What does Ecclesiastes 2:5 mean?

I said of laughter, “It is foolishness”; and of mirth, “What does it accomplish?”

I searched in my heart how to cheer my flesh with wine, my heart yet guiding me with wisdom, and how to lay hold of folly, until I might see what it was good for the sons of men that they should do under heaven all the days of their lives.

I made myself great works. I built myself houses. I planted myself vineyards.

I made myself pools of water, to water from it the forest where trees were reared.

I bought male servants and female servants, and had servants born in my house. I also had great possessions of herds and flocks, above all who were before me in Jerusalem;

I also gathered silver and gold for myself, and the treasure of kings and of the provinces. I got myself male and female singers, and the delights of the sons of men—musical instruments, and that of all sorts.