Java: Serializing String[] Array to store in a MySQL Database?

Question

Yes, I know it's bad practice and I should instead normalize my tables. That put aside, is it possible to serialize a String [] array and store it in the database?

I am from the lenient and forgiving world of PHP, where invoking the serialize() function and would convert the array into a string.

Is there an equivalent of doing such heresy in Java? Apart from normalization, are there more elegant ways of storing String Arrays in the database?

In case it's applicable, I am using the jdbc driver for my MySQL connections.

Answer 1

Yes. You can serialize any Java objects and store the serialized data into MySQL.

If you use the regular serialization (ObjectOutputStream), the output is always binary. Even String is serialized into binary data. So you have to Base64 encode the stream or use a binary column like BLOB.

This is different from PHP, whose serialize() converts everything into text.

You can also use the XML serialization in Java (XMLEncoder) but it's very verbose.

Answer 2

If you're thinking in terms of raw arrays, you're still writing PHP in Java.

Java's an object-oriented language. An array of Strings really isn't much of an abstraction.

You'll get perfectly good advice here telling you that it's possible to serialize that array of Strings into a BLOB that you can readily store in MySQL, and you can tell yourself that leniency is a virtue.

But I'll going to remind you that you're losing something by not thinking in terms of objects. They're really about abstraction and encapsulation and dealing with things at a higher level than bare metal ints, Strings, and arrays.

It'd be a good exercise to try and design an object that might encapsulate an array or another more sophisticated data structure of child objects that were more than Strings. There'd be a 1:m relationship between parent and child that would better reflect the problem you were really trying to solve. That would be a far more object-oriented design than the one you're proposing here.