brackettoken.java

来自「是有关解释器的.用JAVA编写.可以解释一般的JAVA程序.」· Java 代码 · 共 66 行

/**
 * Contains one bracket from the following set: '(', ')', '{', '}'.
 */
public class BracketToken extends Token {
    private char symbol;

    BracketToken(int l, int p, char c) {
        super(l, p);
        symbol = c;
    }

    /**
     * @see #isLeftBracket()
     * @see #isRightBracket()
     * @see #isOpenBlock()
     * @see #isCloseBlock()
     */
    char content() {
        return symbol;
    }

    boolean isBracket() {
        return true;
    }

    /**
     * Is the bracket a '('?
     * 
     * @see #content()
     */
    boolean isLeftBracket() {
        return symbol == '(';
    }

    /**
     * Is the bracket a ')'?
     * 
     * @see #content()
     */
    boolean isRightBracket() {
        return symbol == ')';
    }

    /**
     * Is the bracket a '{'?
     * 
     * @see #content()
     */
    boolean isOpenBlock() {
        return symbol == '{';
    }

    /**
     * Is the bracket a '}'?
     * 
     * @see #content()
     */
    boolean isCloseBlock() {
        return symbol == '}';
    }

    public String toString() {
        return "Bracket <" + symbol + ">";
    }
}