Adding instances of a class to an Arraylist

Question

I want to add instances of a class to an arraylist.and here is the code:

ArrayList<Edge> edges = new ArrayList<Edge>(); //A List Containing All the Edges & their startNode,endNode

System.out.println("Enter Number of Nodes: ");
int noOfNodes = scan.nextInt();  //Gets Number of Nodes in Graph

int graphmatrix[][] = new int[noOfNodes][noOfNodes];  //Makes a Matrix According to Graph

for ( int i=0; i < noOfNodes; i++ ) {
    for (int j=0; j < noOfNodes; j++) {
        if ( j > i ) {
            System.out.println("Enter Relation Between " + i + " & " + j + ": ");
            int length = scan.nextInt();
            graphmatrix[i][j] = length;
            graphmatrix[j][i] = length;
            Edge edge = new Edge(i, j, length);
            edges.add(edge);
        }
    }       
}
System.out.println(edges);

and here is the output of last line:

[dijkstra.Edge@49e4cb85, dijkstra.Edge@2133c8f8, dijkstra.Edge@43a25848]

as you can see,the problem seems to be that it doesn't creates the arraylist. I don't understand what is wrong. and also here is the constructor of Edge class:

public Edge(int startNode, int endNode, int length) {
    this.startNode = startNode;
    this.endNode = endNode;
    this.length = length;
}

Looks like you need to loop through each item in the ArrayList and then call System.out.println() — dave, Jun 22 '18 at 17:08
@aquaballin That will only print each `dijkstra.Edge@...` on its own line. — Code-Apprentice, Jun 22 '18 at 17:09
This is correct output -- dijkstra.Edge@49e4cb85 is Javas why of printing a object to a string, it is a class name and a memory location to uniquely identify the object. What output are you expecting? — gbtimmon, Jun 22 '18 at 17:10

Adding instances of a class to an Arraylist

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