byte[]问题。怎么文档73中的类不好用?实施起来有错误。

出现这个错误。是byte[]没有赋值地问题。可是73文档里面的类可是处理了这种情况地呀。

    java.lang.NullPointerException

at java.io.ByteArrayInputStream.<init>(ByteArrayInputStream.java:89)

at net.sf.hibernate.lob.BlobImpl.<init>(BlobImpl.java:21)

at net.sf.hibernate.Hibernate.createBlob(Hibernate.java:301)

at com.pkpm.right.RightArchive.BinaryBlobType.nullSafeSet(BinaryBlobType.java:43)

at net.sf.hibernate.type.CustomType.nullSafeSet(CustomType.java:118)

at net.sf.hibernate.persister.EntityPersister.dehydrate(EntityPersister.java:394)

at net.sf.hibernate.persister.EntityPersister.insert(EntityPersister.java:501)

at net.sf.hibernate.persister.EntityPersister.insert(EntityPersister.java:433)

at net.sf.hibernate.impl.SessionImpl.doSave(SessionImpl.java:876)

at net.sf.hibernate.impl.SessionImpl.doSave(SessionImpl.java:817)

at net.sf.hibernate.impl.SessionImpl.saveWithGeneratedIdentifier(SessionImpl.java:737)

at net.sf.hibernate.impl.SessionImpl.save(SessionImpl.java:717)

at net.sf.hibernate.impl.SessionImpl.saveOrUpdate(SessionImpl.java:1322)

at net.sf.hibernate.engine.Cascades$4.cascade(Cascades.java:114)

at net.sf.hibernate.engine.Cascades.cascade(Cascades.java:436)

at net.sf.hibernate.engine.Cascades.cascadeCollection(Cascades.java:526)

at net.sf.hibernate.engine.Cascades.cascade(Cascades.java:452)

at net.sf.hibernate.engine.Cascades.cascade(Cascades.java:503)

at net.sf.hibernate.impl.SessionImpl.doSave(SessionImpl.java:892)

at net.sf.hibernate.impl.SessionImpl.doSave(SessionImpl.java:817)

at net.sf.hibernate.impl.SessionImpl.saveWithGeneratedIdentifier(SessionImpl.java:737)

at net.sf.hibernate.impl.SessionImpl.save(SessionImpl.java:717)

at com.pkpm.right.RightArchive.Manager.addFile(Manager.java:89)

at com.pkpm.right.RightArchive.Manager.main(Manager.java:169)

Exception in thread "main"

public class Image {
  public Image() {
  }

  public byte[] getContent() {
    return content;
  }

  public void setContent(byte[] content) {
    this.content = content;
  }

  private String name;
  public String getName(){ return name; }

  public void setName(String name) { this.name = name; }

  private int id;
  public int getId(){ return id; }

  public void setId(int id) { this.id = id; }

  public void upload(String source) {
  }

  public void upload(String source,String target) {
  }

  public int HashCode(){
    return id;
  }

  private byte[] content;
}

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping SYSTEM "http://hibernate.sourceforge.net/hibernate-mapping-2.0.dtd">
<hibernate-mapping>
<class name="Image" table="image">
<id name="id" column="id" type="int" unsaved-value="0">
<generator class="identity"/>
</id>
<property name="name" column="name" type="java.lang.String" length="20" not-null="false"/>
<property name="content" column="content" type="BinaryBlobType" not-null="false"/>
</class>
</hibernate-mapping>


请斑竹加以指点。项目急用。

出问题的代码要贴出来啊。

btw，
public int HashCode(){
return id;
}

是复写hashCode()嘛？。。。。。。

Session session=sessions.openSession();
    Transaction t =   null;
    Image image=new Image();
    image.setName("pp");
    try{
      t=session.beginTransaction();
      session.save(image);
      session.flush();
      t.commit();
    }catch(HibernateException e){
      if(t != null) t.rollback();
      throw e;
    }finally{
      session.close();
    }

出错感觉就是没有设置byte[]属性。

我用的数据库是sqlserver，是不是这个问题？有点搞不懂了。
也不是为空的问题，我把byte[] 已经填上内容了。

  Hit uncaught exception java.lang.ClassCastException
   java.lang.ClassCastException

经过查验，感觉是73文档提供地类有问题，放弃使用byte[] 换用Blob。通过调试。