dataparser.java

使用Java实现的Graph的迭代加深的深度优先搜索

/**
 * 
 */
package run;

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;

import digraph.DiGraph;
import digraph.Graph;
import digraph.Node;

/**
 * @author zhangli
 *
 */
public class DataParser {
	public Graph readGraph(String fileName)
	{
		
		Scanner scanner;
		try {
			scanner = new Scanner(new File(fileName));
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			System.out.println("No such file");
			return null;
		}
		
		Graph graph = new DiGraph();
		Node node1 = null, node2 = null;
		String readin = scanner.next();

		while(scanner.hasNext())
		{
			readin = scanner.next();

			if (readin.endsWith(":"))
			{
				node1 = getOrAdd(graph, readin.substring(0, readin.length()-1));
			}
			else
			{
				node2 = getOrAdd(graph, readin);
				graph.addEdge(node1, node2);
			}
		}
		return graph;
		

	}
	
	private Node getOrAdd(Graph graph, String nodeName) {
		// TODO Auto-generated method stub
		Node node = graph.getNode(nodeName);
		if (node == null)
			return graph.addNode(nodeName);
		else
			return node;
	}
}