The Bible refers to the fruit of the Spirit in Galatians 5:22 and Ephesians 5:9. The fruit is singular, because however manifold it is, it refers to one harmonious whole. It is "fruit" in contrast with the sinful acts of mankind which are called "works of the flesh."
The manifestations of the Spirit are called fruit because they make one fruitful in the eyes of God.
One aspect of the fruit of the Spirit is joy. Being joyful because of worldly pleasure is not what joy from the Spirit is about.
Joy is often a lost cause. The physical things we are engaged in produce almost as much negative emotions as positive. Many people have as many feelings of despair and futility as joy. In contrast, things of God are all positive for the obedient.
The fruit of the Spirit refers to the qualities that the Spirit of God produces in believers. It comes from learning the ways of God and acting on them.
Jesus indicated that when you do what he tells you in the New Testament, you will be blessed and joyful (John 13:17) Do you see how it works? When you act on your faith, he gives you joy. There is a special connection with the Lord when you do for him what you love to do.
He gave you a unique ability and when you use it for his cause, he gives you joy.
The disciples of Christ were spoken of as full of joy in the Holy Spirit in Scripture (Acts 13:52). This is a bonus for being in Christ. You may find some joy in physical things, but it cannot compare with what God has prepared for the obedient. We are not to glory in riches or wisdom, but in the fact that we know God, because he acts with steadfast love, justice and righteousness
Jesus said, "I have said these things to you so that my joy may be in you, and that your joy may be complete" (First John 15:11).
In Bible days when people obeyed God and realized their sins were forgiven and they would have a home in heaven, they leaped for joy and praised God. You may feel too sophisticated for an outward show of emotion, but you can at least have joy in your heart that your name is written in the book of life.
If you are not a Christian, you know nothing of the fruit or gifts of the Spirit. Those who are unspiritual do not receive the gifts of the Spirit. They are foolishness to him. They are unable to understand them. They are spiritually discerned. To obtain them you must repent of your sins, confess Jesus as the son of God, and be baptized for the remission of your sins. You will then receive the gift of the Holy Spirit.