String test = "1";
String test2 = "2";
Map map = ["test":test, "test2":test2];
String txt = 'WHERE oid_2 = $$test$$ || oid_2 = $$test2$$';
print txt.replaceAll(/\$\$(.*?)\$\$/) { k -> map[k[1]] ?: k[0] }
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