I am trying to implement and use the composite pattern in my system.
The problem is that I cant retrieve all the hierarchy of entities from the backend.
I am not sure what is the problem, the fetch is fine. So, I am not sure if is hibernate.
Lets see, these are my entities.
#Entity
#Table(name = "game")
#Cache(usage = CacheConcurrencyStrategy.NONSTRICT_READ_WRITE)
#Document(indexName = "game")
public class Game extends AbstractAuditingEntity implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#NotNull
#Column(name = "name", nullable = false)
private String name;
#Column(name = "detail")
private String detail;
#OneToOne(fetch = FetchType.EAGER, cascade = CascadeType.ALL)
#JoinColumn(name = "rule_id")
private GameRule gameRule;
...
In this class I save the main "GameRule"
#Entity
#Table(name = "game_rule")
#Inheritance(strategy = InheritanceType.SINGLE_TABLE)
#DiscriminatorColumn(name = "type", discriminatorType = DiscriminatorType.STRING)
#DiscriminatorValue("rule")
#JsonTypeInfo(
use = JsonTypeInfo.Id.NAME,
include = JsonTypeInfo.As.PROPERTY,
property = "_class")
#JsonSubTypes({
#JsonSubTypes.Type(value = SimpleRule.class, name = "SimpleRule"),
#JsonSubTypes.Type(value = CompositeRule.class, name = "CompositeRule") })
public abstract class GameRule implements Serializable {
private static final long serialVersionUID = -4597791997254248990L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "id", nullable = false)
private Long id;
private String operator;
In this class I save a list of GameRules
#Entity
#Inheritance(strategy = InheritanceType.SINGLE_TABLE)
#DiscriminatorColumn(discriminatorType = DiscriminatorType.STRING)
#DiscriminatorValue("group")
public class CompositeRule extends GameRule {
private static final long serialVersionUID = 6197786758476721324L;
#ManyToMany(fetch = FetchType.EAGER, cascade = { CascadeType.ALL })
#JoinTable(name = "game_rules_hierarchy",
joinColumns = #JoinColumn(name = "parent_rule_id", referencedColumnName = "id"),
inverseJoinColumns = #JoinColumn(name = "child_rule_id", referencedColumnName = "id"))
#OrderBy("id")
private List<GameRule> rules;
public List<GameRule> getRules() { return rules; }
public void setRules(List<GameRule> rules) { this.rules = rules; }
And now the leaf entity.
#Entity
#Inheritance(strategy = InheritanceType.SINGLE_TABLE)
#DiscriminatorColumn(discriminatorType = DiscriminatorType.STRING)
#DiscriminatorValue("simple")
public class SimpleRule extends GameRule {
private static final long serialVersionUID = 6197786758476721324L;
private String variable;
private Double value;
#ManyToOne
#NotNull
private Device device;
Now, the restController to retrieve the data
#RequestMapping(value = "/games/{id}",
method = RequestMethod.GET,
produces = MediaType.APPLICATION_JSON_VALUE)
#Timed
#Transactional
public ResponseEntity<Game> getGame(#PathVariable Long id) {
log.debug("REST request to get Game : {}", id);
Game game = gameRepository.findOne(id);
return Optional.ofNullable(game)
.map(result -> new ResponseEntity<>(
result,
HttpStatus.OK))
.orElse(new ResponseEntity<>(HttpStatus.NOT_FOUND));
}
Now in the view I am able to receive the CompositeRule objects but nothing about the simpleRule objects.
From the UI (angular), I am using this JSON to load the hierarchy.
vm.game.gameRule = {id: null, operator: "", type:null, _class:"CompositeRule",
rules: [ {id: null, operator: "", type:null, _class:"CompositeRule", rules:
[{id: null, type:null, _class:"SimpleRule", device: "6", variable: "POWER", operator: ">", value: "100"},
{id: null, type:null, _class:"SimpleRule", device: "6", variable: "POWER", operator: ">", value: "100"}]}
]};
This is loaded succesfully in the DB. But the problem is when I try to retrieve the entire hierarchy. Currently I am receiving only the CompositeRule objects, somthing like:
vm.game.gameRule = {id: 1, operator: "", type:null, _class:"CompositeRule",
rules: [ {id: 2, operator: "", type:null, _class:"CompositeRule", rules:[]} ]};]
In the RestController I am able to see all the hierarchy objects. I am not sure what the problem is.
Thanks for reading.
MY BAD!
Everything was fine. My problem is in the console logs. It seems that the console in chrome is not showing all the hierarchy. But if I go to the network view I am able to see everything.
Thanks.
Related
I want to have one-to-one uni-directional mapping with 2 child entities using shared primary key. Below are model classes
public class Template implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "templatekey")
Integer templateKey;
#Column(name = "templateid", unique = true)
String templateId;
#OneToOne(cascade = CascadeType.ALL, optional = false)
#PrimaryKeyJoinColumn(name = "templatekey", referencedColumnName = "templatekey")
InstantOfferNoEsp instantOfferNoEsp;
#OneToOne(cascade = CascadeType.ALL, optional = false)
#PrimaryKeyJoinColumn(name = "templatekey", referencedColumnName = "templatekey")
Mobile mobile;
//constructor , setter and getters
}
Child 1 :
public class Mobile implements Serializable {
private static final long serialVersionUID = 1L;
#Id
#Column(name = "templatekey")
Integer templateKey;
String mobileNewUrl;
//constructor , setter and getters
}
Child 2:
public class InstantOfferNoEsp {
#Id
#Column(name = "templatekey")
Integer templateKey;
String offerCodeType;
String headerUrl;
//constructor , setter and getters
}
I want templateKey as PK in all tables. and I am calling templateRepository.save(template); to save all entities at once but its not working and getting ids for this class must be manually assigned before calling save() error.
Any suggestions would be of great help. Thank you.
I was able to do what you want with bidirectional #OneToOne like below:
#Entity
public class Mobile {
#Id
Integer templateKey;
#OneToOne
#MapsId
#JoinColumn(name = "templatekey")
Template template;
// ...
}
#Entity
public class InstantOfferNoEsp {
#Id
Integer templateKey;
#OneToOne
#MapsId
#JoinColumn(name = "templatekey")
Template template;
// ...
}
#Entity
public class Template {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "templatekey")
Integer templateKey;
#OneToOne(cascade = CascadeType.ALL, mappedBy = "template", optional = false)
InstantOfferNoEsp instantOfferNoEsp;
#OneToOne(cascade = CascadeType.ALL, mappedBy = "template", optional = false)
Mobile mobile;
// ...
public void setMobile(Mobile mobile)
{
this.mobile = mobile;
this.mobile.setTemplate(this);
}
public void setInstantOfferNoEsp(InstantOfferNoEsp instantOfferNoEsp)
{
this.instantOfferNoEsp = instantOfferNoEsp;
this.instantOfferNoEsp.setTemplate(this);
}
}
and an example of saving:
Mobile mobile = new Mobile();
mobile.setMobileNewUrl("MOB1");
InstantOfferNoEsp instant = new InstantOfferNoEsp();
instant.setOfferCodeType("INST_OFF1");
Template template = new Template();
template.setTemplateId("TMP1");
template.setInstantOffer(instant);
template.setMobile(mobile);
entityManager.persist(template);
P.S. The following mapping works too, but only if we set Template.templateKey manually.
#Entity
public class Template
{
#Id
// #GeneratedValue(strategy = GenerationType.AUTO)
#Column(name = "templatekey")
Integer templateKey;
#OneToOne(cascade = CascadeType.ALL, optional = false)
#JoinColumn(name = "templatekey", insertable = false, updatable = false)
InstantOfferNoEsp instantOfferNoEsp;
#OneToOne(cascade = CascadeType.ALL, optional = false)
#JoinColumn(name = "templatekey", insertable = false, updatable = false)
Mobile mobile;
// ...
}
and an example of saving:
Mobile mobile = new Mobile();
mobile.setMobileNewUrl("MOB1");
InstantOfferNoEsp instant = new InstantOfferNoEsp();
instant.setOfferCodeType("INST_OFF1");
Template template = new Template();
template.setTemplateKey(20);
template.setTemplateId("TMP1");
template.setInstantOffer(instant);
template.setMobile(mobile);
entityManager.persist(template);
Also I would suggest your explicitly specify what generation strategy you want to use (do not use GenerationType.AUTO) and use corresponding object wrapper classes instead of primitive types for #Id fields.
I have such entities:
Bonus_Request entity:
#Entity
#Table(name = "bonus_request")
public class BonusRequest {
//some code above...
#OneToMany(fetch = FetchType.EAGER, mappedBy = "bonusRequest")
#JsonManagedReference(value = "parameter-bonus_request")
private Set<BonusRequestParameter> parameters;
}
Bonus_Request_Parameter entity:
#Entity
#Table(name = "bonus_request_parameter")
public class BonusRequestParameter {
#Id
#GeneratedValue(strategy = GenerationType.AUTO)
private Long id;
#Size(max = 30)
#Column(name = "parameter", nullable = false)
private String parameter;
#Size(max = 50)
#Column(name = "value", nullable = false)
private String value;
#JoinColumn(name = "bonus_request_id", nullable = false)
#ManyToOne(fetch = FetchType.LAZY)
#JsonBackReference(value = "parameter-bonus_request")
private BonusRequest bonusRequest;
}
I wonder if it is possible to map the BonusRequestParameter entity as a java.util.Map field in the BonusRequest entity.
For example:
#Entity
#Table(name = "bonus_request")
public class BonusRequest {
#OneToMany(fetch = FetchType.EAGER, mappedBy = "bonusRequest")
private Map<String, String> parameters; //String parameter, String value
}
I use:
Spring Data JPA - 2.1.7
PostgreSQL DB - 10.7
This will work. It loads the map eagerly by default.
#Entity
#Table(name = "bonus_request")
public class BonusRequest {
...
#ElementCollection
private Map<String, String> parameters; //String parameter, String value
}
Resolved with this:
#ElementCollection(fetch = FetchType.EAGER)
#CollectionTable(name = "bonus_request_parameter",
joinColumns = {#JoinColumn(name = "bonus_request_id", referencedColumnName = "id")})
#MapKeyColumn(name = "parameter")
#Column(name = "value")
private Map<String, String> parameters;
Thank you for help.
I have a class called Tag:
#Entity
#Table(name = "tags")
public class Tag {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String name;
#ManyToMany(fetch = FetchType.LAZY,
cascade = {
CascadeType.PERSIST,
CascadeType.MERGE
},
mappedBy = "tags")
private Set<Post> posts = new HashSet<>();
...
}
And a class called Post
#Entity
#Table(name = "posts")
public class Post {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
#ManyToMany(fetch = FetchType.LAZY,
cascade = {
CascadeType.PERSIST,
CascadeType.MERGE
})
#JoinTable(name = "post_tags",
joinColumns = { #JoinColumn(name = "post_id") },
inverseJoinColumns = { #JoinColumn(name = "tag_id") })
private Set<Tag> tags = new HashSet<>();
...
}
It creates another table named post_tags.
How can I write a Controller to access that table as it is not similar a repository?
Is there more easy and convenient way to implement ManyToMany relationship ?
My pom.xml
You don't need to access that relation table manually. You can load load all Tag entities, and then load all the referenced Post entities.
The relation table is enterily managed by your ORM frameork.
But, if you still want to access the relation table, you can use native queries in your Spring Data JPA repository, e.g.
#Query(value="select post_id, tag_id from post_tags", nativeQuery=true)
List<PostTag> loadPostTags();
PostTag class is not a jpa-managed entity and must match the structue of the returned table:
public class PostTag {
private long postId;
private long tagId;
// getter, setter
}
Use this way
#Entity
#Table(name = "tags")
public class Tag {
#Id
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long id;
private String name;
#ManyToMany(cascade = CascadeType.ALL)
#JoinTable(name = "post_tags",
joinColumns = { #JoinColumn(name = "id") },
inverseJoinColumns = { #JoinColumn(name = "post_id") })
private Set<Post> posts = new HashSet<>();
...
}
#Entity
#Table(name = "posts")
public class Post {
#Id
#Column(name = "post_id")
#GeneratedValue(strategy = GenerationType.IDENTITY)
private Long postId;
...
}
I mapped two entities to those following classes :
#Getter
#Entity
#Table(name = "users")
#JsonIdentityInfo(generator = PropertyGenerator.class,
property = "id")
#SequenceGenerator(name = "id-generator", sequenceName = "seq_users")
#EqualsAndHashCode(onlyExplicitlyIncluded = true, callSuper = false)
#NoArgsConstructor(access = PROTECTED)
#RequiredArgsConstructor
public class User extends IdentifiedById {
#Include
#NonNull
#Column(name = "email_address", unique = true)
private String emailAddress;
#Setter
#JsonIgnore
private String hash;
#Setter
private boolean admin;
#OneToMany(
mappedBy = "user",
orphanRemoval = true,
cascade = ALL
)
#JsonIgnoreProperties("user")
private Set<Cart> carts;
{
carts = new HashSet<>(0);
}
}
#Getter
#Entity
#Table(
name = "carts",
uniqueConstraints = #UniqueConstraint(
columnNames = {
"creation_time",
"user_id"
}
)
)
#JsonIdentityInfo(generator = PropertyGenerator.class,
property = "id")
#SequenceGenerator(
name = "id-generator",
sequenceName = "seq_carts"
)
#EqualsAndHashCode(
callSuper = false
)
#RequiredArgsConstructor
#NoArgsConstructor(access = PROTECTED)
public class Cart extends IdentifiedById {
#NonNull
#Column(name = "creation_time")
private LocalDateTime creationTime;
#NonNull
#ManyToOne(cascade = ALL)
#JoinColumn(
name = "user_id",
referencedColumnName = "id"
)
#JsonManagedReference
private User user;
#Exclude
#JsonProperty("productStoreQuantities")
#JsonSerialize(converter = AdditionConverter.class)
#OneToMany(mappedBy = "cart", orphanRemoval = true, cascade = ALL)
private Set<Addition> additions;
{
additions = new HashSet<>(0);
}
}
If I retrieve a user, its carts do not contain its reference, it is fine by me.
Now from a rest endpoint perspective I would like not to serialize users along with their carts if one requests multiple users like so :
**/api/users -> {"id":1, "emailAddress":"test#test.test", "admin": false}**
**/api/users/1 -> {"id":1, "emailAddress":"test#test.test", "admin": false, "carts": [...]}**
Thus, I created a wrapper class named Users containing a list of users annotated with #JsonValue and #JsonIgnoreProperties("carts") :
#RequiredArgsConstructor
public class Users implements Serializable, List<User> {
#Delegate
#JsonValue
#JsonIgnoreProperties("carts")
private final List<User> values;
}
I don't know why but carts keep being serialized, I heard that #JsonIgnoreProperties does not work on collections and arrays but it does in my first case.
You should use JsonIgnoreProperties in a class level.
This is well explained in this post
https://www.baeldung.com/jackson-ignore-properties-on-serialization
I m new to Spring Boot. I have a table (Team) that has resources, am storing in a separate table (Resources) and have team_resource mapping table (with fields teamid, resourceid). My question is should I have a domain class for the mapping_table too ?
When I m inserting a new team (POST) with resources I create entry in all 3 tables. I m using facade/dao pattern for writing/ reading to the DB. I have to handle when the team is modified/ deleted. Should I have a domain class for the mapping_table?
There are multiple approaches you can handle it
Approach 1
Define #ManyToMany between your Team and Resources entity like this:
In Team Entity
#ManyToMany(fetch = FetchType.LAZY,
cascade = {
CascadeType.PERSIST,
CascadeType.MERGE
})
#JoinTable(name = "resources",
joinColumns = { #JoinColumn(name = "id") },
inverseJoinColumns = { #JoinColumn(name = "id") })
private Set<Resources> resources= new HashSet<>();
In your resources entity:
#ManyToMany(fetch = FetchType.LAZY,
cascade = {
CascadeType.PERSIST,
CascadeType.MERGE
},
mappedBy = "resources")
private Set<Team> teams= new HashSet<>();
Approach 2
#Entity
#Table(name = "team_resources")
public class TeamResources implements Serializable {
#EmbeddedId
private TeamResourcesId id;
#ManyToOne
#JoinColumn(name = "team_id", referencedColumnName = "id", insertable = false, updatable = false)
private Team team;
#ManyToOne
#JoinColumn(name = "resources_id", referencedColumnName = "id", insertable = false, updatable = false)
private Resources resources;
public TeamResources (Team u, Resources r) {
// create primary key
this.id = new TeamResourcesId (u.getUserId(), q.getQuestionId());
// initialize attributes
this.user = u;
this.question = q;
}
#Embeddable
public static class TeamResourcesId implements Serializable {
#Column(name = "team_id")
protected Long teamId;
#Column(name = "resources_id")
protected Long resourcesId;
public TeamResourcesId () {
}
public TeamResourcesId (Long teamId, Long resourcesId) {
this.teamId= teamId;
this.resourcesId= resourcesId;
}
//Getter , setter. equal and hash
}
so to answer your question, follow second approach and its good to not define bidirectional approach as it can lead to some run time problem if not handled properly.