我没有找到打开如此详细日志记录的方法，而是决定采用不同的方法。下面的代码是一个独立的应用程序，只需要在同一目录中的 jaas.conf 配置文件。
显示了用于此简短测试应用程序的示例 jaas.conf：
primaryLoginContext {
com.sun.security.auth.module.Krb5LoginModule required
useTicketCache=false
refreshKrb5Config=true
debug=false;
};
此代码小心设置系统属性 sun.net.inetaddr.ttl 以避免 java 缓存 DNS 查找的结果。就我而言，DNS 查找在每次请求时都会发生变化。这是一段相当粗糙的代码，但会演示网络中任何配置不当或性能不佳的 KDC。
import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStreamReader;
import java.math.BigDecimal;
import java.math.RoundingMode;
import java.net.InetAddress;
import java.net.MalformedURLException;
import java.net.UnknownHostException;
import java.util.Date;
import java.util.HashMap;
import java.util.Set;
import java.util.Vector;
import javax.security.auth.callback.Callback;
import javax.security.auth.callback.CallbackHandler;
import javax.security.auth.callback.NameCallback;
import javax.security.auth.callback.PasswordCallback;
import javax.security.auth.callback.UnsupportedCallbackException;
import javax.security.auth.login.LoginContext;
public class TestNadex {
private static final String DEFAULT_HOST = "cymru.nhs.uk";
public static void main(String[] args) {
System.setProperty("sun.net.inetaddr.ttl", "0");
String username=null;
String password=null;
try {
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
System.out.println("Enter username: ");
username = br.readLine().trim();
System.out.println("Enter password: ");
password = br.readLine().trim();
testHost(DEFAULT_HOST, username, password);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
static void testHost(String host, String username, String password) {
HashMap<String, Vector<Long>> results = new HashMap<String, Vector<Long>>();
for (int i=0; i<200; i++) {
InetAddress ia;
try {
ia = InetAddress.getByName(host);
long startTime = System.currentTimeMillis();
executePerformLogin(ia.getHostAddress(), username, password);
long endTime = System.currentTimeMillis();
long duration = endTime - startTime;
if (results.containsKey(ia.toString()) == false) {
Vector<Long> v = new Vector<Long>();
v.add(duration);
results.put(ia.toString(), v);
}
else {
Vector<Long> v = results.get(ia.toString());
v.add(duration);
}
Thread.sleep(1000);
} catch (UnknownHostException e) {
System.out.println("Unknown host: " + host);
System.exit(1);
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
Set<String> keys = results.keySet();
for (String key : keys) {
System.out.println("For address: " + key);
Vector<Long> times = results.get(key);
int count = times.size();
long total = 0;
for (Long t : times) {
System.out.println(t + " milliseconds");
total += t;
}
System.out.println("Mean duration: " + new BigDecimal(total).divide(new BigDecimal(count), RoundingMode.HALF_UP));
}
}
static void executePerformLogin(String hostname, String username, String password) throws MalformedURLException {
System.setProperty("java.security.krb5.realm", "CYMRU.NHS.UK");
System.setProperty("java.security.krb5.kdc", hostname);
File jaas = new File("jaas.conf");
String jaasconf = jaas.toURI().toURL().toExternalForm();
System.setProperty("java.security.auth.login.config", jaasconf);
// System.setProperty("java.security.krb5.realm", "cymru.nhs.uk");
// System.setProperty("java.security.krb5.kdc", "cymru.nhs.uk");
try {
System.out.println("Performing NADEX login for username: " + username + " at " + new Date() + " to server " + hostname);
LoginContext lc = new LoginContext("primaryLoginContext", new UserNamePasswordCallbackHandler(username, password));
lc.login();
System.out.println("Successful login for " + lc.getSubject().toString() + " at " + new Date());
}
catch (javax.security.auth.login.LoginException le) {
System.err.println("Failed to login: " + le);
}
}
public static class UserNamePasswordCallbackHandler implements CallbackHandler {
private final String _userName;
private final String _password;
public UserNamePasswordCallbackHandler(String userName, String password) {
_userName = userName;
_password = password;
}
public void handle(Callback[] callbacks) throws IOException,
UnsupportedCallbackException {
for (Callback callback : callbacks) {
if (callback instanceof NameCallback && _userName != null) {
((NameCallback) callback).setName(_userName);
}
else if (callback instanceof PasswordCallback && _password != null) {
((PasswordCallback) callback).setPassword(_password.toCharArray());
}
}
}
}
}