54 CHEN

改写java TreeMap制造方便查询的ip内存库

ip

国库流行的ip库记录数大约在6万条左右,数据格式大约都是如下:
start,end,country…
要查询的时候都是放到mysql里去,然后select * from ip where start>=xx and end end <=xx来得到ip信息,我(54chen)在搞一个实时监控时,因为并发量非常大,全部查询IP库,需要好几万每秒的查询,特改了java的TreeMap的get方法,将所有数据放到内存里来作,put的时候还是保持TreeMap的红黑树实现,以start作为key,而在get的时候有一个 compare的过程,在发现compare是大于0的时候进行如下修改:

else if (cmp > 0) {
int start = ((Data) p.value).getStart();
int end = ((Data) p.value).getEnd();
int intKey = Integer.parseInt(k.toString());
if (intKey >= start && intKey <= end) {
return p;
} p = p.right;
}

大概意思是:在树上遇到比要找的数据小的节点时,从数据中取到end的大小,来参加对比,如果满足要求,直接返回。

附修改好的代码: http://ishare.iask.sina.com.cn/f/15805095.html

重要补充:

由qunar的sunli大侠补充,用实现comparable的key用法更加正宗,代码如下:

public class Chen {
public static void main(String[] args) {

java.util.TreeMap<IpEntry, Data> xmap = new java.util.TreeMap<IpEntry, Data>();
xmap.put(new IpEntry(0, 100), genData(0, 100, “"));
xmap.put(new IpEntry(101, 200), genData(101, 200, “小”));
xmap.put(new IpEntry(2000, 3000), genData(2000, 3000, “佬”));
xmap.put(new IpEntry(201, 300), genData(201, 300, “巴西”));
xmap.put(new IpEntry(501, 600), genData(501, 600, “法国”));
xmap.put(new IpEntry(701, 800), genData(701, 800, “英国”));
xmap.put(new IpEntry(601, 700), genData(601, 700, “"));
xmap.put(new IpEntry(1601, 1700), genData(1601, 1700, “广州”));

Data data = xmap.get(new IpEntry(1260, 1260));
if (data == null) {
System.out.println(“not found!");
} else {
System.out.println(data.getCountry());
} }

private static class IpEntry implements Comparable {

final long start;
final long end;

IpEntry(long start, long end) {
this.start = start;
this.end = end;
}

public int compareTo(IpEntry t) {
long t1 = start - t.start;
if (t1 < 0) {
return -1;
} long t2 = end - t.end;
if (t1 >= 0 && t2 <= 0) {
return 0;
} return 1;
}

}

private static Data genData(int start, int end, String country) {
Data data = new Data();
data.setCountry(country);
data.setStart(start);
data.setEnd(end);
return data;
} }

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Posted by 54chen java