2019年05月05日 开源的IP 地址定位库 ip2region 1.9.0 发布了，功能还是很不错的，下面我就应用下ip2region，来解析ip的地址

一、下载ip库并解压
地址为：https://github.com/lionsoul2014/ip2region/archive/v1.9.0-release.tar.gz
解压

把ip2region.db粘贴到我们maven工程的resources下

二、添加ip2region依赖

<dependency><groupId>org.lionsoul</groupId><artifactId>ip2region</artifactId><version>1.7.2</version>
</dependency>

三、实现IPUtil工具类

import java.io.File;
import java.lang.reflect.Method;import org.lionsoul.ip2region.DataBlock;
import org.lionsoul.ip2region.DbConfig;
import org.lionsoul.ip2region.DbSearcher;
import org.lionsoul.ip2region.Util;public class IPUtil {public static String getCityInfo(String ip){//dbString dbPath = IPUtil.class.getResource("/ip2region.db").getPath();File file = new File(dbPath);if ( file.exists() == false ) {System.out.println("Error: Invalid ip2region.db file");}//查询算法int algorithm = DbSearcher.BTREE_ALGORITHM; //B-tree//DbSearcher.BINARY_ALGORITHM //Binary//DbSearcher.MEMORY_ALGORITYM //Memorytry {DbConfig config = new DbConfig();DbSearcher searcher = new DbSearcher(config, dbPath);//define the methodMethod method = null;switch ( algorithm ){case DbSearcher.BTREE_ALGORITHM:method = searcher.getClass().getMethod("btreeSearch", String.class);break;case DbSearcher.BINARY_ALGORITHM:method = searcher.getClass().getMethod("binarySearch", String.class);break;case DbSearcher.MEMORY_ALGORITYM:method = searcher.getClass().getMethod("memorySearch", String.class);break;}DataBlock dataBlock = null;if ( Util.isIpAddress(ip) == false ) {System.out.println("Error: Invalid ip address");}dataBlock  = (DataBlock) method.invoke(searcher, ip);return dataBlock.getRegion();} catch (Exception e) {e.printStackTrace();}return null;
}}

四、测试
这里我是用的Junit进行单元测试，你也可以自己写个main方法测试即可
添加junit依赖

<dependency><groupId>junit</groupId><artifactId>junit</artifactId><version>4.12</version>
</dependency>

编写测试类

import org.junit.After;
import org.junit.Before;
import org.junit.Test;public class IPUtilTest {private IPUtil ipUtil;@Beforepublic void setUp(){ipUtil=new IPUtil();}@Afterpublic void tearDown(){ipUtil=null;}@Testpublic void getCityInfo(){String ip = "220.248.12.158";System.out.println(ipUtil.getCityInfo(ip));}
}

总结:很方便，其实我觉得比纯真的要好多了~