Gaurab Paul

Polyglot software developer & consultant passionate about web development, distributed systems and open source technologies

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Adapting jOOQ code generator to Rails database naming conventions
Posted  a year ago

I recently updated an application which was historically built using Ruby on Rails to Spring boot & jOOQ.

The Rails convention is to use plural table names (eg. users) which are auto-mapped to models with singular names (eg. User).

JOOQ doesn't do any automatic plural->singular conversion by default, so if we directly use code-generator we end up with pojos named like class Users and interfaces like interface IUsers which are not ideal because an instance here represents a single entity/row and so should be named singular.

Fortunately this is easy to address with a custom NamingStrategy:

package com.example;

import org.jibx.schema.codegen.extend.DefaultNameConverter;
import org.jibx.schema.codegen.extend.NameConverter;
import org.jooq.codegen.DefaultGeneratorStrategy;
import org.jooq.meta.Definition;

public class NamingStrategy extends DefaultGeneratorStrategy {

    private final NameConverter nameTools = new DefaultNameConverter();

    public String getJavaClassName(final Definition definition, final Mode mode) {
        final String javaClassName = super.getJavaClassName(definition, mode);

        // Let's retain the plural names for TableImpl clasess
        if (mode == Mode.DEFAULT) return javaClassName;

        // Let's use singular names for others
        return nameTools.depluralize(javaClassName);


Support for custom GeneratorStrategy implementations in JooQ offers possibility of very low level customizations of how SQL layer names are translated to java/kotlin layer.

In our case, we simply use the depluralize utility from jibx to singularize our names.

We can configure our JooQ configuration to use this naming strategy:

<!-- Other configuration options -->