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

 1 public class KuohaoJiancha {
 2     private char [] item = {'(',')','[',']','{','}'};
 3     private MyStack stack = new MyStack();
 4     private char[] str;
 5     private int currentNum;
 6     public KuohaoJiancha(String str){
 7         this.str = str.toCharArray();;
 8     }
 9 
10     public boolean display(){
11         for(int i = 0; i < str.length; i++){
12             currentNum = charNumber(str[i]);
13             if(misByStackIsEmpty(str[i]))
14                 return false;
15 
16             if(currentNum % 2 == 1) {
17                 if (currentNum - charNumber((char) stack.pop()) != 1)
18                     return false;
19             }
20             else stack.push(str[i]);
21         }
22         return true;
23     }
24 
25     private int charNumber(char c){
26         int i = 0;
27         for(; i < 6; i++){
28             if(c == item[i])
29                 break;
30         }
31         return i;
32     }
33 
34     private boolean misByStackIsEmpty(char c){//如果读入一个封闭符号,空栈时报错
35         if(stack.isEmpty())
36             if(currentNum % 2 == 1)
37                 return true;
38         return false;
39     }
40 
41 }