私はこの検索から多くのトピックを読んできたので、3日間正直に試してみました. この時点で、TaskListTopComponent (ウィンドウ) と、Todo.java というエンティティ クラスがあります。Todo エンティティ クラスには、DBF のメモ フィールドである列 TDDETAILS があります。次のコードを使用してデータを取得しようとしています。
@Column(name = "TDDETAILS")
@Lob
private String details;
public String getDetails() {
return details;
}
public void setDetails(String details) {
this.details = details;
}
上記のコードを削除すると、アプリケーションは完全に機能し、他の 10 以上の列はすべて取得、変更、追加、および削除できます。
ただし、TDDETAILS フィールドが必要で、上記のコードを使用すると次のエラーが発生します。
Internal Exception: java.sql.SQLException: [Microsoft][ODBC Visual FoxPro Driver]Feature is not available.
Error Code: 0
Call: SELECT TDTDKEY, TDBILLABLE, TDEMAILED, TDFLATRATE, TDADD_DATE, TDADD_TERM, TDADD_TIME, TDADD_USER, TDCHG_DATE, TDCHG_NUMB, TDCHG_TERM, TDCHG_TIME, TDCHG_USER, TDDETAILS, TDDATEDONE, TDFOLLOWUP, TDINTERNAL, TDPRIVATE, TDREQUIRED, TDSRED, TDTAKEN, TDDESCRIP, TDPRIORITY, TDCMKEY, TDCNKEY, TDJTKEY, TDPYKEY, TDURKEYAS, TDURKEYTB FROM TODO
Query: ReadAllQuery(name="Todo.findAll" referenceClass=Todo sql="SELECT TDTDKEY, TDBILLABLE, TDEMAILED, TDFLATRATE, TDADD_DATE, TDADD_TERM, TDADD_TIME, TDADD_USER, TDCHG_DATE, TDCHG_NUMB, TDCHG_TERM, TDCHG_TIME, TDCHG_USER, TDDETAILS, TDDATEDONE, TDFOLLOWUP, TDINTERNAL, TDPRIVATE, TDREQUIRED, TDSRED, TDTAKEN, TDDESCRIP, TDPRIORITY, TDCMKEY, TDCNKEY, TDJTKEY, TDPYKEY, TDURKEYAS, TDURKEYTB FROM TODO")
INFO [org.netbeans.core.windows.persistence]: [PersistenceManager.getTopComponentForID] Problem when deserializing TopComponent for tcID:'TaskListTopComponent'. Reason: Cannot create instance of com.waudware.viewer.TaskListTopComponent
私のpersistence.xmlは次のようになります。
<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" xmlns="http://java.sun.com/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd">
<persistence-unit name="MogEntityLivedataPU" transaction-type="RESOURCE_LOCAL">
<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>
<class>entity.Todo</class>
<properties>
<property name="javax.persistence.jdbc.url" value="jdbc:odbc:MogDev_livedata_ODBC"/>
<property name="javax.persistence.jdbc.password" value=""/>
<property name="javax.persistence.jdbc.driver" value="sun.jdbc.odbc.JdbcOdbcDriver"/>
<property name="javax.persistence.jdbc.user" value=""/>
<property name="javax.persistence.jdbc.user" value=""/>
</properties>
</persistence-unit>
</persistence>
これをどのように修正できるかについて、どんな助けでも大歓迎です。ありがとう!
編集:
さて、文字通り2つのファイルで構成される新しいプロジェクトを作成しようとしました-エンティティ(私はjarに作成します)とメインクラス:
todo.java
package entity;
import java.io.Serializable;
import javax.persistence.*;
import javax.xml.bind.annotation.XmlRootElement;
@Entity
@Table(name = "TODO")
@XmlRootElement
@NamedQueries({
@NamedQuery(name = "Todo.findAll", query = "SELECT c FROM Todo c")})
public class Todo implements Serializable {
private static final long serialVersionUID = 1L;
@Id
@Column(name = "TDTDKEY")
private String id;
@Lob
@Column(name = "TDDETAILS")
private byte[] details;
public byte[] getDetails() {
return details;
}
public void setDetails(byte[] details) {
this.details = details;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
@Override
public int hashCode() {
int hash = 0;
hash += (id != null ? id.hashCode() : 0);
return hash;
}
@Override
public boolean equals(Object object) {
// TODO: Warning - this method won't work in the case the id fields are not set
if (!(object instanceof Todo)) {
return false;
}
Todo other = (Todo) object;
if ((this.id == null && other.id != null) || (this.id != null && !this.id.equals(other.id))) {
return false;
}
return true;
}
@Override
public String toString() {
return "entity.Todo[ id=" + id + " ]";
}
}
RetrieveMemo.java
package retrievememo;
import entity.Todo;
import java.util.List;
import javax.persistence.Query;
import javax.persistence.EntityManager;
import javax.persistence.Persistence;
public class RetrieveMemo {
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
EntityManager entityManager = Persistence.createEntityManagerFactory("MemoEntityPU").createEntityManager();
Query query = entityManager.createNamedQuery("Todo.findAll");
List<Todo> resultList = query.getResultList();
System.out.println("Memo1:>" + resultList.get(1).getDetails() + "<");
}
}
完全なスタック トレースは次のとおりです。
[EL Info]: 2012-07-16 09:10:14.382--ServerSession(20248218)--EclipseLink, version: Eclipse Persistence Services - 2.3.0.v20110604-r9504
[EL Info]: 2012-07-16 09:10:14.491--Not able to detect platform for vendor name [Visual FoxPro]. Defaulting to [org.eclipse.persistence.platform.database.DatabasePlatform]. The database dialect used may not match with the database you are using. Please explicitly provide a platform using property eclipselink.platform.class.name.
[EL Info]: 2012-07-16 09:10:15.851--ServerSession(20248218)--file:/Y:/NetBeansProjects/MemoEntity/build/classes/_MemoEntityPU login successful
[EL Warning]: 2012-07-16 09:10:16.899--UnitOfWork(6597453)--Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.0.v20110604-r9504): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: [Microsoft][ODBC Visual FoxPro Driver]Feature is not available.
Error Code: 0
Call: SELECT TDTDKEY, TDDETAILS FROM TODO
Query: ReadAllQuery(name="Todo.findAll" referenceClass=Todo sql="SELECT TDTDKEY, TDDETAILS FROM TODO")
Exception in thread "main" Local Exception Stack:
Exception [EclipseLink-4002] (Eclipse Persistence Services - 2.3.0.v20110604-r9504): org.eclipse.persistence.exceptions.DatabaseException
Internal Exception: java.sql.SQLException: [Microsoft][ODBC Visual FoxPro Driver]Feature is not available.
Error Code: 0
Call: SELECT TDTDKEY, TDDETAILS FROM TODO
Query: ReadAllQuery(name="Todo.findAll" referenceClass=Todo sql="SELECT TDTDKEY, TDDETAILS FROM TODO")
at org.eclipse.persistence.exceptions.DatabaseException.sqlException(DatabaseException.java:324)
at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.getObject(DatabaseAccessor.java:1237)
at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.fetchRow(DatabaseAccessor.java:999)
at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.processResultSet(DatabaseAccessor.java:723)
at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.basicExecuteCall(DatabaseAccessor.java:621)
at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.executeCall(DatabaseAccessor.java:535)
at org.eclipse.persistence.internal.sessions.AbstractSession.basicExecuteCall(AbstractSession.java:1702)
at org.eclipse.persistence.sessions.server.ServerSession.executeCall(ServerSession.java:566)
at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:207)
at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeCall(DatasourceCallQueryMechanism.java:193)
at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.executeSelectCall(DatasourceCallQueryMechanism.java:264)
at org.eclipse.persistence.internal.queries.DatasourceCallQueryMechanism.selectAllRows(DatasourceCallQueryMechanism.java:646)
at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRowsFromTable(ExpressionQueryMechanism.java:2592)
at org.eclipse.persistence.internal.queries.ExpressionQueryMechanism.selectAllRows(ExpressionQueryMechanism.java:2551)
at org.eclipse.persistence.queries.ReadAllQuery.executeObjectLevelReadQuery(ReadAllQuery.java:418)
at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeDatabaseQuery(ObjectLevelReadQuery.java:1097)
at org.eclipse.persistence.queries.DatabaseQuery.execute(DatabaseQuery.java:829)
at org.eclipse.persistence.queries.ObjectLevelReadQuery.execute(ObjectLevelReadQuery.java:1056)
at org.eclipse.persistence.queries.ReadAllQuery.execute(ReadAllQuery.java:390)
at org.eclipse.persistence.queries.ObjectLevelReadQuery.executeInUnitOfWork(ObjectLevelReadQuery.java:1144)
at org.eclipse.persistence.internal.sessions.UnitOfWorkImpl.internalExecuteQuery(UnitOfWorkImpl.java:2863)
at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1501)
at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1483)
at org.eclipse.persistence.internal.sessions.AbstractSession.executeQuery(AbstractSession.java:1457)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.executeReadQuery(EJBQueryImpl.java:485)
at org.eclipse.persistence.internal.jpa.EJBQueryImpl.getResultList(EJBQueryImpl.java:742)
at retrievememo.RetrieveMemo.main(RetrieveMemo.java:26)
Caused by: java.sql.SQLException: [Microsoft][ODBC Visual FoxPro Driver]Feature is not available.
at sun.jdbc.odbc.JdbcOdbcResultSet.getString(JdbcOdbcResultSet.java:318)
at sun.jdbc.odbc.JdbcOdbcResultSet.getObject(JdbcOdbcResultSet.java:1678)
at org.eclipse.persistence.internal.databaseaccess.DatabasePlatform.getObjectFromResultSet(DatabasePlatform.java:1216)
at org.eclipse.persistence.internal.databaseaccess.DatabaseAccessor.getObject(DatabaseAccessor.java:1206)
... 25 more
Java Result: 1
BUILD SUCCESSFUL (total time: 11 seconds)
Edit2:実際にエンティティを使用しなければ、問題なく動作するようです。私の質問は、エンティティで機能させるにはどうすればよいですか? 問題はEclipseLinkにあるはずですか?
以下のアプローチが機能します。
package retrievememo;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.Statement;
import java.util.logging.Level;
import java.util.logging.Logger;
public class RetrieveMemo {
public static void main(String[] args) {
try {
// EntityManager entityManager = Persistence.createEntityManagerFactory("MemoEntityPU").createEntityManager();
// Query query = entityManager.createNamedQuery("Todo.findAll");
// List<Todo> resultList = query.getResultList();
// System.out.println("Memo1:>" + resultList.get(1).getDetails() + "<");
Connection conn = getConnection();
Statement st = conn.createStatement();
ResultSet rs = st.executeQuery("SELECT TDDETAILS FROM todo");
while (rs.next())
{
System.out.println(rs.getString("TDDETAILS"));
}
st.close();
conn.close();
} catch (Exception ex) {
Logger.getLogger(RetrieveMemo.class.getName()).log(Level.SEVERE, null, ex);
}
}
private static Connection getConnection() throws Exception {
String driver = "sun.jdbc.odbc.JdbcOdbcDriver";
String url = "jdbc:odbc:MogDev_livedata_ODBC";
String username = "";
String password = "";
Class.forName(driver);
return DriverManager.getConnection(url, username, password);
}
}