keywordtoken.java

是有关解释器的.用JAVA编写.可以解释一般的JAVA程序.

/**
 * Contains a keyword from the following set: "return", "while", "loop", "if",
 * "else", "new", "void", "boolean", "int", "direction", "Robot".
 */
public class KeywordToken extends Token {
    private String keyword;

    KeywordToken(int l, int p, String k) {
        super(l, p);
        keyword = k;
    }

    boolean isKeyword() {
        return true;
    }

    /**
     * @see #isReturn()
     * @see #isWhile()
     * @see #isLoop()
     * @see #isIf()
     * @see #isElse()
     * @see #isNew()
     * @see #isVoid()
     * @see #isBoolean()
     * @see #isInt()
     * @see #isDirection()
     * @see #isRobot()
     */
    String content() {
        return keyword;
    }

    boolean isReturn() {
        return keyword.equals("return");
    }

    boolean isWhile() {
        return keyword.equals("while");
    }

    boolean isLoop() {
        return keyword.equals("loop");
    }

    boolean isIf() {
        return keyword.equals("if");
    }

    boolean isElse() {
        return keyword.equals("else");
    }

    boolean isNew() {
        return keyword.equals("new");
    }

    boolean isVoid() {
        return keyword.equals("void");
    }

    boolean isBoolean() {
        return keyword.equals("boolean");
    }

    boolean isInt() {
        return keyword.equals("int");
    }

    boolean isDirection() {
        return keyword.equals("direction");
    }
    
    boolean isRobot()   {
    	return keyword.equals("Robot");
    }

    public String toString() {
        return "Keyword <" + content() + ">";
    }
}