public void compileShader() {
        glLinkProgram(program);

        if (glGetProgram(program, GL_LINK_STATUS) == 0) {
            System.err.println(glGetProgramInfoLog(program, 1024));
            System.exit(1);
        }

        glValidateProgram(program);

        if (glGetProgram(program, GL_VALIDATE_STATUS) == 0) {
            System.err.println(glGetProgramInfoLog(program, 1024));
            System.exit(1);
        }
    }