Java implements Dynamic IP address switching (ADSL dial-up Internet access) Java disconnection and reconnection (original) Solve the Problem of reading cmd message garbled

Http://gezhicheng.javaeye.com/blog/764228

The Implementation of Dynamic IP switching is also provided by the Windows rasdial command. In fact, it is not Java's credit. Java only calls the bat script:

Rasdial command:

 

Dialing

Java Code :

1. Syntax: rasdial connection name Username Password
2. Example: rasdial my broadband hzhz1234567890 dfdfdfdfdf

Network disconnection

Java code

1. Syntax: rasdial connection name/disconnect
2. Instance: rasdial broadband/disconnect

 

JavaProgramCall the rasdial command :(Garbled characters may occur when reading the CMD returned message. Pay attention to the encoding settings of the sentence in the red font.)

Java code

  Package  Com. Sesame. Network;

  Import  Java. Io. bufferedreader;
  Import  Java. Io. inputstreamreader;

  Public     Class  Connectnetwork {

 /**  
* Run the CMD command and return the string.
  */  
  Public     Static  String executecmd (string strcmd)  Throws  Exception {
PROCESS p  =  Runtime.getruntime(cmd.exe C (  "  CMD/C  "    +  Strcmd );
Stringbuilder sbcmd  =     New  Stringbuilder ();
Bufferedreader br  =     New  Bufferedreader (  New  Inputstreamreader (P
. Getinputstream () , "Gb2312"));// This is very important. Set gb2312 to fix Garbled text !!!
// If the default code of the program is gb2312, do not write
// Utf8 is used by default in netbeans.
String line;
  While  (Line  =  BR. Readline ())  ! =     Null  ){
Sbcmd. append (line  +     "  \ N  " );
}
  Return  Sbcmd. tostring ();

// If the entire process is changed to this, it is clearer. Getinputstream is the most primitive byte stream,
// The byte stream returned by CMD is gb2312 dubyte encoding.
 Inputstream in = P. getinputstream ();
Byte [] B = new byte [1000];
In. Read (B );
String MSG = new string (B, "gb2312"); // use gb2312 to explain the heap bytes, And Then assemble them into a normal string.
 // If gb2312 is not written above, it is equivalent to utf8 assembly. The result is the same. 
 }

  /**  
* Connect to ADSL
 */  
  Public     Static     Boolean  Connadsl (string adsltitle, string adslname, string adslpass)  Throws  Exception {
System. Out. println (  "  Establishing connection.  "  );
String adslcmd  =    "  Rasdial  "     +  Adsltitle  +     "     "     +  Adslname  +     "    "  
  +  Adslpass;
String tempcmd  =  Executecmd (adslcmd );
  //  Determine whether the connection is successful  
    If  (Tempcmd. indexof (  "  Connected  "  )  >    0  ){
System. Out. println (  "  The connection has been established successfully.  "  );
  Return     True  ;
}  Else  {
System. Err. println (tempcmd );
System. Err. println (  "  An error occurred while establishing the connection.  " );
  Return     False  ;
}
}

  /**  
* Disconnect ADSL
  */  
  Public     Static     Boolean  Cutadsl (string adsltitle)  Throws Exception {
String cutadsl  =     "  Rasdial  "     +  Adsltitle  +     "  /Disconnect  "  ;
String result  = Executecmd (cutadsl );

  If  (Result. indexof (  "  No connection  "  )  ! =-  1  ){
System. Err. println (adsltitle  +     "  The connection does not exist!  "  );
  Return    False  ;
}  Else  {
System. Out. println (  "  Disconnected  "  );
  Return     True  ;
}
}

  Public     Static    Void  Main (string [] ARGs)  Throws  Exception {
Connadsl (  "  Broadband  "  ,  "  Hzhz **********  "  ,  "  ******  "  );
Thread. Sleep (  1000 );
Cutadsl (  "  Broadband  "  );
Thread. Sleep (  1000  );
  //  Re-connect and assign a new IP Address  
  Connadsl (  "  Broadband  "  ,  "  Hzhz ********** "  ,  "  ******  "  );
}
} 

 

Execution result:

Java code

1. Establishing connection.
2. The connection has been established successfully.
3. Disconnected
4. Establishing connection.
5. The connection has been established successfully.

Summary:
The most important thing to implement this function is that the bat command can support this function, which is similar to the previously written function of automatically setting IP addresses. it is inconvenient to implement these functions in Java, it seems that it is necessary to elegantly implement the behaviors related to the Windows operating system and learn windows programming.

 

 

Redial mechanism:

 

Java code

1. While(! Connadsl ("Broadband","Hzhz **********","******")){
2. Thread. Sleep (1000);

}