java版括号匹配检测

做一个空栈,读入字符直到结尾.如果读入一个封闭符号,空栈时报错;非空时弹出栈尾字符,如果不匹配则报错.否则读入为开放字符,压入栈中.最后如果栈空,返回true.

其中用到MyStack类,详情请见

public class KuohaoJiancha {
    private char [] item = {'(',')','[',']','{','}'};
    private MyStack stack = new MyStack();
    private char[] str;
    private int currentNum;
    public KuohaoJiancha(String str){
        this.str = str.toCharArray();;
    }

    public boolean display(){
        for(int i = 0; i < str.length; i++){
            currentNum = charNumber(str[i]);
            if(misByStackIsEmpty(str[i]))
                return false;

            if(currentNum % 2 == 1) {
                if (currentNum - charNumber((char) stack.pop()) != 1)
                    return false;
            }
            else stack.push(str[i]);
        }
        return true;
    }

    private int charNumber(char c){
        int i = 0;
        for(; i < 6; i++){
            if(c == item[i])
                break;
        }
        return i;
    }

    private boolean misByStackIsEmpty(char c){//如果读入一个封闭符号,空栈时报错
        if(stack.isEmpty())
            if(currentNum % 2 == 1)
                return true;
        return false;
    }

}