What is a Deconstructionist reading of John Keats's poem "Ode on a Grecian Urn"?

Deconstructionist readings break down a text into its different parts and examine the questions or ambiguities posed by those different elements or parts. To carry out a deconstructionist reading, you should first locate a binary opposition, or where the text makes a distinction between two things. Then, analyze how something is described by comparison or by being different from something else in the text.
Keats's "Ode on a Grecian Urn" offers a very nice binary opposition between the world of art and the real world. In the first stanza, he starts by describing the frozen world on the urn with a picture of a "still unravish'd bride of quietness." He goes on to describe the pure woman on the urn and her ability to "express/ A flowery tale more sweetly than our rhyme." Then, he asks about this scene: "What men or gods are these? What maidens loth?/What mad pursuit? What struggle to escape? /What pipes and timbrels? What wild ecstasy?" In other words, he wonders what the reality of this scene is and who the people in the scene really are, but he does not answer his questions. 
In the second stanza, he praises the frozen world of the urn and its continual freshness. He writes, "Fair youth, beneath the trees, thou canst not leave/ Thy song, nor ever can those trees be bare." In the world of art, the youth remains forever young, and the trees always have leaves. As he writes in the third stanza, in the world of art, there is always "More happy love! more happy, happy love!" Love never fades in art, but, as he returns to the real world, he notes that passion is quite different than the way it is portrayed on the urn, as it "leaves a heart high-sorrowful and cloy'd, /A burning forehead, and a parching tongue." In other words, while the youth on the urn are forever happy and in love, in real life, love often leads to spent passion and unhappiness.
In the fourth stanza, Keats presents a number of questions, such as, "Who are these coming to the sacrifice?" He wonders who the people in the vase are, and where the priest is leading them. The series of questions he poses have no answers, and so he creates a sense of discomfort and mystery that he leaves the reader to answer. In the last stanza, he refers to the scene as a "Cold Pastoral! When old age shall this generation waste, Thou shalt remain." In other words, when he and his contemporaries are long gone, the world of the vase will remain, but he refers to this world as cold, without passion, and he leaves the reader to decide which member of the pair of binary opposites is better--art or the real world.
Sources:
Mishra, Prashant. “A Deconstructive Stylistic Reading of Keats’ Ode on a Grecian Urn.” The Southeast Asian Journal of English Language Studies 17.2: 49-58. 
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