Then he showed me the river of the water of life, bright as crystal, flowing from the throne of God and of the Lamb through the middle of the street of the city [the new Jerusalem]; also, on either side of the river, the Tree of Life... Blessed are those who wash their robes, that they may have the right to the Tree of Life and that they may enter the city by the gates. Outside are the dogs and sorcerers and fornicators and murderers and idolaters, and every one who loves and practices falsehood (Revelation 22:1-2, 14-15)
There you have it, in black and white! Even the Greek is clear: Outside are "the dogs" (kunes). The Heavenly Jerusalem has a sign, and it reads: "No Dogs allowed." So, for all you dog-lovers, sorry.