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Note that this does not imply that heap pollution only occurs if an unchecked warning actually occurred. It is possible to run a program where some of the binaries were compiled by a compiler for an older version of the Java programming language, or by a compiler that allows the unchecked warnings to suppressed. This practice is unhealthy at best.
Overriding legacy classes and generifying the overriding method is no panacea as this is made illegal by the Java Language Specification [JLS 05]. It is best to avoid mixing generic and non-generic code.
Noncompliant Code Example
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