Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you 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. */ package org.apache.karaf.shell.ssh.keygenerator; import java.io.File; import java.io.FileNotFoundException; import java.io.FileOutputStream; import java.io.IOException; import java.security.KeyPair; import java.util.ArrayList; import java.util.Collection; import org.apache.commons.ssl.PEMItem; import org.apache.commons.ssl.PEMUtil; public class PemWriter { private File keyFile; public PemWriter(File keyFile) { this.keyFile = keyFile; } public void writeKeyPair(String resource, KeyPair kp) throws IOException, FileNotFoundException { Collection<Object> items = new ArrayList<>(); items.add(new PEMItem(kp.getPrivate().getEncoded(), "PRIVATE KEY")); byte[] bytes = PEMUtil.encode(items); try (FileOutputStream os = new FileOutputStream(keyFile)) { os.write(bytes); } } }