Texture not rendering when using shaders?

I am currently testing something out with GLSL, but now whenever I use shaders, my texture doesn't show up on the screen. I have 2 classes. It works without the shaders though...

Main Class

public class Main {

    private static final int WIDTH = 1280;
    private static final int HEIGHT = 720;
    private static int shaderProgram;

    private static int vertexShader;
    private static int fragmentShader;

    private static Terrain terrain;

    public static void main(String[] args) {


        initDisplay();
        initGL();

        terrain = new Terrain();
        terrain.createTerrain();

        createShader();

        gameLoop();

        removeShader();

    }

    private static void gameLoop() {
        while (!Display.isCloseRequested()) {
            glClear(GL_COLOR_BUFFER_BIT);
            glUseProgram(shaderProgram);

            terrain.drawTerrain();
            glUseProgram(0);


            Display.update();
            Display.sync(60);

        }
    }

    private static void initGL() {
        glMatrixMode(GL_PROJECTION);

        glLoadIdentity();

        glOrtho(0, WIDTH, 0, HEIGHT, -1, 1);

        glMatrixMode(GL_MODELVIEW);

        glDisable(GL_DEPTH_TEST);
        glEnable(GL_TEXTURE_2D);

        glClearColor(0, 0, 0, 1);
    }

    private static void initDisplay() {
        try {
            Display.setDisplayMode(new DisplayMode(WIDTH, HEIGHT));
            Display.create();

        } catch (LWJGLException e) {
            e.printStackTrace();
        }
    }

    private static void createShader() {
        shaderProgram = glCreateProgram();
        vertexShader = glCreateShader(GL_VERTEX_SHADER);
        fragmentShader = glCreateShader(GL_FRAGMENT_SHADER);
        StringBuilder vertexShaderSource = new StringBuilder();
        StringBuilder fragmentShaderSource = new StringBuilder();
        try {
            BufferedReader reader = new BufferedReader(new FileReader("src/me/mateo226/shaders/vertexShader.txt"));
            String line;
            while ((line = reader.readLine()) != null) {
                vertexShaderSource.append(line).append("\n");
            }
            reader.close();
        } catch (IOException e) {
            System.err.println("Vertex shader wasn't loaded properly!");
            Display.destroy();
            System.exit(1);
        }
        try {
            BufferedReader reader = new BufferedReader(new FileReader("src/me/mateo226/shaders/fragmentShader.txt"));
            String line;
            while ((line = reader.readLine()) != null) {
                fragmentShaderSource.append(line).append("\n");
            }
            reader.close();
        } catch (IOException e) {
            System.err.println("Fragment shader wasn't loaded properly!");
            Display.destroy();
            System.exit(1);
        }

        glShaderSource(vertexShader, vertexShaderSource);
        glCompileShader(vertexShader);
        if (glGetShader(vertexShader, GL_COMPILE_STATUS) == GL_FALSE) {
            System.err.println("Vertex shader not compiled!");
        }
        glShaderSource(fragmentShader, fragmentShaderSource);
        glCompileShader(fragmentShader);
        if (glGetShader(fragmentShader, GL_COMPILE_STATUS) == GL_FALSE) {
            System.err.println("Fragment shader not compiled!");
        }

        glAttachShader(shaderProgram, vertexShader);
        glAttachShader(shaderProgram, fragmentShader);
        glLinkProgram(shaderProgram);
        glValidateProgram(shaderProgram);
    }

    private static void removeShader() {

        glDeleteProgram(shaderProgram);
        glDeleteShader(vertexShader);
        glDeleteShader(fragmentShader);
        Display.destroy();
    }

}

Terrain Class

public class Terrain {
    private static List<Tile> tiles = new ArrayList<Tile>();

    public Terrain() {

    }

    public void createTerrain() {
        Random rand = new Random();
        for (int i = 0; i < 20; i++) {
            for (int j = 0; j < 15; j++) {
                int r = rand.nextInt(2);
                tiles.add(new Tile(i * 64, j * 64, r));
            }
        }
    }

    public void drawTerrain() {
        for (Tile t : tiles) {
            t.draw();
        }
    }

}

class Tile {

    int type = 0;

    private float x = 0;
    private float y = 0;
    private float width = 64;
    private float height = 64;

    private Texture tex;

    public Tile(float x, float y, int type) {
        this.type = type;
        this.x = x;
        this.y = y;
        try {
            if (this.type == 1) {
                tex = TextureLoader.getTexture("PNG", new FileInputStream(new File("res/grass.png")));
            } else {
                tex = TextureLoader.getTexture("PNG", new FileInputStream(new File("res/grass.png")));
            }
        } catch (FileNotFoundException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

    public void draw() {
        tex.bind();
        glBegin(GL_QUADS);
        {
            glTexCoord2f(0, 0);
            glVertex2f(x, y);
            glTexCoord2f(0, 1);
            glVertex2f(x, y + height);
            glTexCoord2f(1, 1);
            glVertex2f(x + width, y + height);
            glTexCoord2f(1, 0);
            glVertex2f(x + width, y);
        }
        glEnd();
    }

}

While it may seem like a lot of code, it really isn't, just a simple program. However I am still unable to figure out what makes it not work. My vertex shader just has:

gl_Position = ftransform();

I tried adding gl_FragColor to the fragment shader but it doesn't help. Cheers!