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NullGuards

Module NullGuards

Provides classes and predicates for null guards.


                                import semmle.code.java.dataflow.NullGuards

SSA	Provides classes and predicates for SSA representation (Static Single Assignment form).
java	Provides all default Java QL imports.

alwaysNullExpr	Gets an expression that is always `null`.
basicNullGuard	Gets an expression that directly tests whether a given expression, `e`, is null or not.
basicOrCustomNullGuard	Gets an expression that directly tests whether a given expression, `e`, is null or not.
clearlyNotNull	Holds if `v` is an SSA variable that is provably not `null`.
clearlyNotNull	Holds if `v` is an SSA variable that is provably not `null`.
clearlyNotNullExpr	Gets an expression that is provably not `null`.
clearlyNotNullExpr	Gets an expression that is provably not `null`.
directNullGuard	Gets an expression that directly tests whether a given SSA variable is null or not.
enumConstEquality	Gets an equality test between an expression `e` and an enum constant `c`.
guardSuggestsVarMaybeNull	`guard` is a guard expression that suggests that `v` might be null.
instanceofExpr	Gets an instanceof expression of `v` with type `type`
nullCheckMethod	Holds if the evaluation of a call to `m` resulting in the value `branch` implies that the argument to the call is guaranteed to be null if `isnull` is true, and non-null if `isnull` is false.
nullGuard	Gets a `Guard` that tests (possibly indirectly) whether a given SSA variable is null or not.
varEqualityTestExpr	Gets an expression of the form `v1 == v2` or `v1 != v2`. The predicate is symmetric in `v1` and `v2`.