The following piece of code fails with an InvalidKeySpecException:

-------------
        KeyPairGenerator kpg = KeyPairGenerator.getInstance("RSASSA-PSS");
        KeyFactory kf = KeyFactory.getInstance("RSASSA-PSS");
        kpg.initialize(new RSAKeyGenParameterSpec(2048,
                RSAKeyGenParameterSpec.F4,
                new PSSParameterSpec(
                        "SHA-384", "MGF1",
                        new MGF1ParameterSpec("SHA-384"),
                        48, PSSParameterSpec.TRAILER_FIELD_BC)));
        kf.generatePublic(new X509EncodedKeySpec(
                kpg.generateKeyPair().getPublic().getEncoded()));
---------------

Caused by: java.security.ProviderException: Unsupported algorithm 1.2.840.113549.1.1.10
at java.base/sun.security.rsa.RSAUtil$KeyType.lookup(RSAUtil.java:66)
at java.base/sun.security.rsa.RSAUtil.getParamSpec(RSAUtil.java:142)
at java.base/sun.security.rsa.RSAUtil.getParamSpec(RSAUtil.java:133)
at java.base/sun.security.rsa.RSAPublicKeyImpl.<init>(RSAPublicKeyImpl.java:130)

Cause
=====

This is because when the key is read, the parameters of the AlgorithmId is instantiated with the OID (in AlgorithmId::decodeParams, algParams = AlgorithmParameters.getInstance(algidString)), so its getAlgorithm() always returns the OID string, and cannot be recognized by RSAUtil::lookup.

Suggested fix:
===========

diff --git a/src/java.base/share/classes/sun/security/rsa/RSAUtil.java b/src/java.base/share/classes/sun/security/rsa/RSAUtil.java
--- a/src/java.base/share/classes/sun/security/rsa/RSAUtil.java
+++ b/src/java.base/share/classes/sun/security/rsa/RSAUtil.java
@@ -63,6 +63,9 @@
                 }
             }
             // no match
+ if (name.equals(AlgorithmId.RSASSA_PSS_oid.toString())) {
+ return PSS;
+ }
             throw new ProviderException("Unsupported algorithm " + name);
         }
     }