consistency is a very strong guarantee that is made about visibility and ordering in an execution of a program. Within a sequentially consistent execution, there is a total order over all individual actions (such as reads and writes) which is consistent with the order of the program, and each individual action is atomic and is immediately visible to every thread. \[...\] If a program is correctly synchronized, then all executions of the program will appear to be sequentially consistent (§17.4.3)." \[[JLS 2005|AA. Bibliography#JLS 05]\]. Sequential consistency implies there will be no compiler optimizations in the statements of the action. Adopting sequential consistency as the memory model and disallowing other primitives can be overly restrictive because under this condition, the compiler is not allowed to make optimizations and reorder code \[[JLS 2005|AA. Bibliography#JLS 05]\].