| /* |
| * Copyright 2015 Open Networking Laboratory |
| * |
| * 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. |
| */ |
| package org.onosproject.net.driver; |
| |
| import com.google.common.collect.ImmutableMap; |
| import com.google.common.collect.Maps; |
| import org.apache.commons.configuration.ConfigurationException; |
| import org.apache.commons.configuration.HierarchicalConfiguration; |
| import org.apache.commons.configuration.XMLConfiguration; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.util.Map; |
| |
| /** |
| * Utility capable of reading driver configuration XML resources and producing |
| * a device driver provider as a result. |
| * <p> |
| * The drivers stream structure is as follows: |
| * </p> |
| * <pre> |
| * <drivers> |
| * <driver name=“...” [manufacturer="..." hwVersion="..." swVersion="..."]> |
| * <behaviour api="..." impl="..."/> |
| * ... |
| * [<property name=“key”>value</key>] |
| * ... |
| * </driver> |
| * ... |
| * </drivers> |
| * </pre> |
| */ |
| public class XmlDriverLoader { |
| |
| private static final String DRIVERS = "drivers"; |
| private static final String DRIVER = "driver"; |
| |
| private static final String BEHAVIOUR = "behaviour"; |
| private static final String PROPERTY = "property"; |
| |
| private static final String NAME = "[@name]"; |
| private static final String EXTENDS = "[@extends]"; |
| private static final String MFG = "[@manufacturer]"; |
| private static final String HW = "[@hwVersion]"; |
| private static final String SW = "[@swVersion]"; |
| private static final String API = "[@api]"; |
| private static final String IMPL = "[@impl]"; |
| |
| private final ClassLoader classLoader; |
| |
| private Map<String, Driver> drivers = Maps.newHashMap(); |
| |
| /** |
| * Creates a new driver loader capable of loading drivers from the supplied |
| * class loader. |
| * |
| * @param classLoader class loader to use |
| */ |
| public XmlDriverLoader(ClassLoader classLoader) { |
| this.classLoader = classLoader; |
| } |
| |
| /** |
| * Loads the specified drivers resource as an XML stream and parses it to |
| * produce a ready-to-register driver provider. |
| * |
| * @param driversStream stream containing the drivers definitions |
| * @param resolver driver resolver |
| * @return driver provider |
| * @throws java.io.IOException if issues are encountered reading the stream |
| * or parsing the driver definitions within |
| */ |
| public DefaultDriverProvider loadDrivers(InputStream driversStream, |
| DriverResolver resolver) throws IOException { |
| try { |
| XMLConfiguration cfg = new XMLConfiguration(); |
| cfg.setRootElementName(DRIVERS); |
| cfg.setAttributeSplittingDisabled(true); |
| |
| cfg.load(driversStream); |
| return loadDrivers(cfg, resolver); |
| } catch (ConfigurationException e) { |
| throw new IOException("Unable to load drivers", e); |
| } |
| } |
| |
| /** |
| * Loads a driver provider from the supplied hierarchical configuration. |
| * |
| * @param driversCfg hierarchical configuration containing the drivers definitions |
| * @param resolver driver resolver |
| * @return driver provider |
| */ |
| public DefaultDriverProvider loadDrivers(HierarchicalConfiguration driversCfg, |
| DriverResolver resolver) { |
| DefaultDriverProvider provider = new DefaultDriverProvider(); |
| for (HierarchicalConfiguration cfg : driversCfg.configurationsAt(DRIVER)) { |
| DefaultDriver driver = loadDriver(cfg, resolver); |
| drivers.put(driver.name(), driver); |
| provider.addDriver(driver); |
| } |
| drivers.clear(); |
| return provider; |
| } |
| |
| /** |
| * Loads a driver from the supplied hierarchical configuration. |
| * |
| * @param driverCfg hierarchical configuration containing the driver definition |
| * @param resolver driver resolver |
| * @return driver |
| */ |
| public DefaultDriver loadDriver(HierarchicalConfiguration driverCfg, |
| DriverResolver resolver) { |
| String name = driverCfg.getString(NAME); |
| String parentName = driverCfg.getString(EXTENDS); |
| String manufacturer = driverCfg.getString(MFG, ""); |
| String hwVersion = driverCfg.getString(HW, ""); |
| String swVersion = driverCfg.getString(SW, ""); |
| |
| Driver parent = parentName != null ? resolve(parentName, resolver) : null; |
| return new DefaultDriver(name, parent, manufacturer, hwVersion, swVersion, |
| parseBehaviours(driverCfg), |
| parseProperties(driverCfg)); |
| } |
| |
| // Resolves the driver by name locally at first and then using the specified resolver. |
| private Driver resolve(String parentName, DriverResolver resolver) { |
| Driver driver = drivers.get(parentName); |
| return driver != null ? driver : |
| (resolver != null ? resolver.getDriver(parentName) : null); |
| } |
| |
| // Parses the behaviours section. |
| private Map<Class<? extends Behaviour>, Class<? extends Behaviour>> |
| parseBehaviours(HierarchicalConfiguration driverCfg) { |
| ImmutableMap.Builder<Class<? extends Behaviour>, |
| Class<? extends Behaviour>> behaviours = ImmutableMap.builder(); |
| for (HierarchicalConfiguration b : driverCfg.configurationsAt(BEHAVIOUR)) { |
| behaviours.put(getClass(b.getString(API)), getClass(b.getString(IMPL))); |
| } |
| return behaviours.build(); |
| } |
| |
| // Parses the properties section. |
| private Map<String, String> parseProperties(HierarchicalConfiguration driverCfg) { |
| ImmutableMap.Builder<String, String> properties = ImmutableMap.builder(); |
| for (HierarchicalConfiguration b : driverCfg.configurationsAt(PROPERTY)) { |
| properties.put(b.getString(NAME), (String) b.getRootNode().getValue()); |
| } |
| return properties.build(); |
| } |
| |
| @SuppressWarnings("unchecked") |
| private Class<? extends Behaviour> getClass(String className) { |
| try { |
| return (Class<? extends Behaviour>) classLoader.loadClass(className); |
| } catch (ClassNotFoundException e) { |
| throw new IllegalArgumentException("Unable to load class " + className, e); |
| } |
| } |
| |
| } |