main.java

Java编写的编译器前端

package lexer;		// File Main.java
import java.io.*;
public class Main {
	public static void main(String[] args) throws IOException {
		Lexer lex = new Lexer();
		for(;;){
			Token k = lex.scan();	
			lex.words.put( lex.scan().toString() , lex.scan() );
			System.out.print( k.toString()+'\t' );
			if( k instanceof Num )
				System.out.println( "Number" );
			else if( k instanceof Real )
				System.out.println( "Real N" );
			else if( k instanceof Word )
				System.out.println( "Words"  );
			else 
				System.out.println( "Normal Token" );
		}
//		System.out.println("end of file\n");
	}
}