Java tutorial
//package com.java2s; /* * * Copyright (C) 2015 Orange Labs * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * */ import java.math.BigInteger; import java.security.KeyFactory; import java.security.KeyPair; import java.security.SecureRandom; import java.security.spec.RSAPublicKeySpec; import org.json.JSONArray; import org.json.JSONObject; import android.util.Base64; public class Main { public static String getJwkPublic(KeyPair kp) { try { JSONObject jk = new JSONObject(); jk.put("kty", "RSA"); // generate random kid SecureRandom random = new SecureRandom(); String kid = new BigInteger(130, random).toString(32); jk.put("kid", kid); jk.put("e", "AQAB"); KeyFactory kfactory = KeyFactory.getInstance("RSA"); RSAPublicKeySpec kspec = (RSAPublicKeySpec) kfactory.getKeySpec(kp.getPublic(), RSAPublicKeySpec.class); jk.put("n", encodeB64(kspec.getModulus().toByteArray())); JSONArray ja = new JSONArray(); ja.put(jk); JSONObject jo = new JSONObject(); jo.put("keys", ja); // Log.d("getJwkPublic key: ",pubkey.toString()); // Log.d("getJwkPublic jwk: ",jo.toString()); return jo.toString(); } catch (Exception e) { e.printStackTrace(); } return null; } static String encodeB64(byte[] bytes) { try { return Base64.encodeToString(bytes, Base64.URL_SAFE | Base64.NO_PADDING | Base64.NO_WRAP); } catch (Exception e) { } return null; } }