### Question:
HiveExpressions { static String toPartitionFilterString(Expression expr) { return ExpressionVisitors.visit(expr, ExpressionToPartitionFilterString.get()); } private  HiveExpressions();   }### Answer:
@Test public void testToPartitionFilterStringEscapeStringLiterals() { Expression input = equal("pcol", "s'1"); Assert.assertEquals("( pcol = 's\\'1' )", toPartitionFilterString(input)); }