io.jbotsim.core.Link Maven / Gradle / Ivy
/*
* Copyright 2008 - 2019, Arnaud Casteigts and the JBotSim contributors
*
*
* This file is part of JBotSim.
*
* JBotSim is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* JBotSim is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with JBotSim. If not, see The {@link Link} object encodes a communication link between two {@link Node}s.
*
* Links can either be {@link Type#DIRECTED} or {@link Type#UNDIRECTED}, and either
* {@link Mode#WIRED} or {@link Mode#WIRELESS}.
* The by default, a link will be {@link Type#UNDIRECTED} and {@link Mode#WIRELESS}.
*/
public class Link extends Properties implements Comparable {
public static final Color DEFAULT_COLOR = Color.darkGray;
public static final int DEFAULT_WIDTH = 1;
public static final Type DEFAULT_TYPE = Type.UNDIRECTED;
public static final Mode DEFAULT_MODE = Mode.WIRED;
Integer width = DEFAULT_WIDTH;
Color color = DEFAULT_COLOR;
/**
* Enumerates the two possible types of a link: Type.DIRECTED and
* Type.UNDIRECTED.
*/
public enum Type {
DIRECTED, UNDIRECTED
}
/**
* Enumerates the two possible modes of a link: Mode.WIRED and
* Mode.WIRELESS.
*/
public enum Mode {
WIRED, WIRELESS
}
/**
* The source node of this link (if directed),
* the first endpoint otherwise.
*/
public Node source;
/**
* The destination node of this link (if directed),
* the second endpoint otherwise.
*/
public Node destination;
/**
* The Type of this link (directed/undirected)
*/
public Type type;
/**
* The Mode of this link (wired/wireless)
*/
public Mode mode;
/**
* Creates an undirected wired link between the two specified nodes.
*
* @param n1 The source node.
* @param n2 The destination node.
*/
public Link(Node n1, Node n2) {
this(n1, n2, DEFAULT_TYPE, DEFAULT_MODE);
}
/**
* Creates a wired link of the specified type between the nodes
* from and to. The respective order of from
* and to does not matter if the specified type is undirected.
*
* @param from The source node.
* @param to The destination node.
* @param type The type of the link (Type.DIRECTED or
* Type.UNDIRECTED).
*/
public Link(Node from, Node to, Type type) {
this(from, to, type, DEFAULT_MODE);
}
/**
* Creates a link with the specified mode between the nodes
* from and to. The created link is undirected by
* default. The respective order of from and to does not
* matter.
*
* @param from The source node.
* @param to The destination node.
* @param mode The mode of the link (Mode.WIRED or
* Mode.WIRELESS).
*/
public Link(Node from, Node to, Mode mode) {
this(from, to, DEFAULT_TYPE, mode);
}
/**
* Creates a link of the specified type with the specified
* mode between the nodes from and to. The created link is wired
* by default. The respective order of from and to does
* not matter if the type is undirected.
*
* @param from The source node.
* @param to The destination node.
* @param type The type of the link (Type.DIRECTED or
* Type.UNDIRECTED).
* @param mode The mode of the link (Mode.WIRED or
* Mode.WIRELESS).
*/
public Link(Node from, Node to, Type type, Mode mode) {
source = from;
destination = to;
this.type = type;
this.mode = mode;
}
/**
* Returns an list containing the two endpoint nodes of this link
*
* @return The endpoints.
*/
public List endpoints() {
List tmp = new ArrayList<>();
tmp.add(source);
tmp.add(destination);
return tmp;
}
/**
* Returns the requested endpoint node of this link
*
* @param index The endpoint index (0 or 1).
* @return The endpoint.
*/
public Node endpoint(int index) {
assert (index == 0 || index == 1);
return (index == 0) ? source : destination;
}
/**
* Returns the node located at the opposite of the specified node
* (reference node) on the underlying link.
*
* @param n The reference node.
* @return The opposite node.
*/
public Node getOtherEndpoint(Node n) {
return (n == source) ? destination : source;
}
/**
* Returns the parent topology of this link, if any.
*
* @return The parent topology, or null if the link has none.
*/
public Topology getTopology() {
return source.getTopology();
}
/**
* Returns the color of this link.
* @return the {@link Color} of the link.
*/
public Color getColor() {
return color;
}
/**
* Sets the color of this link
* @param color the new {@link Color} of the link.
*/
public void setColor(Color color) {
this.color = (color != null) ? color : Color.darkGray;
setProperty("color", color); // Used for property notification
}
/**
* Returns the width of this link.
* @return the width of this link.
*/
public Integer getWidth() {
return width;
}
/**
* Sets the width of this link.
* @param width the width of this link.
*/
public void setWidth(Integer width) {
this.width = width;
setProperty("width", width); // Used for property notification
}
/**
* Returns the euclidean distance between this link endpoints.
* @return the length between the endpoints, as a {@link Double}.
*/
public Double getLength() {
return source.distance(destination);
}
/**
* Tests whether the mode is WIRELESS.
* @return true if the link mode is WIRELESS,
* false otherwise.
*/
public boolean isWireless() {
return mode == Mode.WIRELESS;
}
/**
* Tests whether the type is DIRECTED.
* @return true if the link type is DIRECTED,
* false otherwise.
*/
public boolean isDirected() {
return type == Type.DIRECTED;
}
/**
* Compares the specified object with this link for equality. Returns
* true if both links have the same type
* (directed/undirected) and the same endpoints (interchangeably if
* undirected). The mode is not considered by the equality test.
*/
public boolean equals(Object o) {
Link l = (Link) o;
if (this.type != l.type)
return false;
else if (this.type == Type.DIRECTED)
return (l.source == this.source && l.destination == this.destination);
else
return (l.source == this.source && l.destination == this.destination) ||
(l.source == this.destination && l.destination == this.source);
}
/**
* Compares the specified link to this link in terms of length.
*/
public int compareTo(Link l) {
return getLength().compareTo(l.getLength());
}
/**
* Returns a string representation of this link.
*/
public String toString() {
if (type == Type.DIRECTED)
return (source + " --> " + destination);
else
return (source + " <--> " + destination);
}
}