what are the benefits of BufferedReader over Scanner

here’s a code about depth first search in graphs. who knows why bufferedReader class were used in this code? and why nextInt function not used instead? what is its privilege? is it for speeding up processing? Thanks 🙂

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
class Graph
{
int g[][];
int v,e;
int visited[];
void createGraph()throws IOException
{
    int a,b;
    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    System.out.print("n Enter Number Of Vertices = ");
    v=Integer.parseInt(br.readLine());
    System.out.print("n Enter Number Of Edges = ");
    e=Integer.parseInt(br.readLine());  
    g=new int[v+1][v+1];
    for(int i=1;i<=e;i++)
    {
        System.out.print("n Enter Edge Infomation ");
        System.out.print("n From =");
        a=Integer.parseInt(br.readLine());
        System.out.print("n To =");
        b=Integer.parseInt(br.readLine());  
        g[a][b]=g[b][a]=1;
    }
}
void callDFS()
{
    visited = new int[v+1];
    dfs(1);
}   
void dfs(int k)
{
    System.out.print(k + "t");
    visited[k]=1;
    for(int i=1;i<=v;i++)
    {
        if(g[k][i] !=0 && visited[i]!=1)
        dfs(i);
    }
}
}
class DFS
{
public static void main(String args[])throws IOException
{
    Graph g = new Graph();
    g.createGraph();
    g.callDFS();
}
}

Answer

It’s an issue of how you intend to use the stream. A buffered reader exists for simple and threaded applications. This is due to scanner’s lack of thread safety.

I think you’ll get more on this from this question Scanner vs. BufferedReader