Concept code of ExternalDomain in Doma

DomainConverter.java

package org.seasar.doma.jdbc.domain;

public interface DomainConverter<D, V> {

    // Java to DB
    V fromDomainToValue(D domain);

    // DB to Java
    D fromValueToDomain(V value);
}

ExternalDomain.java

// Marker Annotation
package org.seasar.doma;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface ExternalDomain {
}

Memo.java

    public synchronized void init(ProcessingEnvironment processingEnv) {
        super.init(processingEnv);
        String csv = Options.getDomainConverters(processingEnv);
        List<TypeElement> converterTypeElements = new ArrayList<TypeElement>();
        if (csv != null) {
            for (String className : csv.split(",")) {
                if (!className.isEmpty()) {
                    TypeElement typeElement = ElementUtil.getTypeElement(
                            className, processingEnv);
                    if (typeElement != null) {
                        converterTypeElements.add(typeElement);
                    }
                }
            }
        }
        this.converterTypeElements = converterTypeElements;
    }

Salary.java

package example;

import java.math.BigDecimal;

public class Salary {

    public BigDecimal value;

    public Salary(BigDecimal value) {
        this.value = value;
    }
}

SalaryConverter.java

package example;

import java.math.BigDecimal;

import org.seasar.doma.ExternalDomain;
import org.seasar.doma.jdbc.domain.DomainConverter;

@ExternalDomain
public class SalaryConverter implements DomainConverter<Salary, BigDecimal> {

    @Override
    public BigDecimal fromDomainToValue(Salary domain) {
        return domain.value;
    }

    @Override
    public Salary fromValueToDomain(BigDecimal value) {
        return new Salary(value);
    }
}