| /* |
| * 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.bookkeeper.net; |
| |
| /** |
| * A base class that implements interface Node. |
| */ |
| public class NodeBase implements Node { |
| /** |
| * Path separator {@value}. |
| */ |
| public static final char PATH_SEPARATOR = '/'; |
| /** |
| * Path separator as a string {@value}. |
| */ |
| public static final String PATH_SEPARATOR_STR = "/"; |
| /** |
| * String representation of root {@value}. |
| */ |
| public static final String ROOT = ""; |
| |
| protected String name; //host:port# |
| protected String location; //string representation of this node's location |
| protected int level; //which level of the tree the node resides |
| protected Node parent; //its parent |
| |
| /** |
| * Default constructor. |
| */ |
| public NodeBase() { |
| } |
| |
| /** |
| * Construct a node from its path. |
| * @param path |
| * a concatenation of this node's location, the path seperator, and its name |
| */ |
| public NodeBase(String path) { |
| path = normalize(path); |
| int index = path.lastIndexOf(PATH_SEPARATOR); |
| if (index == -1) { |
| set(ROOT, path); |
| } else { |
| set(path.substring(index + 1), path.substring(0, index)); |
| } |
| } |
| |
| /** |
| * Construct a node from its name and its location. |
| * @param name this node's name (can be null, must not contain {@link #PATH_SEPARATOR}) |
| * @param location this node's location |
| */ |
| public NodeBase(String name, String location) { |
| set(name, normalize(location)); |
| } |
| |
| /** |
| * Construct a node from its name and its location. |
| * @param name this node's name (can be null, must not contain {@link #PATH_SEPARATOR}) |
| * @param location this node's location |
| * @param parent this node's parent node |
| * @param level this node's level in the tree |
| */ |
| public NodeBase(String name, String location, Node parent, int level) { |
| set(name, normalize(location)); |
| this.parent = parent; |
| this.level = level; |
| } |
| |
| /** |
| * Set this node's name and location. |
| * @param name the (nullable) name -which cannot contain the {@link #PATH_SEPARATOR} |
| * @param location the location |
| */ |
| private void set(String name, String location) { |
| if (name != null && name.contains(PATH_SEPARATOR_STR)) { |
| throw new IllegalArgumentException("Network location name contains /: " + name); |
| } |
| this.name = (name == null) ? "" : name; |
| this.location = location; |
| } |
| |
| /** @return this node's name */ |
| @Override |
| public String getName() { |
| return name; |
| } |
| |
| /** @return this node's network location */ |
| @Override |
| public String getNetworkLocation() { |
| return location; |
| } |
| |
| /** |
| * Set this node's network location. |
| * @param location the location |
| */ |
| @Override |
| public void setNetworkLocation(String location) { |
| this.location = location; |
| } |
| |
| /** |
| * Get the path of a node. |
| * @param node a non-null node |
| * @return the path of a node |
| */ |
| public static String getPath(Node node) { |
| return node.getNetworkLocation() + PATH_SEPARATOR_STR + node.getName(); |
| } |
| |
| /** @return this node's path as its string representation */ |
| @Override |
| public String toString() { |
| return getPath(this); |
| } |
| |
| /** |
| * Normalize a path by stripping off any trailing {@link #PATH_SEPARATOR}. |
| * @param path path to normalize. |
| * @return the normalised path |
| * If <i>path</i>is null or empty {@link #ROOT} is returned |
| * @throws IllegalArgumentException if the first character of a non empty path |
| * is not {@link #PATH_SEPARATOR} |
| */ |
| public static String normalize(String path) { |
| if (path == null || path.length() == 0) { |
| return ROOT; |
| } |
| |
| if (path.charAt(0) != PATH_SEPARATOR) { |
| throw new IllegalArgumentException("Network Location path does not start with " + PATH_SEPARATOR_STR + ": " |
| + path); |
| } |
| |
| int len = path.length(); |
| if (path.charAt(len - 1) == PATH_SEPARATOR) { |
| return path.substring(0, len - 1); |
| } |
| return path; |
| } |
| |
| /** @return this node's parent */ |
| @Override |
| public Node getParent() { |
| return parent; |
| } |
| |
| /** |
| * Set this node's parent. |
| * @param parent the parent |
| */ |
| @Override |
| public void setParent(Node parent) { |
| this.parent = parent; |
| } |
| |
| /** @return this node's level in the tree. |
| * E.g. the root of a tree returns 0 and its children return 1 |
| */ |
| @Override |
| public int getLevel() { |
| return level; |
| } |
| |
| /** |
| * Set this node's level in the tree. |
| * @param level the level |
| */ |
| @Override |
| public void setLevel(int level) { |
| this.level = level; |
| } |
| |
| public static int locationToDepth(String location) { |
| String normalizedLocation = normalize(location); |
| int length = normalizedLocation.length(); |
| int depth = 0; |
| for (int i = 0; i < length; i++) { |
| if (normalizedLocation.charAt(i) == PATH_SEPARATOR) { |
| depth++; |
| } |
| } |
| return depth; |
| } |
| |
| @Override |
| public String getNetworkLocation(int distanceFromLeaves) { |
| Node node = this; |
| while (distanceFromLeaves > 1) { |
| Node parent = node.getParent(); |
| if (null == parent) { |
| break; |
| } |
| node = parent; |
| distanceFromLeaves--; |
| } |
| return node.getNetworkLocation(); |
| } |
| } |