第一种方式: Socket模拟
利用Socket的connect(SocketAddress endpoint, int timeout)方法可以实现telnet的功能，如果catch到异常说明telnet失败
Socket server = new Socket();
InetSocketAddress address = new InetSocketAddress("192.168.0.113",
8080);
server.connect(address, 5000);
server.close();
} catch (UnknownHostException e) {
System.out.println("telnet失败");
} catch (IOException e) {
System.out.println("telnet失败");
}
import org.apache.commons.net.telnet.TelnetClient;
import java.io.*;
import java.nio.ByteBuffer;
public class TelnetUtil {
String charset = null;
byte[] buff = new byte[2048];
TelnetClient telnetClient = new TelnetClient();
BufferedReader telnetReader = null;
BufferedWriter telnetWirter = null;
InputStream telnetIn = null;
OutputStream telnetOut = null;
public TelnetUtil() {
telnetClient = new TelnetClient();
}
/**
* 连接至服务器
* @param ip
* @param port
* @throws UnsupportedEncodingException
* @throws IOException
*/
public void connect(String ip, int port) throws UnsupportedEncodingException,IOException {
telnetClient.connect(ip,port);
setIOStream();
}
/**
* 连接至服务器
* @param ip
* @throws UnsupportedEncodingException
* @throws IOException
*/
public void connect(String ip) throws UnsupportedEncodingException,IOException {
telnetClient.connect(ip);
setIOStream();
}
void setIOStream() throws UnsupportedEncodingException {
telnetIn = telnetClient.getInputStream();
telnetOut = telnetClient.getOutputStream();
if(null==charset){
telnetReader = new BufferedReader(new InputStreamReader(telnetIn));
telnetWirter = new BufferedWriter(new OutputStreamWriter(telnetOut));
}else{
telnetReader = new BufferedReader(new InputStreamReader(telnetIn, charset));
telnetWirter = new BufferedWriter(new OutputStreamWriter(telnetOut, charset));
}
}
/**
* 登录
* @param user
* @param passwd
* @return 是否登录成功.
* @throws IOException
*/
public boolean login(String user,String passwd) throws IOException {
String read = readString();
for(int i=0; ; i++){
if(-1==read.indexOf("login")){
read = readString();
}else{
break;
}
}
writeText(user);
read = readString();
for(int i=0; ; i++){
if(-1==read.indexOf("Password")){
read = readString();
}else{
break;
}
}
writeText(passwd);
for(;;){
read = readString();
//System.out.println("last:"+read);
if(-1!=read.indexOf("Last")){
return true;
}else if(-1!=read.indexOf("incorrect")){
return false;
}
}
}
/**
* 这是一个测试方法,随便写。
* @throws IOException
*/
public void show() throws IOException {
// System.out.println(readString());
// System.out.println(readString());
// ByteBuffer tmp = ByteBuffer.allocate(1024);
// byte[] buff = new byte[1024];
// while(telnetIn.available()>0){
// int readLen = readBytes(buff,0,1024);
// tmp.put(buff,0,readLen);
// }
// System.out.println(new String(tmp.array()));
System.out.println("1 "+readString());
System.out.println("2 "+readString());
System.out.println("3 "+readString());
writeText("root");
System.out.println("4 " + readString());
writeText("123456");
System.out.println("5 "+readString());
// System.out.println("6 "+readString());
// System.out.println("7 "+readString());
}
public int readBytes(byte[] buff, int offset, int len) throws IOException {
return telnetIn.read(buff,offset,len);
}
/**
* 读取字符串<br/>
* 相当于readByte()转为字符串
* @return
* @throws IOException
*/
public String readString() throws IOException {
int readLen = readBytes(this.buff, 0, this.buff.length);
if(0<readLen)
return new String(buff,0,readLen).trim();
else
return "";
}
/**
* 读取一行<br/>
* 如果服务器与客户端不是同一种操作系统，可能导致此方法计行失败。
* @return
* @throws IOException
*/
public String readLine() throws IOException {
String read = telnetReader.readLine();
return null==read?"":read.trim();
}
public void writeBytes(byte[] buff, int offset, int len) throws IOException {
telnetOut.write(buff,offset,len);
}
/**
* 向服务器写字符串
* @param text
* @throws IOException
*/
public void writeText(String text) throws IOException {
telnetWirter.write(text);
telnetWirter.write('\r');
telnetWirter.write('\n');
telnetWirter.flush();
}
/**
* 执行命令，并返回结果<br/>
* 相当于: <br>
* writeText(); <br/>
* return readString();
* @param cmd
* @return
* @throws IOException
*/
public String exec(String cmd) throws IOException {
writeText(cmd);
return readString();
}
String login1(String user,String passwd) throws IOException {
String read = null;
readString();
readString();
read = readString();
if(-1!=read.indexOf("login")){
writeText(user);
}
read = readString();
if(-1!=read.indexOf("Password")){
writeText(passwd);
}
read = readString();
read += readString();
return read;
// StringBuffer sb = new StringBuffer();
// while(null!= (read = readString())){
// sb.append(read);
// }
//
// return sb.toString();
}
/**
* 关闭
*/
public void close(){
try{
writeText("exit");
writeText("exit");
writeText("exit");
}catch(Exception ex){
}
try {
if(null!=telnetIn) telnetIn.close();
} catch (Exception e) {
}
try {
if(null!=telnetOut) telnetOut.close();
} catch (Exception e) {
}
try {
if(null!=telnetClient)telnetClient.disconnect();
} catch (Exception e) {
}
}
/**
* 设置telnet通信时的字符集<br/>
* 注:此字符集与服务器端字符集没有必然关系<br/>
* 此方法需在connect()前调用
* @param charset
*/
public void setCharset(String charset ){
this.charset = charset;
}
/**
* 重新设置buff大小,默认为2048字节.
* @param size
*/
public void setBufferSize(int size){
this.buff = new byte[size];
}
}
<dependency>
<groupId>commons-net</groupId>
<artifactId>commons-net</artifactId>
<version>3.3</version>
</dependency>