kwtable.java

这个是java版本的pl0语言的词法分析器,带有图形界面,很好的

package myCompiler;

import java.util.Enumeration;
import java.util.Hashtable;

public class KWTable {
	static Hashtable<String, String> KWHash;
static	String[] sym={"const","var","procedure","if","then",
			"while","do","read","write","begin","end","call","odd"};
	static int symlen=sym.length;
public static void initKWTable(){
	KWHash = new Hashtable<String, String>();
    for(int i=0;i<symlen;i++)
	KWHash.put(Integer.toString(i+1), sym[i]);
}

public  static int findKey(String kword) {
	   int KEY;
	    for (Enumeration<String> e = KWHash.keys(); e.hasMoreElements(); ) {
	      KEY = Integer.parseInt( (String) e.nextElement());
	      if ( ( (String)KWHash.get(Integer.toString(KEY))).
	          equalsIgnoreCase(kword)) {
	        return KEY;
	      }
	    }
	    return -1;
}
}