private ShaderCallback callback = new ShaderCallBack() {
    @Override
    public void call(int shader) {
        int texUniform = ARBShaderObjects.glGetUniformLocationARB(shader, "tex");
        int colorUniform = ARBShaderObjects.glGetUniformLocationARB(shader, "color");

        ARBShaderObjects.glUniform1iARB(texUniform, 0);
        ARBShaderObjects.glUniform3fARB(colorUniform, colorR, colorG, colorB);
    }
}