我编写了一个程序，允许用户添加节点并使用GUI界面连接边缘。第一个节点始终标记为＆＃34; 0＆＃34;。当我调用findPath方法但是它只显示缺少0的整个路径。例如，如果我想找到0-4的路径，并且它们全部以数字方式连接，则显示[1,2,3] ，4]。要在连接节点后正确读取路径，您需要点击打印邻接按钮。其他所有东西都按预期运行，但我似乎无法弄清楚为什么这不会添加第一个节点。
谢谢大家！
import javax.swing.JFrame;//imports JFrame package
public class Graph//class header
{
public static void main (String[] args)//main method
{
JFrame frame = new JFrame ("Directed Graph");//sets variable frame to a JFrame object and titles it
frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE);//exits application when it is closed
frame.getContentPane().add (new GraphPanel());//adding GraphPanel() to the frame
frame.setLocationRelativeTo(null);//sets location to the center
frame.pack();//packs the frame, fits everything inside
frame.setVisible(true);//makes frame visible
}
}
import java.util.ArrayList;//all of these are the required to get classes from other packages
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JPanel;
public class GraphPanel extends JPanel
{
private final int SIZE = 10; // radius of each node
private double alpha; // double variable to define later
private JButton print, create, delete, path1; //allpath;//button variables
private JTextField label, label1;
boolean mode = true;//sets boolean for entire class to true, until later when I define it as false for certain methods to be complete
String x1, y1;
String str1 = new String("Mode Chosen Is : create" );//when you choose create it will print this instead
String str2 = new String("Mode Chosen Is : delete" );//when you choose delete it will print this
int x, y;
int mode1 = 1; // int mode1 variable, will comment why i need this when it is later defined/changed
private Point point1 = null, point2 = null, point3 = null;//makes pointers null, i added a third pointer to put the distance from the first drawn string at the top right, but no longer needed it
//keeping it incase I wanted to add it again
private ArrayList<Point> nodeList; // Graph nodes
private ArrayList<Edge> edgeList; // Graph edges
static private int[][] a = new int[100][100]; // Graph adjacency matrix
static ArrayList<Integer> path = new ArrayList<Integer>();
public GraphPanel()
{
nodeList = new ArrayList<Point>();//declares ArrayList<Point>
edgeList = new ArrayList<Edge>();//declares ArrayList<Edge>
GraphListener listener = new GraphListener();//assigns 'listener' to a Graphlistener object
addMouseListener (listener);//accepts and reads mouseListener methods to the GraphListener object
addMouseMotionListener (listener);//accepts and reads MouseMotionListener methods to the GraphListener object
label = new JTextField (1);
label1 = new JTextField (1);
//allpath = new JButton ("Find All Paths");
path1 = new JButton ("Find Path");//path button
create = new JButton("Create");//declares 'create' as a JButton object with text on it that says 'create'
delete = new JButton("Delete");//declares 'delete' as a JButton object with text that says 'delete'
JButton print = new JButton("Print adjacency matrix");//declares 'print' as a JButton object with text that reads 'print adjacency matrix'
print.addActionListener (new ButtonListener());//adds an action listener to the print button from the buttonlistener object
create.addActionListener (new ButtonListener1());//adds an actionListener to the create button from the buttonlistener1 object
delete.addActionListener (new ButtonListener2());//adds an actionliseneer to the delete button from the buttonlistener2 object
path1.addActionListener (new ButtonListener3());//adds button that will find path of nodes
//allpath.addActionListener (new ButtonListener4());
setBackground (Color.black);//sets backround as black
setPreferredSize (new Dimension(400, 300));//this is preferred size of graphpanel
add(print);//these next six add()'s add each button to GraphPanel
add(delete);//
add(create);//
//add(allpath);
add(path1);
add(label);
add(label1);
}
public static boolean findPath(int x, int y) //boolean method findpath that takes two ints as parameters
{
boolean found = false;
if (a[x][y]==1) //base case
{
//System.out.println(x + " -> " + y);//prints node -> node
found = true;//path is found
path.add(0,y);
}
else
{
int z;
for (z=0; !found& z<a.length; z++)
{
if (a[x][z]==1)
{
a[x][z]=2;
found = findPath(z,y);
}
if (found)
{
//System.out.println(x + " -> " + z);
path.add(0,z);
}
}
}
if (!found){
System.out.println("Path Does Not Exist");
}
return found;
}
// public static ArrayList findPath1(int x, int y, ArrayList path)
// {
// System.out.println("CALL FIND: " + path);
// ArrayList path2 = null;
// if (a[x][y]==1)
// {
// ArrayList path3 = (ArrayList)path.clone();
// path3.add(y);
// System.out.println("EXIT BASE: " + path3);
// path2 = path3;
// }
// else
// {
// int z;
// for (z=0; z<a.length; z++)
// if (a[x][z]==1)
// {
// ArrayList path3 = (ArrayList)path.clone();
// path3.add(z);
// path3 = findPath1(z,y,path3);
// System.out.println("EXIT RECU: " + path);
// path2 = path3;
// }
// }
// return path2;
// }
// Draws the graph
public void paintComponent (Graphics page)
{
super.paintComponent(page);//using parent methods
// Draws the edge that is being dragged
page.setColor (Color.green);//setting color of what will be drawn to green
if (mode1 == 1)//if mode1 is set to 1, which is when the create button is selected
{
page.drawString(str1, 125, 75);//then this is printed
}
if (mode1 == 2)//if mode1 is set to 2, which is when the delete button is selected
{
page.drawString(str2, 125, 75);//then this is printed
}
if (point1 != null && point2 != null)//if and only if both points are not null
{
page.drawLine (point1.x, point1.y, point2.x, point2.y);//then it draws the line from between point1(x, y cords), and point2(x, y cords)
page.fillOval (point2.x-3, point2.y-3, 6, 6);//fills this oval by the rectangle it is specified from
}
// Draws the nodes
for (int i=0; i<nodeList.size(); i++) //for loop going through the nodeList ArrayList
{
page.setColor (Color.green);//color is set to green
page.fillOval (nodeList.get(i).x-SIZE, nodeList.get(i).y-SIZE, SIZE*2, SIZE*2);//fills oval by subtracting the SIZE from the x, y and setting the height and width as two times the SIZE
page.setColor (Color.black);//sets next line to black
page.drawString (String.valueOf(i), nodeList.get(i).x-SIZE/2, nodeList.get(i).y+SIZE/2);//writes inside the node what number index it is from the ArrayList with black text
}
// Draws the edges
for (int i=0; i<edgeList.size(); i++) // for loop going through the edgeList ArrayList
{
page.setColor (Color.green);//sets the next line to green
page.drawLine (edgeList.get(i).a.x, edgeList.get(i).a.y,edgeList.get(i).b.x, edgeList.get(i).b.y);//draws the line from x and y cords of where it starts to end
//page.fillOval (edgeList.get(i).b.x-3, edgeList.get(i).b.y-3, 6, 6);
//page.drawString (String.valueOf(point1.x*(point2.y-point3.y)+point2.x*(point3.y-point1.y)+point3.x*(point1.y-point2.y)), 5, 15);
alpha = Math.atan((double)(edgeList.get(i).b.y-edgeList.get(i).a.y)/(edgeList.get(i).b.x-edgeList.get(i).a.x));//alpha = b.y-a.y cords/b.x-a.x chords as a double variable
if (edgeList.get(i).a.x > edgeList.get(i).b.x)//if the x chord of a is greater than the x cordinate of b
{
alpha = alpha + Math.PI;//then alpha = previously defined alpha multiplied by PI
}
if (edgeList.get(i).a.x < edgeList.get(i).b.x && edgeList.get(i).a.y > edgeList.get(i).b.y)//if a.x is less than b.x and a.y is less than b.y
{
alpha = alpha + 2*Math.PI;//then alpha becomes the previously defined alpha multiplied by 2 PI
}
arrow(page,edgeList.get(i).b.x,edgeList.get(i).b.y,0,1.57-alpha);//arrow method, taking a x(edgeList.get(i).b.x, y(edgeList.get(i).b.y, length = 0 so arrow is at the
// very end of the drawn line subtracted by a double aplha
}
}
// arrow method to call when making an arrow
private void arrow(Graphics page, int x, int y, int len, double alpha)//arrow method, taking a x, y, length and double parameter
{
page.setColor (Color.green);//sets arrow to green
int x1 = x+(int)(len*Math.sin(alpha));//x1 is set to x plus length *sin of alpha
int y1 = y+(int)(len*Math.cos(alpha));//y1 is set to y plus the length * cosin of alpha
page.drawLine (x, y, x1, y1);//drawa the x and y, and then previously defined x1, and y1
page.drawLine (x1, y1, x1+(int)(20*Math.sin(alpha+2.5)), y1+(int)(20*Math.cos(alpha+2.5)));//arithmatic to draw one side of the line for the arrow
page.drawLine (x1, y1, x1+(int)(20*Math.sin(alpha+3.7)), y1+(int)(20*Math.cos(alpha+3.7)));//arithmatic to draw the corresponding line for the arrow to complete the arrow
}
// The listener for mouse events.
private class GraphListener implements MouseListener, MouseMotionListener//GraphListener which implements MouseListener and MouseMotionListener, meaning it takes methods from both of those classes
{
public void mouseClicked (MouseEvent event)//when mouse is clicked and released
{
if (mode == true)//if the mode is true
{
nodeList.add(event.getPoint());//the current point to the nodeList
repaint();//whenever you change the look of a componenet you call this method
}
if (mode == false)//if boolean mode is false
{
for (int i=0; i<nodeList.size(); i++)//for loop to go through the nodeList ArrayList
{
if (distance(nodeList.get(i), event.getPoint()) < SIZE)//if the distance between a specific node and the pointer is less than the radius of the node (SIZE)
nodeList.remove(i);//then remove that node
}
for (int i=0; i<edgeList.size(); i++)
{
if (distance(edgeList.get(i).a, event.getPoint())+distance(event.getPoint(), edgeList.get(i).b)-distance(edgeList.get(i).a, edgeList.get(i).b) < SIZE)
//if the (distance between starting point of that edgelist index and the current point) plus (the distance between the current point and ending point of that edgeList index)
//subtracted by the (distance of the starting and ending point of that edgeList index)(AB+BC-AC) is all less than the size
edgeList.remove(i);//then remove that index
}
}
}
public void mousePressed (MouseEvent event)//when the mouse is pressed down
{
if (mode == true)//if the mode is true
{
point1 = event.getPoint();//you start that point
}
}
public void mouseDragged (MouseEvent event)//when the mouse is dragged while pressed down
{
if (mode == true)//if the mode is true
{
point2 = event.getPoint();//then you get the second point
repaint();//must use this method because you are making a change to the component
}
}
public void mouseReleased (MouseEvent event)//when the mouse is released after being pressed (not to be confused with a click)
{
if (mode == true)//if the mode is true
{
point2 = event.getPoint();//then you set point2 to where that point landed
if (point1.x != point2.x && point1.y != point2.y)//if the points are not in the same spots
{
edgeList.add(new Edge(point1,point2));//then you add a new edgeList element to the ArrayList, by definition of Edge() object
repaint();//must use this method because changes to component have been made
}
}
}
public void mouseMoved (MouseEvent event)// if the mouse is moved, without it being clicked (not to be confused by mouseDragged)
{
point3 = event.getPoint();//point three is set to be where the mouse is at the current time(used this to find the distance of original edge drawn, keeping here incase I want to add)
repaint();//must use this method because changes were made to component
}
// Empty definitions for unused event methods.
public void mouseEntered (MouseEvent event){}//when the mouse enters a component
public void mouseExited (MouseEvent event) {}//when the mouse exits a component
private int distance(Point p1, Point p2) //private distance formula but inside of this class so i was able to use it for determining how to erase nodes and edges
{
return (int)Math.sqrt((p1.x-p2.x)*(p1.x-p2.x)+(p1.y-p2.y)*(p1.y-p2.y));//square root of x cordinants of first point minus second point times its self plus the y coordinates
//of first point minus second point times itself
}
}
// Represents the graph edges
private class Edge //defines how edges are made
{
Point a, b;
public Edge(Point a, Point b)
{
this.a = a;
this.b = b;
}
}
private class ButtonListener implements ActionListener
{
public void actionPerformed (ActionEvent event)
{
if (event.getSource()== create)
{
mode = true;
mode1 = 1;
}
if (event.getSource()==delete)
{
mode = !true;
mode1 = 2;
}
// Initializes graph adjacency matrix
for (int i=0; i<nodeList.size(); i++)
for (int j=0; j<nodeList.size(); j++) a[i][j]=0;
// Includes the edges in the graph adjacency matrix
for (int i=0; i<edgeList.size(); i++)
{
for (int j=0; j<nodeList.size(); j++)
if (distance(nodeList.get(j),edgeList.get(i).a)<=SIZE+3)
for (int k=0; k<nodeList.size(); k++)
if (distance(nodeList.get(k),edgeList.get(i).b)<=SIZE+3)
{
System.out.println(j+"->"+k);
a[j][k]=1;
}
}
if (event.getSource()==print)
{
// Prints the graph adjacency matrix
for (int i=0; i<nodeList.size(); i++)
{
for (int j=0; j<nodeList.size(); j++)
System.out.print(a[i][j]+"\t");
System.out.println();
}
}
}
// Euclidean distance function
private int distance(Point p1, Point p2)
{
return (int)Math.sqrt((p1.x-p2.x)*(p1.x-p2.x)+(p1.y-p2.y)*(p1.y-p2.y));
}
}
private class ButtonListener1 implements ActionListener
{
public void actionPerformed (ActionEvent event)
{
if (event.getSource()== create)//if create button is selected
{
mode = true;//then the mode is set to true
mode1 = 1;//and mode1 is set to 1
}
}
}
private class ButtonListener2 implements ActionListener
{
public void actionPerformed (ActionEvent event)
{
if (event.getSource()== delete)//if create button is selected
{
mode = !true;//then the mode is set to true
mode1 = 2;//and mode1 is set to 2, which would change the string that is output
}
}
}
private class ButtonListener3 implements ActionListener
{
public void actionPerformed (ActionEvent event)
{
x1 = label.getText();
y1 = label1.getText();
x = Integer.parseInt(x1);
y = Integer.parseInt(y1);
System.out.println("Path from " +x+" to " +y);
System.out.println(findPath(x,y));
System.out.println(path);
}
}
答案 0 :(得分：0)
您永远不会将第一个节点添加到路径中。检查路径是否存在时，可以执行此操作：
if (!found){
System.out.println("Path Does Not Exist");
} else {
path.add(0, x);
}
然后你还需要删除这个块：
if (found) {
//System.out.println(x + " -> " + z);
path.add(0,z);
}
所以完整的方法看起来像
public static boolean findPath(int x, int y) //boolean method findpath that takes two ints as parameters
{
boolean found = false;
if (a[x][y]==1) //base case
{
//System.out.println(x + " -> " + y);//prints node -> node
found = true;//path is found
path.add(0,y);
}
else
{
int z;
for (z=0; !found& z<a.length; z++)
{
if (a[x][z]==1)
{
a[x][z]=2;
found = findPath(z,y);
}
/*if (found)
{
//System.out.println(x + " -> " + z);
path.add(0,z);
}*/
}
}
if (!found){
System.out.println("Path Does Not Exist");
} else {
path.add(0,x);
}
return found;
}
我还建议您查看Dijkstra's algorithm找到节点之间的最短路径
答案 1 :(得分：0)
我能够找到它，当然这是我错过的最小的错误，添加这个因为如果其他人有同样的问题，我希望这会有所帮助。主要区别在于我的buttonlistener3类，但我会再次添加整个内容，只是这可以帮助任何人。
import java.util.ArrayList;//all of these are the required to get classes from other packages
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.JPanel;
public class GraphPanel extends JPanel
{
private final int SIZE = 10; // radius of each node
private double alpha; // double variable to define later
private JButton print, create, delete, path1; //allpath;//button variables
private JTextField label, label1;
boolean mode = true;//sets boolean for entire class to true, until later when I define it as false for certain methods to be complete
String x1, y1;
String str1 = new String("Mode Chosen Is : create" );//when you choose create it will print this instead
String str2 = new String("Mode Chosen Is : delete" );//when you choose delete it will print this
int x, y;
int mode1 = 1; // int mode1 variable, will comment why i need this when it is later defined/changed
private Point point1 = null, point2 = null, point3 = null;//makes pointers null, i added a third pointer to put the distance from the first drawn string at the top right, but no longer needed it
//keeping it incase I wanted to add it again
private ArrayList<Point> nodeList; // Graph nodes
private ArrayList<Edge> edgeList; // Graph edges
static private int[][] a = new int[100][100]; // Graph adjacency matrix
static ArrayList<Integer> path = new ArrayList<Integer>();
public GraphPanel()
{
nodeList = new ArrayList<Point>();//declares ArrayList<Point>
edgeList = new ArrayList<Edge>();//declares ArrayList<Edge>
GraphListener listener = new GraphListener();//assigns 'listener' to a Graphlistener object
addMouseListener (listener);//accepts and reads mouseListener methods to the GraphListener object
addMouseMotionListener (listener);//accepts and reads MouseMotionListener methods to the GraphListener object
label = new JTextField (1);
label1 = new JTextField (1);
//allpath = new JButton ("Find All Paths");
path1 = new JButton ("Find Path");//path button
create = new JButton("Create");//declares 'create' as a JButton object with text on it that says 'create'
delete = new JButton("Delete");//declares 'delete' as a JButton object with text that says 'delete'
JButton print = new JButton("Print adjacency matrix");//declares 'print' as a JButton object with text that reads 'print adjacency matrix'
print.addActionListener (new ButtonListener());//adds an action listener to the print button from the buttonlistener object
create.addActionListener (new ButtonListener1());//adds an actionListener to the create button from the buttonlistener1 object
delete.addActionListener (new ButtonListener2());//adds an actionliseneer to the delete button from the buttonlistener2 object
path1.addActionListener (new ButtonListener3());//adds button that will find path of nodes
//allpath.addActionListener (new ButtonListener4());
setBackground (Color.black);//sets backround as black
setPreferredSize (new Dimension(400, 300));//this is preferred size of graphpanel
add(print);//these next six add()'s add each button to GraphPanel
add(delete);//
add(create);//
//add(allpath);
add(path1);
add(label);
add(label1);
}
public static boolean findPath(int x, int y) //boolean method findpath that takes two ints as parameters
{
boolean found = false;
if (a[x][y]==1) //base case
{
//System.out.println(x + " -> " + y);//prints node -> node
found = true;//path is found
path.add(0,y);
}
else
{
int z;
for (z=0; !found& z<a.length; z++)
{
if (a[x][z]==1)
{
a[x][z]=2;
found = findPath(z,y);
}
if (found)
{
//System.out.println(x + " -> " + z);
path.add(0,z);
}
}
}
return found;
}
// public static ArrayList findPath1(int x, int y, ArrayList path)
// {
// System.out.println("CALL FIND: " + path);
// ArrayList path2 = null;
// if (a[x][y]==1)
// {
// ArrayList path3 = (ArrayList)path.clone();
// path3.add(y);
// System.out.println("EXIT BASE: " + path3);
// path2 = path3;
// }
// else
// {
// int z;
// for (z=0; z<a.length; z++)
// if (a[x][z]==1)
// {
// ArrayList path3 = (ArrayList)path.clone();
// path3.add(z);
// path3 = findPath1(z,y,path3);
// System.out.println("EXIT RECU: " + path);
// path2 = path3;
// }
// }
// return path2;
// }
// Draws the graph
public void paintComponent (Graphics page)
{
super.paintComponent(page);//using parent methods
// Draws the edge that is being dragged
page.setColor (Color.green);//setting color of what will be drawn to green
if (mode1 == 1)//if mode1 is set to 1, which is when the create button is selected
{
page.drawString(str1, 125, 75);//then this is printed
}
if (mode1 == 2)//if mode1 is set to 2, which is when the delete button is selected
{
page.drawString(str2, 125, 75);//then this is printed
}
if (point1 != null && point2 != null)//if and only if both points are not null
{
page.drawLine (point1.x, point1.y, point2.x, point2.y);//then it draws the line from between point1(x, y cords), and point2(x, y cords)
page.fillOval (point2.x-3, point2.y-3, 6, 6);//fills this oval by the rectangle it is specified from
}
// Draws the nodes
for (int i=0; i<nodeList.size(); i++) //for loop going through the nodeList ArrayList
{
page.setColor (Color.green);//color is set to green
page.fillOval (nodeList.get(i).x-SIZE, nodeList.get(i).y-SIZE, SIZE*2, SIZE*2);//fills oval by subtracting the SIZE from the x, y and setting the height and width as two times the SIZE
page.setColor (Color.black);//sets next line to black
page.drawString (String.valueOf(i), nodeList.get(i).x-SIZE/2, nodeList.get(i).y+SIZE/2);//writes inside the node what number index it is from the ArrayList with black text
}
// Draws the edges
for (int i=0; i<edgeList.size(); i++) // for loop going through the edgeList ArrayList
{
page.setColor (Color.green);//sets the next line to green
page.drawLine (edgeList.get(i).a.x, edgeList.get(i).a.y,edgeList.get(i).b.x, edgeList.get(i).b.y);//draws the line from x and y cords of where it starts to end
//page.fillOval (edgeList.get(i).b.x-3, edgeList.get(i).b.y-3, 6, 6);
//page.drawString (String.valueOf(point1.x*(point2.y-point3.y)+point2.x*(point3.y-point1.y)+point3.x*(point1.y-point2.y)), 5, 15);
alpha = Math.atan((double)(edgeList.get(i).b.y-edgeList.get(i).a.y)/(edgeList.get(i).b.x-edgeList.get(i).a.x));//alpha = b.y-a.y cords/b.x-a.x chords as a double variable
if (edgeList.get(i).a.x > edgeList.get(i).b.x)//if the x chord of a is greater than the x cordinate of b
{
alpha = alpha + Math.PI;//then alpha = previously defined alpha multiplied by PI
}
if (edgeList.get(i).a.x < edgeList.get(i).b.x && edgeList.get(i).a.y > edgeList.get(i).b.y)//if a.x is less than b.x and a.y is less than b.y
{
alpha = alpha + 2*Math.PI;//then alpha becomes the previously defined alpha multiplied by 2 PI
}
arrow(page,edgeList.get(i).b.x,edgeList.get(i).b.y,0,1.57-alpha);//arrow method, taking a x(edgeList.get(i).b.x, y(edgeList.get(i).b.y, length = 0 so arrow is at the
// very end of the drawn line subtracted by a double aplha
}
}
// arrow method to call when making an arrow
private void arrow(Graphics page, int x, int y, int len, double alpha)//arrow method, taking a x, y, length and double parameter
{
page.setColor (Color.green);//sets arrow to green
int x1 = x+(int)(len*Math.sin(alpha));//x1 is set to x plus length *sin of alpha
int y1 = y+(int)(len*Math.cos(alpha));//y1 is set to y plus the length * cosin of alpha
page.drawLine (x, y, x1, y1);//drawa the x and y, and then previously defined x1, and y1
page.drawLine (x1, y1, x1+(int)(20*Math.sin(alpha+2.5)), y1+(int)(20*Math.cos(alpha+2.5)));//arithmatic to draw one side of the line for the arrow
page.drawLine (x1, y1, x1+(int)(20*Math.sin(alpha+3.7)), y1+(int)(20*Math.cos(alpha+3.7)));//arithmatic to draw the corresponding line for the arrow to complete the arrow
}
// The listener for mouse events.
private class GraphListener implements MouseListener, MouseMotionListener//GraphListener which implements MouseListener and MouseMotionListener, meaning it takes methods from both of those classes
{
public void mouseClicked (MouseEvent event)//when mouse is clicked and released
{
if (mode == true)//if the mode is true
{
nodeList.add(event.getPoint());//the current point to the nodeList
repaint();//whenever you change the look of a componenet you call this method
}
if (mode == false)//if boolean mode is false
{
for (int i=0; i<nodeList.size(); i++)//for loop to go through the nodeList ArrayList
{
if (distance(nodeList.get(i), event.getPoint()) < SIZE)//if the distance between a specific node and the pointer is less than the radius of the node (SIZE)
nodeList.remove(i);//then remove that node
}
for (int i=0; i<edgeList.size(); i++)
{
if (distance(edgeList.get(i).a, event.getPoint())+distance(event.getPoint(), edgeList.get(i).b)-distance(edgeList.get(i).a, edgeList.get(i).b) < SIZE)
//if the (distance between starting point of that edgelist index and the current point) plus (the distance between the current point and ending point of that edgeList index)
//subtracted by the (distance of the starting and ending point of that edgeList index)(AB+BC-AC) is all less than the size
edgeList.remove(i);//then remove that index
}
}
}
public void mousePressed (MouseEvent event)//when the mouse is pressed down
{
if (mode == true)//if the mode is true
{
point1 = event.getPoint();//you start that point
}
}
public void mouseDragged (MouseEvent event)//when the mouse is dragged while pressed down
{
if (mode == true)//if the mode is true
{
point2 = event.getPoint();//then you get the second point
repaint();//must use this method because you are making a change to the component
}
}
public void mouseReleased (MouseEvent event)//when the mouse is released after being pressed (not to be confused with a click)
{
if (mode == true)//if the mode is true
{
point2 = event.getPoint();//then you set point2 to where that point landed
if (point1.x != point2.x && point1.y != point2.y)//if the points are not in the same spots
{
edgeList.add(new Edge(point1,point2));//then you add a new edgeList element to the ArrayList, by definition of Edge() object
repaint();//must use this method because changes to component have been made
}
}
}
public void mouseMoved (MouseEvent event)// if the mouse is moved, without it being clicked (not to be confused by mouseDragged)
{
point3 = event.getPoint();//point three is set to be where the mouse is at the current time(used this to find the distance of original edge drawn, keeping here incase I want to add)
repaint();//must use this method because changes were made to component
}
// Empty definitions for unused event methods.
public void mouseEntered (MouseEvent event){}//when the mouse enters a component
public void mouseExited (MouseEvent event) {}//when the mouse exits a component
private int distance(Point p1, Point p2) //private distance formula but inside of this class so i was able to use it for determining how to erase nodes and edges
{
return (int)Math.sqrt((p1.x-p2.x)*(p1.x-p2.x)+(p1.y-p2.y)*(p1.y-p2.y));//square root of x cordinants of first point minus second point times its self plus the y coordinates
//of first point minus second point times itself
}
}
// Represents the graph edges
private class Edge //defines how edges are made
{
Point a, b;
public Edge(Point a, Point b)
{
this.a = a;
this.b = b;
}
}
private class ButtonListener implements ActionListener
{
public void actionPerformed (ActionEvent event)
{
if (event.getSource()== create)
{
mode = true;
mode1 = 1;
}
if (event.getSource()==delete)
{
mode = !true;
mode1 = 2;
}
// Initializes graph adjacency matrix
for (int i=0; i<nodeList.size(); i++)
for (int j=0; j<nodeList.size(); j++) a[i][j]=0;
// Includes the edges in the graph adjacency matrix
for (int i=0; i<edgeList.size(); i++)
{
for (int j=0; j<nodeList.size(); j++)
if (distance(nodeList.get(j),edgeList.get(i).a)<=SIZE+3)
for (int k=0; k<nodeList.size(); k++)
if (distance(nodeList.get(k),edgeList.get(i).b)<=SIZE+3)
{
System.out.println(j+"->"+k);
a[j][k]=1;
}
}
if (event.getSource()==print)
{
// Prints the graph adjacency matrix
for (int i=0; i<nodeList.size(); i++)
{
for (int j=0; j<nodeList.size(); j++)
System.out.print(a[i][j]+"\t");
System.out.println();
}
}
}
// Euclidean distance function
private int distance(Point p1, Point p2)
{
return (int)Math.sqrt((p1.x-p2.x)*(p1.x-p2.x)+(p1.y-p2.y)*(p1.y-p2.y));
}
}
private class ButtonListener1 implements ActionListener
{
public void actionPerformed (ActionEvent event)
{
if (event.getSource()== create)//if create button is selected
{
mode = true;//then the mode is set to true
mode1 = 1;//and mode1 is set to 1
}
}
}
private class ButtonListener2 implements ActionListener
{
public void actionPerformed (ActionEvent event)
{
if (event.getSource()== delete)//if create button is selected
{
mode = !true;//then the mode is set to true
mode1 = 2;//and mode1 is set to 2, which would change the string that is output
}
}
}
private class ButtonListener3 implements ActionListener
{
public void actionPerformed (ActionEvent event)
{
x1 = label.getText();
y1 = label1.getText();
x = Integer.parseInt(x1);
y = Integer.parseInt(y1);
System.out.println("Path from " +x+" to " +y);
System.out.println(findPath(x,y));
path.add(0,x);
System.out.println(path);
path.clear();
}
}
// private class ButtonListener4 implements ActionListener
// {
// public void actionPerformed (ActionEvent event)
// {
// x1 = label.getText();
// y1 = label1.getText();
// x = Integer.parseInt(x1);
// y = Integer.parseInt(y1);
// System.out.println("Path from " +x+" to " +y);
// System.out.println(findPath1(x,y,path));
// System.out.println(path);
// }
// }
}