Continuous Development Blog

Append Method handler

Another dynamic query builder. But this one , use simple StringBuilder instead of trying to parse the argument.  So more fast and adjustable dynamic query builder

For more see test cases and example dao

   @YMethod(type = YMethodType.APPEND,select = "pbyte,count(id)",groupBy = "pbyte")
    List<SimpleBean> append2(@YParameter("pint>=?") int i);

    @YMethod(type = YMethodType.APPEND,select = "pbyte,count(id)",groupBy = "pbyte",having = "count(id)>10")
    List<SimpleBean> append3(@YParameter("pint>=?") int i);

group and having support with aggregation support

Append and JPA criteria methods now support Projections

Execute Method handler

bulk method support

   @YMethod(type = YMethodType.EXECUTE,query = "update SimpleBean set pint=:newInt where id=:id ")
    int execute1(@YParameter(value = "newInt") int newInt,@YParameter(value = "id") long id);

experimental criteria query parser for JPA

Criteria method is now support more sophisticated queries . please see test cases and example dao

    @YMethod(type = YMethodType.CRITERIA)
    SearchResultList<SimpleBean> criteria2(@YParameter("pint >=") Integer arg1,@YParameter("pint <=") Integer arg2);

    @YMethod(type = YMethodType.CRITERIA)
    SearchResultList<SimpleBean> criteria3(@YParameter("pstring is null") boolean apply);

    @YMethod(type = YMethodType.CRITERIA)
    SearchResultList<Object> criteria2CheckApplied(@YParameter("pint>=20000") boolean apply1,@YParameter( "pint<=50000") boolean apply2);

quick code snippet to get the identifier field name for a given entity class from both hibernate and JPA 2.0 APIs.

for hibernate

public String getIdProperty(Class entityClass) {
String idProperty=sessionAccessor.getSessionFactory()
                                              .getClassMetadata(entityClass)
                                              .getIdentifierPropertyName();
return idProperty;
}

for JPA 2.0 metamodel API this method or to get value of id field see comment below

public String getIdProperty(Class entityClass) {
        String idProperty;
        Metamodel metamodel = getEntityManager().getMetamodel();
        EntityType entity = metamodel.entity(entityClass);
        Set<SingularAttribute> singularAttributes = entity.getSingularAttributes();
        for (SingularAttribute singularAttribute : singularAttributes) {
            if (singularAttribute.isId()){
                idProperty=singularAttribute.getName();
                break;
            }
        }
        if(idProperty==null)
            throw new RuntimeException("id field not found");
        return idProperty;
    }

to

A small tip to generate more meaningful Id. Instead of 32 for OrderID use O000000032.

Use smart and meaningful ids

Simple implementations:

• SmartIdTableGenerator
• SmartIdSequenceGenerator

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It has been more than a week since I downloaded Grails, Although my first Grails impressions are not so well, I am playing with Grails with lots of curiosity and joy, Read more