How to implement the json function with 1.5.2?

[renwairen]

Hi:
I want to extend some json function, such as "xxx MEMBER OF (json_column)".
When I use 1.5.0，I can do like this:

    class IsMemberOf extends AbstractSingleValueCondition<String> {
            @Override
            public String renderCondition(String columnName, String placeholder) {
                return columnName + " MEMBER OF (" + super.value + ")"; 
            }
        }

But with 1.5.2, it's not easy to do so, how can I implement this function?

[jeffgbutler]

tl;dr - do this (longer explanation in the next comment)

public class MemberOfCondition<T> extends AbstractNoValueCondition<T> {
    private final String jsonArray;

    protected MemberOfCondition(String jsonArray) {
        this.jsonArray = Objects.requireNonNull(jsonArray);
    }

    @Override
    public String operator() {
        return "member of(" + jsonArray + ")";
    }

    public static <T> MemberOfCondition<T> memberOf(String jsonArray) {
        return new MemberOfCondition<>(jsonArray);
    }
}

[jeffgbutler]

(Longer explanation)
This changed in version 1.5.1 - there was a major refactoring of rendering in that release.

I've been experimenting with "member of" and it is a bit odd. In the way this DSL is built we would consider it as either a function or an condition depending on how you want the syntax to work. For example...

select(foo.allColumns())
.from(foo)
.where(id, memberOf("'[1, 2, 3]'")

// (condition mode) renders as...   select * from foo where id member of('[1, 2, 3]')

select(foo.allColumns())
.from(foo)
.where(memberOf(id, "'[1, 2, 3]'"), isEqualTo(1L))

// (function mode) renders as...  select * from foo where id member of('[1, 2, 3]') = 1

Of course, you could implement both and use it either way. Here's how I would do it as a condition:

public class MemberOfCondition<T> extends AbstractNoValueCondition<T> {
    private final String jsonArray;

    protected MemberOfCondition(String jsonArray) {
        this.jsonArray = Objects.requireNonNull(jsonArray);
    }

    @Override
    public String operator() {
        return "member of(" + jsonArray + ")";
    }

    public static <T> MemberOfCondition<T> memberOf(String jsonArray) {
        return new MemberOfCondition<>(jsonArray);
    }
}

Here's how I would do it as a function:

public class MemberOfFunction<T> extends AbstractTypeConvertingFunction<T, Long, MemberOfFunction<T>> {

    private final String jsonArray;

    protected MemberOfFunction(BasicColumn column, String jsonArray) {
        super(column);
        this.jsonArray = Objects.requireNonNull(jsonArray);
    }

    @Override
    protected MemberOfFunction<T> copy() {
        return new MemberOfFunction<>(column, jsonArray);
    }

    @Override
    public FragmentAndParameters render(RenderingContext renderingContext) {
        return column.render(renderingContext)
                .mapFragment(f -> f + " member of(" + jsonArray + ")");
    }

    public static <T> MemberOfFunction<T> memberOf(BindableColumn<T> column, String jsonArray) {
        return new MemberOfFunction<>(column, jsonArray);
    }
}

In the "function" mode, you could also include it in a select list like this:

select(id, memberOf(id, "'[1, 2, 3]'").as("inTheList"))
.from(foo)

// (function mode) renders as...  select id, id member of('[1, 2, 3]') as inTheList from foo

[renwairen]

Ok, thank your for the example, I will try it.