On Wed, 12 Jan 2022 19:31:31 GMT, Valerie Peng <valer...@openjdk.org> wrote:
>> If so, then the `if` block will be true and the spec object is casted to >> your specified class (`AlgorithmParameterSpec.class` or `Object.class`) and >> it always succeeds. >> >> This is exactly what I want to achieve. In fact, this bug and the other >> `getInstance(oid)` bug have the same root. I was trying to decode an >> algorithm identifier from its encoding. First, the encoding of the algorithm >> is in OID so `AlgorithmParameters.getInstance()` must support OID. Second, I >> want to get the spec from the parameters without knowing the algorithm name >> and the child `AlgorithmParametersSpec` class type, so >> `AlgorithmParameters::getParameterSpec` must support >> `AlgorithmParameterSpec.class` as the argument. >> >> Otherwise, the program needs to know name and parameter spec type on all >> supported algorithms. > > Interesting... In hindsight, the cast call sort of confirms that the intended > ordering is the suggested one. The check ensures casting always succeeds. The fact that this has not been noticed for such a long time means everyone is using the exact subclass type when calling the method. ------------- PR: https://git.openjdk.java.net/jdk/pull/7037
