e508. getting the login name of the currently logged-in user.txt

这里面包含了一百多个JAVA源文件

This example retrieves the login name of the user that is running the application. 
    try {
        String loginAppName = "GetLoginNameUnix";
    
        // If the application is run on NT rather than Unix, use this name
        loginAppName = "GetLoginNameNT";
    
        // Create login context
        LoginContext lc = new LoginContext(loginAppName,
            new com.sun.security.auth.callback.TextCallbackHandler());
    
        // Retrieve the information on the logged-in user
        lc.login();
    
        // Get the authenticated subject
        Subject subject = lc.getSubject();
    
        // Get the subject principals
        Principal principals[] = (Principal[])subject.getPrincipals().toArray(new Principal[0]);
        for (int i=0; i<principals.length; i++) {
            if (principals[i] instanceof com.sun.security.auth.NTUserPrincipal
                  || principals[i] instanceof com.sun.security.auth.UnixPrincipal) {
                String loggedInUserName = principals[i].getName();
            }
        }
    } catch (LoginException e) {
        // Login failed
    }

The example requires a login configuration file that specifies the login modules to execute when using a particular login-app name. This configuration file specifies two login-app names: 
    GetLoginNameNT {
        com.sun.security.auth.module.NTLoginModule required;
    };
    
    GetLoginNameUnix {
        com.sun.security.auth.module.UnixLoginModule required;
    };

The login configuration file is specified at the command line: 
    > java -Djava.security.auth.login.config=myconfig.config MyApp