Get login username in java
System.getProperty("user.name") is not a good security option since that environment variable could be faked: C:\ set USERNAME="Joe Doe" java ... // will give you System.getProperty("user.name") You ought to do:
com.sun.security.auth.module.NTSystem NTSystem = new com.sun.security.auth.module.NTSystem();
System.out.println(NTSystem.getName());
JDK 1.5 and greater.
I use it within an applet, and it has to be signed. info source
inspired by @newacct's answer, a code that can be compiled in any platform:
String osName = System.getProperty( "os.name" ).toLowerCase();
String className = null;
String methodName = "getUsername";
if( osName.contains( "windows" ) ){
className = "com.sun.security.auth.module.NTSystem";
methodName = "getName";
}
else if( osName.contains( "linux" ) ){
className = "com.sun.security.auth.module.UnixSystem";
}
else if( osName.contains( "solaris" ) || osName.contains( "sunos" ) ){
className = "com.sun.security.auth.module.SolarisSystem";
}
if( className != null ){
Class<?> c = Class.forName( className );
Method method = c.getDeclaredMethod( methodName );
Object o = c.newInstance();
System.out.println( method.invoke( o ) );
}
System.getProperty("user.name");
in Unix:
new com.sun.security.auth.module.UnixSystem().getUsername()
in Windows:
new com.sun.security.auth.module.NTSystem().getName()
in Solaris:
new com.sun.security.auth.module.SolarisSystem().getUsername()