2 * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.controller.md.sal.common.impl.routing;
10 import java.util.Map.Entry;
12 import org.opendaylight.controller.md.sal.common.api.data.DataReader;
13 import org.opendaylight.yangtools.concepts.AbstractObjectRegistration;
14 import org.opendaylight.yangtools.concepts.Path;
15 import org.opendaylight.yangtools.concepts.Registration;
17 import com.google.common.base.Function;
18 import com.google.common.base.Predicate;
19 import com.google.common.collect.FluentIterable;
20 import com.google.common.collect.HashMultimap;
21 import com.google.common.collect.Multimap;
24 * Base abstract implementation of DataReadRouter, which performs
25 * a read operation on multiple data readers and then merges result.
30 public abstract class AbstractDataReadRouter<P extends Path<P>, D> implements DataReader<P, D> {
32 Multimap<P, DataReaderRegistration<P, D>> configReaders = HashMultimap.create();
33 Multimap<P, DataReaderRegistration<P, D>> operationalReaders = HashMultimap.create();
36 public D readConfigurationData(P path) {
37 FluentIterable<D> dataBits = FluentIterable //
38 .from(getReaders(configReaders, path)).transform(configurationRead(path));
39 return merge(path,dataBits);
43 public D readOperationalData(P path) {
44 FluentIterable<D> dataBits = FluentIterable //
45 .from(getReaders(operationalReaders, path)).transform(operationalRead(path));
46 return merge(path,dataBits);
51 * Merges data readed by reader instances from specified path
53 * @param path Path on which read was performed
54 * @param data Data which was returned by read operation.
55 * @return Merged result.
57 protected abstract D merge(P path,Iterable<D> data);
60 * Returns a function which performs configuration read for supplied path
63 * @return function which performs configuration read for supplied path
66 private Function<DataReader<P, D>, D> configurationRead(final P path) {
67 return new Function<DataReader<P, D>, D>() {
69 public D apply(DataReader<P, D> input) {
70 return input.readConfigurationData(path);
76 * Returns a function which performs operational read for supplied path
79 * @return function which performs operational read for supplied path
81 private Function<DataReader<P, D>, D> operationalRead(final P path) {
82 return new Function<DataReader<P, D>, D>() {
84 public D apply(DataReader<P, D> input) {
85 return input.readOperationalData(path);
93 * Register's a reader for operational data.
95 * @param path Path which is served by this reader
96 * @param reader Reader instance which is responsible for reading particular subpath.
99 public Registration<DataReader<P, D>> registerOperationalReader(P path, DataReader<P, D> reader) {
100 OperationalDataReaderRegistration<P, D> ret = new OperationalDataReaderRegistration<>(path, reader);
101 operationalReaders.put(path, ret);
105 public Registration<DataReader<P, D>> registerConfigurationReader(P path, DataReader<P, D> reader) {
106 ConfigurationDataReaderRegistration<P, D> ret = new ConfigurationDataReaderRegistration<>(path, reader);
107 configReaders.put(path, ret);
111 Iterable<DataReader<P, D>> getOperationalReaders(P path) {
112 return getReaders(operationalReaders, path);
115 Iterable<DataReader<P, D>> getConfigurationReaders(P path) {
116 return getReaders(configReaders, path);
119 private Iterable<DataReader<P, D>> getReaders(Multimap<P, DataReaderRegistration<P, D>> readerMap, P path) {
120 return FluentIterable
121 .from(readerMap.entries()) //
122 .filter(affects(path)) //
123 .transform(retrieveInstance());
126 private void removeRegistration(OperationalDataReaderRegistration<?, ?> registration) {
127 operationalReaders.remove(registration.getKey(), registration);
130 private void removeRegistration(ConfigurationDataReaderRegistration<?, ?> registration) {
131 configReaders.remove(registration.getKey(), registration);
134 private Function<? super Entry<P, DataReaderRegistration<P, D>>, DataReader<P, D>> retrieveInstance() {
135 return new Function<Entry<P, DataReaderRegistration<P, D>>, DataReader<P,D>>() {
137 public DataReader<P, D> apply(Entry<P, DataReaderRegistration<P, D>> input) {
138 return input.getValue().getInstance();
143 private Predicate<? super Entry<P, DataReaderRegistration<P, D>>> affects(final P path) {
145 return new Predicate<Entry<P, DataReaderRegistration<P, D>>>() {
148 public boolean apply(Entry<P, DataReaderRegistration<P, D>> input) {
149 final P key = input.getKey();
150 return key.contains(path) || ((P) path).contains(key);
156 @SuppressWarnings("hiding")
157 private class ConfigurationDataReaderRegistration<P extends Path<P>, D> extends DataReaderRegistration<P, D> {
159 public ConfigurationDataReaderRegistration(P key, DataReader<P, D> instance) {
160 super(key, instance);
164 protected void removeRegistration() {
165 AbstractDataReadRouter.this.removeRegistration(this);
169 @SuppressWarnings("hiding")
170 private class OperationalDataReaderRegistration<P extends Path<P>, D> extends DataReaderRegistration<P, D> {
172 public OperationalDataReaderRegistration(P key, DataReader<P, D> instance) {
173 super(key, instance);
177 protected void removeRegistration() {
178 AbstractDataReadRouter.this.removeRegistration(this);
182 private abstract static class DataReaderRegistration<P extends Path<P>, D> extends
183 AbstractObjectRegistration<DataReader<P, D>> {
191 public DataReaderRegistration(P key, DataReader<P, D> instance) {