GameState splash;
GameState title;
GameState play;

gameLoop.state = splash;

gameLoop.update(time);  // calls gameLoop.state.update()
gameLoop.render(surface); // calls gameLoop.state.render()

string GameState;

switch (GameState)
{
    case: "MainMenu"
    ExecuteMainMenuLoop();
    break;

    case: "MainGameLoop"
    ExecuteMainGameLoop();
    break;
}

// Java
// Note: Syntax probably not 100% correct; been a LONG time since I've seriously used Java.

public class GameState {
    // declare variables necessary to the state
    // examples: Menu choices; input handlers; etc.

    public function update(time) {
        // update the objects in this state
        // examples: animated sprites, timed effects
    }

    public function render(surface) {
        // draw to the screen/buffer
    }

    // other functions for the class. Suggestions include "initialize", "pause", etc.
}

// Then, when setting the game up, initialize your states...
GameState_Splash splash = new GameState_Splash();    // in real life, the variables would be extended from the GameState class
GameState_Title title = new GameState_Title();
GameState_Play play = new GameState_Play();

GameLoop mainLoop = new GameLoop();
mainLoop.setState(splash);    // let's start with the splash state, like most people do
mainLoop.run();    // start the loop

// .....

// In the game loop...

public function setState(GameState state) {
    this.state = state;
}

public function update(time) {
    this.state.update(time);
}

public function render(surface) {
    this.state.render(surface);
}

virtual ~GameState()

GameStateSplash::GameStateSplash() : GameState() { ... }