public class HelloWorld {
    public static void main(String[] args) {
        String str = "a(1,(2,3),4)b,bc(4,5),(6,7)cd";
        /*
         * how to get:
         * 
         * 1. a(1,(2,3),4)b
         * 2. bc(4,5)
         * 3. (6,7)cd
         */
    }
}

public static void main(String[] e) {
        String str = "a(1,(2,3),4)b,bc(4,5),(6,7)cd";
        char[] cs = str.toCharArray();
        int layer = 0;
        List<Integer> indexs = new ArrayList<Integer>();
        List<String> strs = new ArrayList<String>();
        for(int i = 0; i < cs.length; i++){
            if(layer == 0 && ',' == cs[i]){
                indexs.add(new Integer(i));
            }
            if('('== cs[i]){
                layer++;
            }else if(')'== cs[i] && layer > 0){
                layer--;
            }
        }
        for(int i = 0; i < indexs.size(); i++){
            if(i == 0){
                strs.add(str.substring(0, indexs.get(i)));
            }else{
                strs.add(str.substring(indexs.get(i - 1) + 1, indexs.get(i)));
            }
            if( i == indexs.size() - 1){
                strs.add(str.substring(indexs.get(i) + 1));
            }
        }
        
        for(String ss : strs){
            System.out.println(ss);
        }
    }

------解决方案--------------------

Java code

//改一个bug
public static void main(String[] args) {
        String str = "a(1,(2,3),4)b,bc(4,5),(6,7)cd,qwqw";
        String arr[] = str.split(",(?=[^)(]*?(\\([^)(]*?\\),?)*[^)(]*$)");
        for(int i=0;i<arr.length;i++){
            System.out.println(arr[i]);
        }
    }