How to Change a User’s Password via API (If the User Can Login)

Backendless.UserService.login( "spidey@backendless.com", "greeng0blin", new AsyncCallback<BackendlessUser>()
{
    @Override
    public void handleResponse( BackendlessUser user )
    {
       user.setPassword( "MyNewPassword" );
       Backendless.Data.of( BackendlessUser.class ).save( user, new AsyncCallback<BackendlessUser>()
       {
           @Override
           public void handleResponse( BackendlessUser backendlessUser )
           {
               System.out.println( "User password has been changed" );
           }
           @Override
           public void handleFault( BackendlessFault backendlessFault )
           {
               System.out.println( "Server reported an error - " + backendlessFault.getMessage() );
           }
       } );
    }
    @Override
    public void handleFault( BackendlessFault backendlessFault )
    {
        System.out.println( "Server reported an error - " + backendlessFault.getMessage() );
    }
} );

val user = Backendless.UserService.login("spidey@backendless.com", "greeng0blin")
user.password = "myNewPassword"
Backendless.Data.of(BackendlessUser::class.java).save(user, object : AsyncCallback {
   override fun handleResponse(response: BackendlessUser?) {
       Log.i(TAG, "User password has been changed")
   }

   override fun handleFault(fault: BackendlessFault?) {
       Log.e(TAG, fault?.message)
   }
})

[Backendless.shared.userService loginWithIdentity:@"spidey@backendless.com" password:@"greeng0blin" responseHandler:^(BackendlessUser *loggedInUser) {
    loggedInUser.password = @"MyNewPassword";
    [[Backendless.shared.data of:[BackendlessUser class]] updateWithEntity:loggedInUser responseHandler:^(BackendlessUser *updatedUser) {
        NSLog(@"User password has been changed");
    } errorHandler:^(Fault *fault) {
        NSLog(@"Error: %@", fault.message);
    }];
} errorHandler:^(Fault *fault) {
    NSLog(@"Error: %@", fault.message);
}];

Backendless.shared.userService.login(identity: "spidey@backendless.com", password: "greeng0blin", responseHandler: { loggedInUser in
    loggedInUser.password = "MyNewPassword"
    Backendless.shared.data.of(BackendlessUser.self).update(entity: loggedInUser, responseHandler: { updatedUser in
        print("User password has been changed")
    }, errorHandler: { fault in
        print("Error:\(fault.message ?? "")")
    })
}, errorHandler: { fault in
    print("Error:\(fault.message ?? "")")
})

const Backendless = require('backendless')
/*
 Or use `import Backendless from 'backendless'` for client side.
 If you don't use npm or yarn to install modules, you can add the following line
 <script src="//api.backendless.com/sdk/js/latest/backendless.min.js"></script>
 to your index.html file and use the global Backendless variable.
*/

Backendless.initApp('YOUR_APP_ID', 'YOUR_JS_API_KEY')

const onLoginSuccess = user => {
  user.password = 'MyNewPassword'

  return Backendless.UserService.update(user)
}

const onPasswordUpdateSuccess = user => {
  console.log('User password has been changed')
}

const onError = error => {
  console.error('Server reported an error: ', error.message)
  console.error('error code: ', error.code)
  console.error('http status: ', error.status)
}

Backendless.UserService.login('spidey@backendless.com', 'greeng0blin')
  .then(onLoginSuccess)
  .then(onPasswordUpdateSuccess)
  .catch(onError)

var user = await Backendless.UserService.login("spidey@backendless.com", "greeng0blin");
user.password = "MyNewPassword";
Backendless.Data.of("Users").save(user.toJson()).then((response) => print("User password has been changed"));