Java tutorial
/******************************************************************************* * Copyright (c) 2013-2015 Sierra Wireless and others. * * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * and Eclipse Distribution License v1.0 which accompany this distribution. * * The Eclipse Public License is available at * http://www.eclipse.org/legal/epl-v10.html * and the Eclipse Distribution License is available at * http://www.eclipse.org/org/documents/edl-v10.html. * * Contributors: * Sierra Wireless - initial API and implementation * Achim Kraus (Bosch Software Innovations GmbH) - add json as storage format *******************************************************************************/ package org.eclipse.leshan.server.bootstrap.demo; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.lang.reflect.Type; import java.util.Collections; import java.util.Map; import java.util.concurrent.ConcurrentHashMap; import org.eclipse.leshan.core.request.Identity; import org.eclipse.leshan.server.bootstrap.BootstrapConfig; import org.eclipse.leshan.server.bootstrap.BootstrapStore; import org.eclipse.leshan.server.bootstrap.demo.ConfigurationChecker.ConfigurationException; import org.eclipse.leshan.util.Validate; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.google.gson.Gson; import com.google.gson.GsonBuilder; import com.google.gson.reflect.TypeToken; /** * Simple bootstrap store implementation storing bootstrap information in memory */ public class BootstrapStoreImpl implements BootstrapStore { private static final Logger LOG = LoggerFactory.getLogger(BootstrapStoreImpl.class); // default location for persistence public static final String DEFAULT_FILE = "data/bootstrap.json"; private final String filename; private final Gson gson; private final Type gsonType; public BootstrapStoreImpl() { this(DEFAULT_FILE); } /** * @param filename the file path to persist the registry */ public BootstrapStoreImpl(String filename) { Validate.notEmpty(filename); GsonBuilder builder = new GsonBuilder(); builder.setPrettyPrinting(); this.gson = builder.create(); this.gsonType = new TypeToken<Map<String, BootstrapConfig>>() { }.getType(); this.filename = filename; this.loadFromFile(); } private Map<String, BootstrapConfig> bootstrapByEndpoint = new ConcurrentHashMap<>(); @Override public BootstrapConfig getBootstrap(String endpoint, Identity deviceIdentity) { return bootstrapByEndpoint.get(endpoint); } public void addConfig(String endpoint, BootstrapConfig config) throws ConfigurationException { ConfigurationChecker.verify(config); bootstrapByEndpoint.put(endpoint, config); saveToFile(); } public Map<String, BootstrapConfig> getBootstrapConfigs() { return Collections.unmodifiableMap(bootstrapByEndpoint); } public boolean deleteConfig(String enpoint) { BootstrapConfig res = bootstrapByEndpoint.remove(enpoint); saveToFile(); return res != null; } // /////// File persistence private void loadFromFile() { try { File file = new File(filename); if (file.exists()) { try (InputStreamReader in = new InputStreamReader(new FileInputStream(file))) { Map<String, BootstrapConfig> config = gson.fromJson(in, gsonType); bootstrapByEndpoint.putAll(config); } } } catch (Exception e) { LOG.error("Could not load bootstrap infos from file", e); } } private synchronized void saveToFile() { try { // Create file if it does not exists. File file = new File(filename); if (!file.exists()) { File parent = file.getParentFile(); if (parent != null) { parent.mkdirs(); } file.createNewFile(); } // Write file try (OutputStreamWriter out = new OutputStreamWriter(new FileOutputStream(filename))) { out.write(gson.toJson(getBootstrapConfigs(), gsonType)); } } catch (Exception e) { LOG.error("Could not save bootstrap infos to file", e); } } }