Invalid RSASSA-PSS salt length parameter: Unsupported content digest algorithm: SHA256

Hello,

I want to validate signature of JWS structure with PS256 algorithm. So i use RSASSAVerifier. But when i want to verify, throws exception like below. Is something wrong with my code?

Here is my code;

fun jwsValidateSignature(jws: String): String {
        val jwsObject: JWSObject
        try {
            jwsObject = JWSObject.parse(jws)
        } catch (e: ParseException) {
            throw RuntimeException("JWS parsing failed")
        }

        try {
            val verifier: JWSVerifier?
            val alg = jwsObject.header.algorithm
            if (alg == JWSAlgorithm.PS256 || alg == JWSAlgorithm.RS256) {
                val publicKey = X509CertUtils.parse(jwsObject.header.x509CertChain[0].decode()).publicKey as RSAPublicKey
                verifier = RSASSAVerifier(publicKey)
            } else if (alg == JWSAlgorithm.ES256) {
                verifier = ECDSAVerifier(ECKey.parse(jwsObject.header.jwk.toJSONString()))
            } else {
                // unsupported algorithm
                throw RuntimeException()
            }
            if (!jwsObject.verify(verifier)) {
                throw RuntimeException("JWS validation failed.")
            }
        } catch (e: Exception) {
            throw RuntimeException("JWS validation failed.")
        }

        return jwsObject.payload.toString()
    }

Exception

java.security.InvalidAlgorithmParameterException: Unsupported content digest algorithm: SHA256
    at com.android.org.conscrypt.OpenSSLSignature$RSAPSSPadding.engineSetParameter(OpenSSLSignature.java:386)
    at java.security.Signature$Delegate.engineSetParameter(Signature.java:1398)
    at java.security.Signature.setParameter(Signature.java:1021)
    at com.nimbusds.jose.crypto.impl.RSASSA.getSignerAndVerifier(RSASSA.java:98)
    at com.nimbusds.jose.crypto.RSASSAVerifier.verify(RSASSAVerifier.java:159)
    at com.nimbusds.jose.JWSObject.verify(JWSObject.java:353)
    at android.os.AsyncTask$2.call(AsyncTask.java:333)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:245)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)
    at java.lang.Thread.run(Thread.java:764)

JWS Header

{
    "x5c":[
        "MIIFjjCCA3....",
        "MIIF3jCCA8...."
    ],
    "alg":"PS256"
}

Thank you.

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