Expression expression = Expression.comparison("columnName1", "qualifier1", Comparison.Operator.EQ, Bytes.toBytes("value"));
DataOutputBuffer dataOutputBuffer = new DataOutputBuffer();
WritableHelper.writeInstanceNullable(dataOutputBuffer, expression);
DataInputBuffer dataInputBuffer = new DataInputBuffer();
dataInputBuffer.reset(dataOutputBuffer.getData(), dataOutputBuffer.getLength());
Expression clonedExpression = WritableHelper.readInstanceNullable(dataInputBuffer, Expression.class);
Assert.assertEquals("The expression was not the same after being written and read", expression, clonedExpression);
}