如何通過自己的ADSL使家里的電腦成為服務(wù)器呢？像花生殼這樣的應(yīng)用可以幫助你動(dòng)態(tài)解析ip，不過這個(gè)程序太龐大了，根本沒有必要。
下面介紹我的做法：
條件：
? 上網(wǎng)方式：ADSL
? 臺(tái)式機(jī)：linux
? 中繼網(wǎng)頁：在某虛擬主機(jī)申請(qǐng)一個(gè)免費(fèi)空間，需要支持動(dòng)態(tài)腳本（php、jsp等）
方案：
??在本機(jī)運(yùn)行一個(gè)Java程序，定時(shí)讀取本機(jī)的外網(wǎng)IP，自動(dòng)向中繼網(wǎng)頁用GET方式提交該數(shù)據(jù)。中繼網(wǎng)頁保存IP記錄在內(nèi)存中，其他訪問者可以通過該頁面查看當(dāng)前的IP。

package ?tedeyang;

import ?java.io.BufferedReader;
import ?java.io.IOException;
import ?java.io.InputStreamReader;
import ?java.net.InetAddress;
import ?java.net.URL;
import ?java.net.URLConnection;
import ?java.net.UnknownHostException;
import ?java.util.Date;
import ?java.util.Timer;
import ?java.util.TimerTask;

public ? class ?UpdateIp? {
???? static ?String?page? = ? " http://xxx.xxx.com/name/link.jsp?ip= " ; // ?need?'ip='
???? static ?String?strategy? = ? " ifconfig " ; // ?or?jdk
???? static ? long ?refreshTime? = ? 5L ? * ? 60 ? * ? 1000 ;? // ?5?minutes

???? /**?*/ /**
?????*? @param ?args
?????*? @throws ?IOException
????? */
???? public ? static ? void ?main( final ?String[]?args)? throws ?IOException? {
???????? if ?(args.length? <= ? 1 )? {
????????????System.out.println( " Parameter?error?! " );
????????????System.out
????????????????????.println( " should?be?followed?by?three?parameters?:?updatePage?ipStrategy?refreshMinutes,?at?least?updatePage " );
????????????System.out.println( " ????updatePage?likes?'http://host/xxx.jsp?ip=' " );
????????????System.out.println( " ????ipStrategy?maybe?is?jdk?or?ifconfig,default?is?ifconfig " );
????????????System.out.println( " ????refreshMinutes?'s?unit?is?minute,?default?is?5?minutes " );
???????????? return ;
????????}
????????page? = ?args[ 0 ];
???????? if ?( ! page.endsWith( " ip= " ))
????????????page? += ? " ?ip= " ;? // ??
????????strategy? = ?args[ 1 ];
???????? try ? {
????????????refreshTime? = ?Integer.parseInt(args[ 2 ]);
????????????refreshTime? *= ? 60 ? * ? 1000 ;
????????} ? catch ?(Exception?e)? {
????????}
???????? // cycle
???????? final ?Timer?t? = ? new ?Timer();
????????t.schedule( new ?TimerTask()? {
???????????? public ? void ?run()? {
???????????????? try ? {
????????????????????UpdateIp.run(page,?strategy);
????????????????} ? catch ?(IOException?e)? {
????????????????????e.printStackTrace();
???????????????????? // ?t.cancel();
????????????????}
????????????} ;
????????} ,? 0 ,?refreshTime);
????}

???? private ? static ? void ?run(String?page,?String?ipStrategy)? throws ?IOException? {

????????String?ip? = ? " no " ;
???????? if ?(ipStrategy.equals( " jvm " ))
????????????ip? = ?getIpByJavaApi();
???????? else
????????????ip? = ?getIpByLinuxIfconfig();
????????System.out.print( new ?Date()? + ? " ,?this?ip?is?: " ? + ?ip);
????????touchIp(page,?ip);
????????System.out.println( " ?,?touch?successed. " );
????}

???? private ? static ? void ?touchIp(String?page,?String?ip)? throws ?IOException? {
????????URL?url? = ? null ;
????????url? = ? new ?URL(page? + ?ip);
????????URLConnection?con? = ? null ;
????????BufferedReader?reader? = ? null ;
???????? try ? {
????????????con? = ?url.openConnection();
????????????con.connect();
????????????reader? = ? new ?BufferedReader( new ?InputStreamReader(con.getInputStream()));
????????????reader.readLine();
????????} ? finally ? {
???????????? try ? {
????????????????reader.close();
????????????????con? = ? null ;
????????????} ? catch ?(IOException?e)? {
????????????????e.printStackTrace();
????????????}
????????}
????}

???? private ? static ?String?getIpByJavaApi()? throws ?UnknownHostException? {
????????String?ip? = ? " none " ;
????????InetAddress[]?all? = ?InetAddress.getAllByName(InetAddress.getLocalHost()
????????????????.getHostName());
???????? // ?通過本機(jī)主機(jī)名，遍歷多個(gè)ip
???????? for ?( int ?i? = ? 0 ;?i? < ?all.length;?i ++ )? {
????????????String?ip2? = ?all[i].getHostAddress();
???????????? if ?( ! ip2.startsWith( " 127. " )? && ? ! ip2.startsWith( " 192. " )
???????????????????? && ? ! ip2.startsWith( " 10. " )? && ? ! ip2.startsWith( " 172. " ))? {
????????????????ip? = ?ip2;
????????????}
????????}
???????? return ?ip;
????}

???? private ? static ?String?getIpByLinuxIfconfig()? throws ?IOException? {
????????String?ip? = ? " none " ;
????????Process?pre? = ?Runtime.getRuntime().exec(
???????????????? new ?String[]? {? " sh " ,? " -c " ,? " ifconfig?ppp0?|?grep?addr " ?} );
????????BufferedReader?reader? = ? null ;
???????? try ? {
????????????reader? = ? new ?BufferedReader( new ?InputStreamReader(pre
????????????????????.getInputStream()));
????????????String?line? = ?reader.readLine();
???????????? if ?(line? != ? null ? && ?line.matches( " .*addr.* " ))? {
???????????????? int ?s? = ?line.indexOf( " addr: " )? + ? 5 ;
???????????????? int ?e? = ?line.indexOf( " ? " ,?s);
????????????????ip? = ?line.substring(s,?e).trim();
????????????}
????????} ? finally ? {
???????????? if ?(reader? != ? null )
????????????????reader.close();
????????}
???????? return ?ip;
????}

}

?

<%!
static ?String?ip? = ? " none " ;
static ?List?record? = ? new ?ArrayList();
%><%
String?ipa = ?request.getParameter( " ip " );
if (record.size() > 100 ) {
?record.clear();
}
if (ipa? != ? null ) {
? if (ipa.equals( " ask " )) {
?Iterator?it? = ?record.iterator();
while (it.hasNext()) {
out.println(it.next() + " </br> " );
}
} else {
? this .ip? = ?ipa;
?record.add(ipa + " ? " + new ?java.util.Date().getTime());
}
}
out.print( " ip= " + ip);

%>