everyone.
Sorry for some english mistakes.
I am using Vaadin to build a front-end search interface for some search tasks.
In front-end I have only one text field called "telefone" that should fill three fields in my entity bean (telefone1, telefone2 and telefone3), because the telephone number provided by user can be found in any "telefone" field. See the code below:
#SuppressWarnings("unchecked")
#Override
public List<Fornecedor> executaPesquisaAvancadaDeFornecedores(Fornecedor fornecedor) {
Map<Integer, Fornecedor> fornecedoresMap = new HashMap<Integer, Fornecedor>();
if(fornecedor.getTelefone1() != null) fornecedor.setTelefone1("%" + fornecedor.getTelefone1() + "%");
fornecedor.setTelefone2(fornecedor.getTelefone1());
fornecedor.setTelefone3(fornecedor.getTelefone1());
Example exampleFornecedor = Example.create(fornecedor).enableLike(MatchMode.ANYWHERE).ignoreCase();
Criteria criteria = super.getSession().createCriteria(Fornecedor.class, "fornecedor").add(exampleFornecedor);
List<Fornecedor> fornecedores = criteria.list();
for(Fornecedor f : fornecedores) {
fornecedoresMap.put(f.getId(), f);
}
return new ArrayList<Fornecedor>(fornecedoresMap.values());
}
In this case, there is no result provided by criteria.list() method. But if I remove "telefone2" and "telefone3" setters, like this...
if(fornecedor.getTelefone1() != null) fornecedor.setTelefone1("%" + fornecedor.getTelefone1() + "%");
... the criteria and the QBE returns the result correctly, but only if the telephone provided is saved in "telefone1" field.
My question is why this occurs? AFAIK, Hibernate Query By Example matches the results based on the given search fields filled, ignoring null attributes.
Thanks.
You are building a condition (with s = '%' + entered search string + '%'):
(telefone1 LIKE s) AND (telefone2 LIKE s) AND (telefone3 LIKE s)
I guess that you really want
(telefone1 LIKE s) OR (telefone2 LIKE s) OR (telefone3 LIKE s)
If that is true you can't use query by example which always produces and-connected conditions. Try to use HQL or the criteria API instead.
Related
Any help or hint would be greatly appreciated it!!
I am currently using Java 8.
I have a web service that takes an sql statement as a parameter.
That sql could have many fields in the select statement or parameters for the where clause.
In my java return statement based on the sql queries I could have many fields in the return statement.
How can I create a Java object that could have different number of fields based on the number of fields in the query select statement?
You can maybe use a HashMap for storing the query result If that is allowed
through this way, you can get the length of the total fields or do other operations that map provides.
below is the example code
public ResponseEntity<?> postData(some request) {
Map<String, Object> data = someRepository.getDataByID(someId);
// data that you get from sql query, note that you have to map it though
// in response type of sql query of whatever java tool you are using for getting the sql data
System.out.println("The fields are: " + data.keySet());
for(String fieldKey: data) {
System.out.println("key is " + key);
System.out.println("value is " + data.get(key));
}
... your logic
return new ResponseEntity(data, HttpStatus.OK);
}
I was exploring the way to return map from Hibernate.
I came to know i can do it by two ways
First one was : using map
String HQL_QUERY =
"select new map(hp.col1 , hp.col2) from HP hp where hp.col1 in (:Ids)";
test =
getSession().createQuery(HQL_QUERY).setParameterList("Ids", ids).list();
Otherone is using setResultTransformer
String HQL_QUERY =
"select hp.col1 , hp.col2 from HP hp where hp.col1 in (:Ids)";
test =
getSession().createQuery(HQL_QUERY).setParameter("Ids", ids)
.setResultTransformer(Criteria.ALIAS_TO_ENTITY_MAP).list();
In both ways i am getting same result .... no issues.
But i wanna ask if there is any advantage of using one over other.
For example if you are using map you have to write less code , but might be possible that result transformer is more efficient(not sure).
I tried to find it on google but didn't find much.
Please help
They are just two ways of expressing the same thing.
Here is a confirmation from hibernate sources : in QueryLoader.java which is the class parsing hql queries :
selectNewTransformer = HolderInstantiator.createSelectNewTransformer(
selectClause.getConstructor(),
selectClause.isMap(),
selectClause.isList());
Here the selectClause.isMap() will be true (if you want to confirm that, have a look at ConstructorNode.java)
And then in HolderInstantiator.java :
public static ResultTransformer createSelectNewTransformer(Constructor constructor, boolean returnMaps, boolean returnLists) {
if ( constructor != null ) {
return new AliasToBeanConstructorResultTransformer(constructor);
}
else if ( returnMaps ) {
return Transformers.ALIAS_TO_ENTITY_MAP;
}
else if ( returnLists ) {
return Transformers.TO_LIST;
}
else {
return null;
}
}
So i guess the map() inside the hql select clause being more readable and more concise make it the best choice. Apart from that, exactly the same thing will happen behind the scene.
I have an object with 70 attributes. For ease of use I created 2 objects, a 'main' object and a 'details' object, with 1:1 relationship based on an auto-generated integer ID. I had a SEARCH screen that allowed searching on any of the main attributes, for which I build Restriction objects for whatever the user typed in. What was nice was that I did this all through iterating through the fields and building criterion - I didn't need ugly code to specifically handle each of the 30 attributes.
Now they want to search on the details fields as well. My previous screen-field-iterating code works perfectly with no changes (the whole reason for making it 'generic'), however I cannot get the JOIN to work to query on details fields.
class House {
Integer houseID;
String address;
. . .
HouseDetails houseDetails;
}
class HouseDetails {
Integer houseID;
String color;
. . .
}
I tried to create an alias and add it to the criteria :
criteria.createAlias("houseDetails", "houseDetails");
but I get this error :
org.hibernate.QueryException: could not resolve property: color of: House
Here's the thing - I know this would work if I prefix my restrictions with the alias name, but I do NOT want to have to know which table (House or HouseDetails) the field comes from. That would ruin all the automatic looping code and create specific code for each field.
Since SQL can do this as long as the column names are unique :
select * from house, housedetails where house.houseID = housedetails.houseID
and color = 'blue';
I'm wondering how can I get this to work using criteria??
As an aside, but related to this : Is there a way to perform something like Java's introspection on Hibernate HBM.XML mapping files? A number of times I've wanted to do this to solve problems but never found an answer. For the above problem, if I could easily find out which table contained each field, I could add the prefix to the Restriction. Something like this :
// Map of search keys (columns) to searching values
for ( String key : parms.keySet() ) {
String val = parms.get(key);
if ( HIBERNATE-SAYS-KEY-IS-FROM-DETAILS-TABLE ) {
key = "houseDetails." + key;
}
criteria.add(Restrictions.eq(key,val));
}
You can make method to find table name for passed column name.
By using SessionFactory.getClassMetaData() you can get all the information about that class. Once you have ClassMetaData then you can get all the property names. An demo method is shown below:
public String findTableName(String columnName)
{
boolean found=false;
Map<String, ClassMetadata> classMetaData = sessionFactory.getAllClassMetadata();
for (Entry<String, ClassMetadata> metaData : classMetaData.entrySet())
{
String[] propertyNames = metaData.getValue().getPropertyNames();
for (String property : propertyNames)
{
if(property == columnName)
{
return metaData.getKey() + "." + property;
found=true;
break;
}
}
if(found)
break;
}
}
The alias mechanism in hibernate and the Criteria API is pretty well specified. I suggest going through the documentation a little a bit.
I think what you want is something like this:
Criteria criteria = session.createCriteria(House.class);
criteria.createAlias("houseDetails.color", "houseColor");
criteria.add(Restrictions.eq("houseColor", "red"));
I have a rather complex query (too many nested levels for either HQL or Criteria queries), so I've written it as a SQLQuery. I'd really like to use the AliasToBeanResultTransformer to transform my results into a List, but I'm having some issues. I've included code snippets below of what I've got right now.
When I log the results for the transformed query, I can see that the transformer does create a List, however, all the fields in each AdvancedClauseSearchResultDTO are null. I assume that means that I'm doing something wrong with aliasing ... that the AliasToBeanResultTransformer can't find the correct setters to call. However, the AdvancedClauseSearchResultDTO class does have public setters for each of the columns that I've aliased in my sql string. If this was a Criteria query, I'd use projections to define an alias for each column to be returned, but I'm unsure of how to accomplish the same thing using a SQLQuery.
Any advice on how to get the aliases set so that the ResultTransformer can use them? I've seen some limited documentation that suggested that using the 'as aliasName' method should work, but it doesn't seem to be for me.
Beginning snippet of query string definition, note the 'as' alias definitions
StringBuffer clauseBaseQuery = new StringBuffer();
clauseBaseQuery.append("select ");
clauseBaseQuery.append(" clauseDetail.clause_detail_id as clauseDetailId,");
clauseBaseQuery.append(" clauseDetail.clause_id as clauseId,");
clauseBaseQuery.append(" providers.provider_name as provider, ");
clauseBaseQuery.append(" products.product_name as product, ");
SQLQuery creation & setting of resultTransformer
Query query = session.createSQLQuery(clauseBaseQuery.toString());
query.setResultTransformer(new AdvancedClauseSearchResultTransformer());
return (List<AdvancedClauseSearchResultDTO>)query.list();
AdvancedClauseSearchResultTransformer class (uses AliasToBeanResultTransformer and then does some extra processing):
class AdvancedClauseSearchResultTransformer implements ResultTransformer {
//Use the aliasTransformer to do most of the work
ResultTransformer aliasTransformer = Transformers.aliasToBean(AdvancedClauseSearchResultDTO.class);
#Override
public List transformList(List list) {
log.debug("transforming CLAUSE results");
List<AdvancedClauseSearchResultDTO> result = aliasTransformer.transformList(list);
//for each row, set the status field
for (AdvancedClauseSearchResultDTO dto : result) {
log.debug("dto = " + dto);
String status = null;
Date effectiveDate = dto.getEffectiveDate();
Date terminationDate = dto.getTerminationDate();
Date now = new Date(System.currentTimeMillis());
if (now.before(effectiveDate)) {
status = "Pending";
} else if (now.after(terminationDate)) {
status = "Terminated";
} else {
status = "Active";
}
dto.setStatus(status);
if (StringUtils.isNotEmpty(dto.getReasonForAmendment())){
dto.setAmended(Boolean.TRUE);
}else{
dto.setAmended(Boolean.FALSE);
}
}
return result;
}
#Override
public Object transformTuple(Object[] os, String[] strings) {
Object result = aliasTransformer.transformTuple(os, strings);
return result;
}
}
This depends on the backend you're using, which you don't mention in your post.
Various DB backends use case insensitive naming for the columns unless you properly escape them, so they end being retrieved as CLAUSEDETAILID or clausedetailid, even when you specify the column result name with the proper case.
With PostgreSQL (and I believe Oracle, too), you have to write your query like this (note the column quoting):
StringBuffer clauseBaseQuery = new StringBuffer();
clauseBaseQuery.append("select ");
clauseBaseQuery.append(" clauseDetail.clause_detail_id as \"clauseDetailId\",");
clauseBaseQuery.append(" clauseDetail.clause_id as \"clauseId\",");
clauseBaseQuery.append(" providers.provider_name as \"provider\", ");
clauseBaseQuery.append(" products.product_name as \"product\", ");
Query query = session.createSQLQuery(clauseBaseQuery.toString());
So that will allow Hibernate to properly recognize the property and map the result to a bean, provided you also specfied the tranformation:
query.setResultTransformer(Transformers.aliasToBean(AdvancedClauseSearchResultDTO.class));
as was suggested by #zinan.yumak.
I did some more research on this today, and finally noticed a good stack trace of the underlying error I was getting, and a hibernate forum entry that helped me get past this.
The Exception I was getting is:
Caused by: org.hibernate.PropertyNotFoundException: Could not find setter for CLAUSEDETAILID
It appears as if Hibernate is taking my camel case aliases & turning them into all uppercase, so it can't find the matching setters in my AdvancedClauseSearchResultDTO class.
Here's the forum entry that pointed me in the right direction:
https://forum.hibernate.org/viewtopic.php?f=1&t=1001608
I ended up using the approach detailed in that post for my own ResultTransformer, and that's working for me.
I think it is not a good method to write a result transformer to solve
your problem. Try something like this,
Query query = session.createSQLQuery(clauseBaseQuery.toString());
query.setResultTransformer(Transformers.aliasToBean(AdvancedClauseSearchResultDTO.class));
And in AdvancedClauseSearchResultDTO class, modify setter methods to set required
fields for you. For example,
class AdvancedClauseSearchResultDTO {
private Date effectiveDate;
private String status;
.
.
public void getEffectiveDate() {
return effectiveDate;
}
public void setEffectiveDate(Date aDate) {
Date now = new Date(System.currentTimeMillis());
if (now.before(effectiveDate)) {
this.status = "Pending";
} else if (now.after(terminationDate)) {
this.status = "Terminated";
} else {
this.status = "Active";
}
this.effectiveDate = aDate;
}
}
You got the idea...
The easiest fix is to put quotation marks for the column alias like:
select first_name as "firstName" from employee
I have this method signature:
public int nrOfEntities(Class<? extends MailConfirmation> clazz, User user, String email)
I would like nrOfEntities to return the number of entities that:
Are of the concrete class clazz
Have a matching User if user != null
Have a matching email if user == null
It's the class matching I'm having a problem with. I've tried a few statements without any luck.
Can clazz have subtypes that should not be counted?
If not, is it not sufficient to create the query on clazz?
Criteria criteria = session.createCriteria(clazz);
if (user == null) {
criteria.add(Restrictions.eq("email", email);
} else {
criteria.add(Restrictions.eq("user", user);
}
int result = (Integer) criteria.setProjection(Projections.rowCount()).uniqueResult();
Now I am guessing how your mapping looks (that there are "email" and "user" properties).
If that is not working, I know that there is a pseudo property named "class", at least in HQL. Maybe you can experiment with that.
Are you looking for "from " + clazz.getSimpleName() + " where ..."?
If you want to test the class of an object, you should be able to use something like the following:
Object entity = ... // Get the entity however
boolean matchesClass = entity.getClass().equals(clazz);
If this isn't working for you, give some examples of how it fails since it should be this straightforward!