Annotation Type DtoConverters

@Target({PACKAGE,MODULE}) @Retention(CLASS) public @interface DtoConverters
Register one or more types whose public conversion methods should be applied automatically, by exact (source type, target type) match, to any DTO property with no explicit per-property DtoConvert.

Used with generated entity-to-DTO graph mapping (see query.mapTo(SomeDto.class)). Declared on a neutral holder - typically a package-info.java - the same convention as DtoMapping.

@DtoConvert alone requires repeating the same annotation on every property that needs the same conversion - tedious when one conversion (e.g. Instant -> Calendar, or an enum <-> String) recurs across many otherwise-unrelated properties on a target. Rather than annotate each property individually, register the class(es) declaring those conversions once: 

@DtoConverters({DateConversions.class, EnumConversions.class})
package org.example.dto;
Every public, single-parameter, non-void-returning method declared directly on a registered type is indexed by its exact parameter type and return type. Whenever a DTO property's resolved source value type doesn't already exactly match the target property's type, and that property carries no explicit DtoConvert, the generator looks up the (source type, target type) pair in this index and wires the matching method in automatically - dispatched the same way as DtoConvert (a direct static call for a static method, or an instance resolved via io.ebean.DtoConverterManager for an instance method needing a real dependency).

Matching is by exact type equality on both the parameter and return type - no widening/supertype matching - so which method applies (if any) stays fully predictable. An explicit per-property DtoConvert always takes precedence and is never overridden by a type-pair default. Ebean itself ships no built-in conversions (e.g. no implicit Enum.valueOf/.name()) - the registered method fully owns its own semantics (e.g. returning null rather than throwing on an unrecognised enum value).

This is purely a compile-time / codegen-time hint - it carries no runtime footprint (source retention).

  • Required Element Summary

    Required Elements
    Modifier and Type
    Required Element
    Description
    Class<?>[]
    value
    The type(s) declaring conversion methods to index by (parameter type, return type) - an arbitrary app-defined shape, no ebean-mandated interface.

  • Element Details

    • value

      Class<?>[] value
      The type(s) declaring conversion methods to index by (parameter type, return type) - an arbitrary app-defined shape, no ebean-mandated interface.