How does the voice of the nightingale affect the poet in "Ode to a Nightingale"?

In "Ode to a Nightingale," the Romantic poet John Keats is transported through a myriad of emotions by the song of the nightingale. In the first stanza, he feels such ecstasy that his emotions leave him feeling as if he had been drugged, and the awe of the sensation is akin to a sense of anguish. In the second stanza he feels a timeless sense of joy and a oneness with nature, to the point that he can feel the beauty of the countryside and taste the fruit of the vine that the warmth and sunshine produce.
The mood changes with the third stanza, as the nightingale song makes him realize how different human life is from the transporting beauty of the song. Here he feels sadness and despair about the fading of youth and sorrows of old age and loss of love. At this point he feels it best to die while in the throes of the intoxicating song.
While the nightingale’s song will continue on for generations to come, as it was for generations past, he realizes he will hear it no more after death. Keats is now affected by the song with the melancholy realization that it was for him a fleeting moment of transcendence, but that the song of the nightingale will go on forever.