public class DBUtilU {
private static Session scss;
private static SessionFactory sfactory;
static {
Configuration cfg = new Configuration();
cfg.addAnnotatedClass(Userdetails.class);
cfg.addAnnotatedClass(Code.class);
cfg.addAnnotatedClass(Messages.class);
cfg.addAnnotatedClass(Comments.class);
cfg.configure();
new SchemaExport(cfg);
sfactory = cfg.buildSessionFactory();
}
}
public static List<Code> searchCodeTags(String tags) {
List<Code> codelist = new ArrayList<Code>();
try {
scss = sfactory.getCurrentSession();
scss.beginTransaction();
String query = "from Code where Tags=" + tags;
Query queryResult = scss.createQuery(query);
for(Object c : queryResult.list())
codelist.add((Code)c);
} catch (Exception e) {
e.printStackTrace();
return null;
}
return codelist;
}
package UsersProperty;
@Entity
public class Code {
@Id
@GeneratedValue
private int codeId;
private int Rating;
private String fileName;
private String OwnerName;
private String PrjName;
private String Tags;
@ManyToOne()
@JoinColumn(name="userid")
private Userdetails userdetails;
@OneToMany(targetEntity=Comments.class, mappedBy="targetCode")
private List<Comments> cm;
public int getRating() {
return Rating;
}
public void setRating(int rating) {
Rating = rating;
}
public List<Comments> getCm() {
return cm;
}
public void setCm(List<Comments> cm) {
this.cm = cm;
}
public String getFileName() {
return fileName;
}
public void setFileName(String fileName) {
this.fileName = fileName;
}
public String getOwnerName() {
return OwnerName;
}
public void setOwnerName(String ownerName) {
OwnerName = ownerName;
}
public String getPrjName() {
return PrjName;
}
public void setPrjName(String prjName) {
PrjName = prjName;
}
public String getTags() {
return Tags;
}
public void setTags(String tags) {
Tags = tags;
}
public Userdetails getUserdetails() {
return userdetails;
}
public void setUserdetails(Userdetails userdetails) {
this.userdetails = userdetails;
}
public Code(String fileName, String ownerName, String prjName,String tAgs) {
super();
this.fileName = fileName;
OwnerName = ownerName;
PrjName = prjName;
Tags=tAgs;
}
public Code() {
super();
}
public static List<Code> CodeSearch(String TAGS){
return DBUtilU.searchCodeTags(TAGS);
}
}
コンソール:
> Hibernate: select code0_.codeId as codeId1_0_, code0_.OwnerName as OwnerNam2_0_, code0_.PrjName as PrjName3_0_, code0_.Rating as Rating4_0_, code0_.Tags as Tags5_0_, code0_.fileName as fileName6_0_, code0_.userid as userid7_0_ from Code code0_ where code0_.Tags=Overloading
Jun 17, 2013 8:38:05 PM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
WARN: SQL Error: 0, SQLState: 42703
Jun 17, 2013 8:38:05 PM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
ERROR: ERROR: column "overloading" does not exist
Position: 252
org.hibernate.exception.SQLGrammarException: could not extract ResultSet
at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.Java:123)
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.Java:49)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.Java:125)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.Java:110)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.Java:61)
at org.hibernate.loader.Loader.getResultSet(Loader.Java:2036)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.Java:1836)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.Java:1815)
at org.hibernate.loader.Loader.doQuery(Loader.Java:899)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.Java:341)
at org.hibernate.loader.Loader.doList(Loader.Java:2522)
at org.hibernate.loader.Loader.doList(Loader.Java:2508)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.Java:2338)
at org.hibernate.loader.Loader.list(Loader.Java:2333)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.Java:490)
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.Java:355)
at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.Java:195)
at org.hibernate.internal.SessionImpl.list(SessionImpl.Java:1269)
at org.hibernate.internal.QueryImpl.list(QueryImpl.Java:101)
at DB.DBUtilU.searchCodeTags(DBUtilU.Java:117)
at UsersProperty.Code.CodeSearch(Code.Java:90)
at Test.Main.main(Main.Java:34)
Caused by: org.postgresql.util.PSQLException: ERROR: column "overloading" does not exist
Position: 252
at org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.Java:2157)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.Java:1886)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.Java:255)
at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.Java:555)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.Java:417)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.Java:302)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.Java:56)
... 17 more
問題:
searchCodeTags
クラスからDBUtilU
関数を実行すると発生します。ここで何が起きてるの?
次のようにクエリを変更します。
String query = "from Code where Tags='" + tags+"'";
それ以外の場合は以下のとおり:
String hql = "from Code where Tags=:tags";
Query query = session.createQuery(hql);
query.setParameter("tags",tags);
where句での比較はリテラルであり、別の列ではありません。したがって、最初のケースのように引用符で囲むか、2番目のケースのようにバインド変数を使用する必要があります。
エラーメッセージを確認してください(スタックトレースが長いことは認めますが、一般的に興味深い部分は上部にあります)。
エラー:エラー:列「オーバーロード」は存在しません
コードcode0_からここでcode0_.Tags = Overloading
引用する必要があります'Overloading'
、これは列名ではなくリテラル値だからです。さらに、バインド変数として設定します。
camelCaseを使用している場合、JPAはCamel_Caseに変換します。小文字に変換しても問題ありません。