getchar.java

来自「可以实现.txt和.pas文件的词法分析,提供给大家参考和学习」· Java 代码 · 共 49 行

package PL0;

import PL0.EventDo;
import PL0.ErrorException;
import java.io.*;
import java.util.*;
import java.lang.reflect.*;


public class GetChar{
	static String filepath;
	static String s;	   
	static char[] line;
    public static char ch=' ';
    static int current=0;
	static int length=0;
    static Iterator<String> it;
	public GetChar(String fp) throws IOException{
		filepath=fp;
		LinkedList<String> file=new LinkedList<String>();
	    BufferedReader in=new BufferedReader(new FileReader(filepath));
	    while((s=in.readLine())!=null){
	    file.addLast(s);
	    }
    it=file.iterator();
	}
	public static int getchar() throws IOException{
		BufferedReader in=new BufferedReader(new FileReader(filepath));
		if(current==length){
        	try{
        		if(!it.hasNext()){
        			throw new ErrorException();
        			}
        	}catch(ErrorException err){
        		EventDo.errorinfor.setText("dsfdgfdgfdg");
        		return -1;	
        	}
        	s=it.next();
        	current=0;
        	length=Array.getLength(s.toCharArray());
        	line=new char[length+1];
        	line=s.toCharArray();
	    }
	    ch=line[current];
	    current++;
	    in.close();
	    return 0;
}	
}