001package com.nimbusds.jose.jwk; 002 003 004import java.security.Key; 005import java.security.KeyPair; 006import java.util.Collections; 007import java.util.LinkedList; 008import java.util.List; 009 010import com.nimbusds.jose.JOSEException; 011 012 013/** 014 * Key converter. 015 */ 016public class KeyConverter { 017 018 019 /** 020 * Converts the specified list of JSON Web Keys (JWK) their standard 021 * Java class representation. Asymmetric {@link RSAKey RSA} and 022 * {@link ECKey EC key} pairs are converted to 023 * {@link java.security.PublicKey} and {@link java.security.PrivateKey} 024 * (if specified) objects. {@link OctetSequenceKey secret JWKs} are 025 * converted to {@link javax.crypto.SecretKey} objects. Key conversion 026 * exceptions are silently ignored. 027 * 028 * @param jwkList The JWK list. May be {@code null}. 029 * 030 * @return The converted keys, empty set if none or {@code null}. 031 */ 032 public static List<Key> toJavaKeys(final List<JWK> jwkList) { 033 034 if (jwkList == null) { 035 return Collections.emptyList(); 036 } 037 038 List<Key> out = new LinkedList<>(); 039 for (JWK jwk: jwkList) { 040 try { 041 if (jwk instanceof AssymetricJWK) { 042 KeyPair keyPair = ((AssymetricJWK)jwk).toKeyPair(); 043 out.add(keyPair.getPublic()); // add public 044 if (keyPair.getPrivate() != null) { 045 out.add(keyPair.getPrivate()); // add private if present 046 } 047 } else if (jwk instanceof SecretJWK) { 048 out.add(((SecretJWK)jwk).toSecretKey()); 049 } 050 } catch (JOSEException e) { 051 // ignore and continue 052 } 053 } 054 return out; 055 } 056}