问题描述
美好的一天！我有两个对象:Tag和RelatedTag. Tag可以有多个RelatedTag(也是一个Tag).保存Tag及其相关标签可以正常工作.但是，当我更新Tag时，出现错误消息
Good day! I have two objects: Tag and RelatedTag. The Tag can have many RelatedTags (which is also a Tag). Saving the Tag with its related tags works fine. But when I update the Tag, it has an error saying
[PersistenceException: ERROR executing DML bindLog[] error[Unique index or primary key violation: "PRIMARY KEY ON PUBLIC.RELATED_TAG(ID)"; SQL statement:\n insert into related_tag (id, tag_id, relationship, related_notes) values (?,?,?,?) [23505-172]]]
这是Tag模型:
package models;
import java.util.*;
import javax.persistence.*;
import javax.validation.*;
import play.data.Form;
import play.data.validation.Constraints.*;
import play.db.ebean.*;
import play.db.ebean.Model.Finder;
import scala.Int;
@Entity
public class Tag extends Model{
@Id
private int id;
@Required
@MaxLength(value=100)
private String name;
@MaxLength(value=200)
private String notes;
@OneToMany(cascade=CascadeType.ALL)
public List<RelatedTag> relatedTags = new ArrayList<RelatedTag>();
public static Finder<Integer, Tag> find = new Finder(Int.class, Tag.class);
public Tag() {
}
public Tag(String name, String notes){
this.name = name;
this.notes = notes;
}
public Tag(int id, String name, String notes, List<RelatedTag> relatedTags) {
this.id = id;
this.name = name;
this.notes = notes;
this.relatedTags = relatedTags;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getNotes() {
return notes;
}
public void setNotes(String notes) {
this.notes = notes;
}
public List<RelatedTag> getRelatedTags() {
return relatedTags;
}
public void setRelatedTags(List<RelatedTag> relatedTags) {
this.relatedTags = relatedTags;
}
public static List<Tag> all() {
return find.all();
}
public static void create(Tag tag){
tag.save();
}
public static void delete(int id){
find.ref(id).delete();
}
public static void update(int id, Tag tag) {
tag.update(id); // updates this entity, by specifying the entity ID
}
public static boolean exists(Tag newTag) {
for(Tag allTags : Tag.find.all()) {
if(allTags.getName().equals(newTag.getName()))
return true;
}
return false;
}
}
这是RelatedTag模型:
package models;
import java.util.*;
import javax.persistence.*;
import javax.validation.*;
import play.data.Form;
import play.data.validation.Constraints.*;
import play.db.ebean.*;
import play.db.ebean.Model.Finder;
import scala.Int;
@Entity
public class RelatedTag extends Model {
@Id
private int id;
private String relationship;
private String relatedNotes;
public RelatedTag() {}
public RelatedTag(int id, String relationship, String relatedNotes) {
this.id = id;
this.relationship = relationship;
this.relatedNotes = relatedNotes;
}
public void setId(int id){
this.id = id;
}
public void setRelationship(String relationship){
this.relationship = relationship;
}
public void setRelatedNotes(String relatedNotes) {
this.relatedNotes = relatedNotes;
}
public int getId(){
return id;
}
public String getRelationship(){
return relationship;
}
public String getRelatedNotes() {
return relatedNotes;
}
public static boolean exists(String tagRelated) {
for(Tag tag : Tag.find.all()) {
if(tagRelated.equals(tag.getName()))
return true;
}
return false;
}
public static RelatedTag findByLabel(String tagRelated, String relation, String relatedNotes) {
RelatedTag relatedTag = null;
for(Tag tag : Tag.find.all()) {
if(tagRelated.equals(tag.getName())) {
relatedTag = new RelatedTag(tag.getId(), relation, relatedNotes);
}
}
return relatedTag;
}
public static Tag findTag(int id) {
for(Tag tag : Tag.find.all()) {
if(id == tag.getId())
return tag;
}
return null;
}
}
运行此命令(在其中更新Tag)时，会发生错误.
When I run this (in which I update a Tag), the error happens.
private static void reciprocate(Tag tag) {
List<Tag> peers = new ArrayList<Tag>();
for (RelatedTag rt : tag.getRelatedTags()) {
if(rt.getRelationship().equals("peer"))
peers.add(RelatedTag.findTag(rt.getId()));
}
for(RelatedTag rt : tag.getRelatedTags()) {
int relTemp = 0;
String relation = new String();
if (rt.getRelationship().equals("parent"))
relTemp = 1;
if (rt.getRelationship().equals("child"))
relTemp = 2;
if (rt.getRelationship().equals("peer"))
relTemp = 3;
switch(relTemp) {
case 1: relation = "child"; break;
case 2: relation = "parent"; break;
case 3: relation = "peer"; break;
}
Tag related = new Tag();
related = Tag.find.byId(RelatedTag.findTag(rt.getId()).getId());
List<RelatedTag> available = new ArrayList<RelatedTag>();
List<String> availableName = new ArrayList<String>();
for (RelatedTag rt2 : related.getRelatedTags()) {
availableName.add(RelatedTag.findTag(rt2.getId()).getName());
}
if(availableName.contains(tag.getName())) {
for(RelatedTag rt2 : related.getRelatedTags()) {
if(!RelatedTag.findTag(rt2.getId()).getName().equals(tag.getName())) {
available.add(rt2);
}
}
}
available.add(RelatedTag.findByLabel(
tag.getName(), relation,
rt.getRelatedNotes()));
related.setRelatedTags(available);
related.update(related.getId()); //HERE
}
}
请帮助我解决这个问题.迭代第一个rt后，将发生错误，但会保存其相关标签.非常感谢.
Please help me figure this out. After the first rt has been iterated, there goes the error but it saves its related tag. Thank you very much.
推荐答案
您的方法RelatedTag#findByLabel始终使用Tag类的ID创建新的RelatedTag.如果您有2个相关标签用于同一标签，则会产生2个具有相同ID的相关标签.
Your method RelatedTag#findByLabel always creates new RelatedTags with the IDs of the Tag class; if you have 2 related tags for the same tag, it will produce 2 related tags with the same ID.
查看 @GeneratedValue 和EntityManager#createQuery
这篇关于PersistenceException:更新对象时执行DML bindLog错误的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！