Do you mean by Hamas firing missiles at Sderot and the surrounding Gaza Jewish Areas in order to cause Israelis to move away from the Gaza border. Or when the Israeli Arab towns won't allow Jews to move in. Or Palestine calling for all the Jews to be removed from their territory when Palestine is finally created?
Ethnic cleansing, as defined by the UN: "the planned deliberate removal from a specific territory, persons of a particular ethnic group, by force or intimidation, in order to render that area ethnically homogenous."
Hamas firing missiles is terrorism and/or an act of war, not ethnic cleansing.
Israeli Arab towns not allowing Jews to move in (and likewise, Jewish towns not allowing Arabs to move in) is not in and of itself "ethnic cleansing" either.
If Palestine acted upon their call for all the Jews to be removed from their territory when Palestine is finally created - it would indeed be ethnic cleansing. But, how about sticking to the actual instead of theoretical?