java实现整数反转

	class Solution {
	    public int reverse(int x) {
	    	 long nums = 0;
	    	 int temp = 1;
	    	 try {
		        temp = x / Math.abs(x);
		        StringBuilder num = new StringBuilder();
		        num.append(Math.abs(x));
	        	nums = Long.parseLong(num.reverse().toString());
		    	if(nums > Math.pow(2, 31) - 1) {
		    		return 0;
		    	}
	        } catch (Exception e) {
				// TODO: handle exception
	        	return 0;
			}
	    	return (int)nums*temp;
	    }	
	}

	class Solution {
	    public int reverse(int x) {
	    	int ans = 0;
	    	while(x != 0) {
	    		// 判断溢出
	    		if((ans * 10) / 10 != ans) {
	    			ans = 0;
	    			break;
	    		}
	    		// ans*10 没有溢出
	    		ans = ans * 10 + x % 10;
	    		x /= 10;
	    	}
	    	return ans;
	    }	
	}