本代码的实现前提：
1.拥有阿里云域名，且获取了Access Key 及 Access Secret
2.能获取外网IP的页面地址（注意：ip138.com的实际包含ip地址为http://2018.ip138.com/ic.asp）
Maven依赖项：
<dependencies>
<!-- https://mvnrepository.com/artifact/org.apache.httpcomponents/httpclient -->
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.5</version>
</dependency> <!-- https://mvnrepository.com/artifact/com.google.code.gson/gson -->
<dependency>
<groupId>com.google.code.gson</groupId>
<artifactId>gson</artifactId>
<version>2.8.5</version>
</dependency> <!-- https://mvnrepository.com/artifact/com.aliyun/aliyun-java-sdk-core -->
<dependency>
<groupId>com.aliyun</groupId>
<artifactId>aliyun-java-sdk-core</artifactId>
<version>4.0.2</version>
</dependency> <dependency>
<groupId>com.aliyun</groupId>
<artifactId>aliyun-java-sdk-alidns</artifactId>
<version>2.0.6</version>
</dependency> </dependencies>
代码：
package com.phipsoft.aliyun.ddns; import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern; import com.aliyuncs.DefaultAcsClient;
import com.aliyuncs.IAcsClient;
import com.aliyuncs.alidns.model.v20150109.DescribeDomainRecordsRequest;
import com.aliyuncs.alidns.model.v20150109.DescribeDomainRecordsResponse;
import com.aliyuncs.alidns.model.v20150109.DescribeDomainRecordsResponse.Record;
import com.aliyuncs.alidns.model.v20150109.UpdateDomainRecordRequest;
import com.aliyuncs.alidns.model.v20150109.UpdateDomainRecordResponse;
import com.aliyuncs.profile.DefaultProfile;
import com.aliyuncs.profile.IClientProfile; public class DDNS {
static final String CHARSET_ENCONDING = "utf-8";
static final String KEY_IP_URL = "-url";
static final String KEY_IP_REGEX_PATTERN = "-reg";
static final String KEY_ACCESS_KEY = "-k";
static final String KEY_ACCESS_SECRET = "-s";
static final String KEY_DOMAIN = "-d";
static final String KEY_RR = "-rr"; public static String sendGet(String url, String param) {
String result = "";
BufferedReader in = null;
try {
String urlNameString = url + ((param == null || param.isEmpty())? "" : ("?" + param));
URL realUrl = new URL(urlNameString);
// 打开和URL之间的连接
URLConnection connection = realUrl.openConnection();
// 设置通用的请求属性
connection.setRequestProperty("accept", "*/*");
connection.setRequestProperty("connection", "Keep-Alive");
connection.setRequestProperty("contentType", CHARSET_ENCONDING);
connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)"); // 建立实际的连接
connection.connect(); in = new BufferedReader(new InputStreamReader(connection.getInputStream(), CHARSET_ENCONDING));
String line;
while ((line = in.readLine()) != null) {
result += line;
}
} catch (Exception e) {
e.printStackTrace();
}
// 使用finally块来关闭输入流
finally {
try {
if (in != null) {
in.close();
}
} catch (Exception e2) {
e2.printStackTrace();
}
}
return result;
} private static final String getInternetIP(String url, String regexPattern) {
String ret = null;
String html = sendGet(url, null);
Pattern pattern = Pattern.compile(regexPattern);
Matcher matcher = pattern.matcher(html);
if(matcher.find()) {
ret = matcher.group(0);
}
return ret;
} private static void updateIP(Map<String, String> config) throws Exception {
String ip = null;
if(config.containsKey(KEY_IP_URL) && config.containsKey(KEY_IP_REGEX_PATTERN)) {
ip = getInternetIP(config.get(KEY_IP_URL), config.get(KEY_IP_REGEX_PATTERN));
}else {
throw new RuntimeException("获取外网ip的参数不足");
}
IClientProfile clientProfile = DefaultProfile.getProfile("cn-hangzhou", config.get(KEY_ACCESS_KEY), config.get(KEY_ACCESS_SECRET));
IAcsClient client = new DefaultAcsClient(clientProfile);
DescribeDomainRecordsRequest request = new DescribeDomainRecordsRequest();
request.setDomainName(config.get(KEY_DOMAIN));
DescribeDomainRecordsResponse response;
boolean flag = false;
response = client.getAcsResponse(request);
for(Record record : response.getDomainRecords()) {
if(record.getRR().equalsIgnoreCase(config.get(KEY_RR))&&record.getType().equalsIgnoreCase("A")) {
String old_ip = record.getValue();
String cur_ip = ip;
flag = true;
if(!old_ip.equals(cur_ip)){
UpdateDomainRecordRequest udr_req = new UpdateDomainRecordRequest();
udr_req.setValue(cur_ip);
udr_req.setType(record.getType());
udr_req.setTTL(record.getTTL());
udr_req.setPriority(record.getPriority());
udr_req.setLine(record.getLine());
udr_req.setRecordId(record.getRecordId());
udr_req.setRR(record.getRR());
UpdateDomainRecordResponse udr_resp = client.getAcsResponse(udr_req);
System.out.println(udr_resp.toString());
}else{
System.out.println("不需要修改");
}
}
}
if(flag == false) {
throw new RuntimeException("无法找到RR="+config.get(KEY_RR));
} } private static Map<String,String> parseArgs(String[] args){
Map<String,String> ret = new HashMap<String, String>();
for(int i=0;i<args.length;) {
if(args[i].startsWith("-")) {
ret.put(args[i], args[i+1]);
i+=2;
}else {
i++;
}
}
return ret;
} /**
* -k xxx -s xxxx -d xxx.cn -rr www -url xxxx -reg (\d+\.){3}\d+
* @param args
*/
public static void main(String[] args) {
try{
Map<String,String> config = parseArgs(args);
updateIP(config);
}catch(Exception e){
System.out.println(e);
}
}
}
以上代码为简化运行环境，参数没做更多正确性检验， 生成可执行jar包， 通过命令行参数即可实现动态域名解析。再放入计划任务，自动更新……