使用InputStream和OutputStream来获得命令行运行结果和输入内容是首先需要具备的.
然后要解决SSH连接问题.
在OpenSource项目里找到了Ganymed SSH-2 for Java .下载后有例子,但是没有找到有关交互命令的例子.所以自己探索了一下
在网上看有老外讨论用这个如何改密码,基本上的问题都是因为找不到返回的提示
Linux修改密码输入passwd后,首先是输入当前密码,然后是输入两个新密码
如果当前密码输入错误,或者新密码输入不符合系统密码规则要求,会要求重新输入.如果碰到这种情况,程序很容易进入一个不太好控制的循环.
可能一般人都认为输入命令后所有的返回都应该是用session.getStdout();而不是session.getStderr();从方法名称上看确实如此,一个是取得标准输出,一个是取得错误信息.
其实在输入passwd后.
Changing password for user [username].
Changing password for [username]
这两行是需要通过session.getStdout();来获得的.但是后面的
(current) UNIX password:
New UNIX password:
Retype new UNIX password:
这三行是需要使用sessssion.getStderr();来获取的
如果用户输入没有通过系统检测,会返回具体原因,但是都是BAD PASSWORD开始的.
如果最后修改成功了.你也会看到有successfully来表示.这些信息是通过session.getStdout();来获取的.
现在问题很好解决了吧.
写了一个类来完成修改密码的操作
import ch.ethz.ssh2.Connection;
import ch.ethz.ssh2.Session;
import ch.ethz.ssh2.StreamGobbler;
import com.io.Debug;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
public class ChangeEmailPassword {
private String username = "";
private String oldpassword = "";
private Connection conn = null;
private boolean hasError = false;
private String ErrorMessage = "";
private boolean isSuccessfully = false;
private String SystemMessage = "";
public static final String HOST = "127.0.0.1"; //server ip
public boolean isSuccessfully(){
return isSuccessfully;
}
public boolean isHasError(){
return hasError;
}
public String getErrorMessage(){
return ErrorMessage;
}
public void setErrorMessage(String msg){
hasError = true;
this.ErrorMessage = msg;
}
public ChangeEmailPassword(String username,String oldpassword) {
this.username = username;
this.oldpassword = oldpassword;
try{
conn = new Connection(HOST);
conn.connect();
boolean isAuthenticated = conn.authenticateWithPassword(username, oldpassword);
if (isAuthenticated == false) {
setErrorMessage("Authentication failed.");
conn=null;
}
}catch(Exception e){
conn.close();
conn = null;
System.out.println(e);
}
}
public void setNewPassword(String newpassword) {
if(hasError){
return;
}
if (conn==null){
return;
}
try{
Session sess = conn.openSession();
sess.execCommand("passwd");
InputStream so = sess.getStdout();
InputStream err = sess.getStderr();
OutputStream out = sess.getStdin();
byte[] buffer = new byte[500];//其实没有必要这么大.130就差不多了.怕万一有什么提示.
int length = 0;
length = err.read(buffer);
// if (length > 0) {
// System.out.println("#1:"+ new String(buffer, 0, length));
// //(current) UNIX password:
// }
String coldpassword = oldpassword+"\n";
out.write(coldpassword.getBytes());
length = err.read(buffer);
// if (length > 0) {
// System.out.println("#2:"+ new String(buffer, 0, length));
// //(current) UNIX password:
// }
String cnewpass = newpassword +"\n";
out.write(cnewpass.getBytes());
length = err.read(buffer);
if (length > 0) {
String rs = new String(buffer, 0, length);
//System.out.println("#3:"+rs);
if(rs.indexOf("BAD")>-1){
sess.close();
conn.close();
setErrorMessage(rs);
return;
}
}
out.write(cnewpass.getBytes());
length = so.read(buffer);
if (length > 0) {
String rs = new String(buffer, 0, length);
if(rs.indexOf("successfully")>-1){
this.isSuccessfully = true;
this.SystemMessage = rs;
}
}
sess.close();
conn.close();
} catch (IOException e) {
e.printStackTrace(System.err);
}
}
public static void main(String[] args) {
ChangeEmailPassword cep = new ChangeEmailPassword("username", "oldpassword");
if(cep.isHasError()){
System.out.println(cep.getErrorMessage());
cep = null;
return;
}
cep.setNewPassword("newpassword");
if(cep.isHasError()){
System.out.println(cep.getErrorMessage());
cep = null;
return;
}
if(cep.isSuccessfully){
System.out.println(cep.getSystemMessage());
}
}
public String getSystemMessage() {
return SystemMessage;
}
}
//把里面注解掉的System.out.println打开可以看到系统提示的信息.我只保留了最关键的信息提示
