如何使用JOOQ Model API从基于字符串的列名添加动态条件？

Question

I am using the JOOQ Model API to dynamically build a query. It is similar to what is being asked here :

However, I need this query to have dynamic conditions based on columns names and values I am passing in as Strings. I know in my repository what the table is from a private getTable() method.

String fieldName = "my_column";
String fieldValue = "searchTerm";

SelectQuery<Record> query = create.selectQuery();
query.addFrom(getTable());

Instead of doing something like this...

query.addConditions(BOOK.TITLE.like(fieldValue + "%")); 

I need a generalized way to get table fields by name...

query.addConditions(getTable().getTableField(fieldName).like(fieldValue + "%"));

I couldn't find anything on the generated table or record classes that did this. The table class has the TableField static members I need to use, but no way to look them up by name. Is there something else available I am missing?

If not, I see two courses of action. I prefer the first:

1. Customize the generator somehow to create some kind of internal lookup on the generated Table class.

2. I could create new TableFieldImpl instances, but that seems like a waste when generated TableImpl classes already have them and I would need to know everything about the table column in order to create it properly.

EDIT: I think what I want may be DSL.condition() which can take a SQL string and bound parameters or you can create a condition like this:

query.addConditions(DSL.condition("? = ?", fieldName,fieldValue));

Answer 1

The method you're looking for is called TableLike.field(String) and it is thus present on all table expressions in the jOOQ API. For instance:

query.addConditions(getTable().field(fieldName).like(fieldValue + "%"));

Now, this won't work out of the box, because the Field<?> reference's wildcard will prevent you from comparing that Field with fieldValue + "%" . You have these options:

jOOQ 3.5 and less

getTable().field(fieldName).coerce(String.class).like(fieldValue + "%")
((Field<String>) getTable().field(fieldName)).like(fieldValue + "%")

jOOQ 3.6

getTable().field(fieldName, String.class).like(fieldValue + "%")