input.java

编译原理的课程设计

package source;

import java.io.BufferedReader;
import java.io.InputStreamReader;
//流管理类
public class Input
{
	//缓冲读取器
	private static BufferedReader bufrd = new BufferedReader(new InputStreamReader(System.in));
	public static int line = -1;
	//读取一行
	public static String newLine()
	{
		String exp = null;
		try
		{
			exp = bufrd.readLine();
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		if(exp == null)
			return null;
		else
		{
			line++;
			return exp + '\n';
		}
	}
	//关闭流
	public static void close()
	{
		try
		{
			bufrd.close();
		}
		catch(Exception e) 
		{
	    	e.printStackTrace();
		}
	}
}