Question

I have a Java class which has some field annotated with @SearchCriteria(criteria = "class1.class2.field"). criteria parameter inside annotation means for with class this field should be set as hibernate criteria, it mean that, if field marked for example:

@SearchCriteria(criteria = "class1.class2.field")
private String value;

I want dynamicly create hibernate criteria with looks like

DetachedCriteria hibernateCriteria = forClass(Class.class);
hibernateCriteria.createCriteria("class1").createCriteria("class2").add(eq("field", value));

Problem is than I can not set another criteria to already added, it mean I should check annotation criteria option.

      switch (annotationCriteria.length - 1) {
case 0:             
hibernateCriteria.add(isNull(annotationCriteria[0]));               
case 1:
hibernateCriteria.createCriteria(annotationCriteria[0]).add(                Restrictions.isNull(annotationCriteria[annotationCriteria.length - 1]));
case 2:   hibernateCriteria.createCriteria(annotationCriteria[0]).createCriteria(annotationCriteria[1]).add(                Restrictions.isNull(annotationCriteria[annotationCriteria.length - 1]));
    }

I want to remove this “swith”. It is possible to get already added criteria by, I dont now, for example by “name” and that add new subcriteria for it.

Answer 1

I find out more “nice” solution for this issue.
First of all create some searchCriteria class, for example:

public class SearchCriteria {

    @SearchCriteria(path = "someclass.someclass.id")
    private Integer someId;

    public Integer getSomeId() {
        return someId;
    }

    public void setSomeId(Integer someId) {
        this.someId= someId;
    }
}

And custom annotation:

@Target(value = { ElementType.FIELD })
@Retention(RUNTIME)
public @interface SearchCriteria {
    String path() default "";

    boolean optional() default true;
}

And in DAO class:

@Override
    public Collection<SomeClass> find(SearchCriteria criteria) {
        DetachedCriteria hibernateCriteria = forClass(SomeClass.class);

        for (Field field : criteria.getClass().getDeclaredFields()) {
            Annotation annotation = field.getAnnotation(SearchCriteria.class);

            if (annotation == null) {
                continue;
            }

            List<String> elements = Arrays.asList(StringUtils.split(((SearchCriteria) annotation).path(), "."));

            field.setAccessible(true);
            Object fieldValue = null;
            try {
                fieldValue = field.get(criteria);
            } catch (IllegalArgumentException e) {
                LOG.error("while trying to get private field value of entity " + SearchCriteria.class, e);
            } catch (IllegalAccessException e) {
                LOG.error("while trying to get private field value of entity " + SearchCriteria.class, e);
            }

            for (String element : elements) {
                if (elements.indexOf(element) == elements.size() - 1) {
                    hibernateCriteria = hibernateCriteria.add(eq(element, fieldValue));
                } else {
                    hibernateCriteria = hibernateCriteria.createCriteria(element);
                }
            }
        }

        return getHibernateTemplate().findByCriteria(hibernateCriteria);
    }