我只是解决了像你这样的问题。关于这件事的信息很少。正如@ms03 所说...更好的方法是创建一个新类型和一个实现此类型的类并处理用于设置/获取数据库的 java 对象。
首先在您的实体上，您必须为您的参数声明类型。
@Entity
@Table(name="user_app")
@TypeDefs(value={@TypeDef(name="convertInet",typeClass=PgInetType.class),
@TypeDef(name="convertMacaddr",typeClass=PgMacaddrType.class)})
public class User implements Serializable {
//some parameters
@Type(type="convertMacaddr")
private PgMacaddr mac;
@Type(type="convertInet")
private PgInet ip;
//getters and setters, equals, hashcode, toString
}
第二次创建为java处理的新对象，它必须有一个默认构造，一个用于处理来自DB的数据的构造并且是可序列化的。
public class PgInet implements Serializable {
private static final long serialVersionUID = 1L;
private String address;
public PgInet(String address){
this.address=address;
}
public PgInet(){
this.address=null;
}
//Getters,setters,hashcode, equal and toString
}
最后一步你必须创建一个自定义类型
public class PgInetType implements UserType{
@Override
public int[] sqlTypes() {
//Because inet,macaddr,cdir...and unkwon type for java, yo must
// define Types.OTHER
return new int[] { Types.OTHER };
}
@Override
public Class returnedClass() {
//Object created to be handled for java
return PgInet.class;
}
@Override
public boolean equals(Object x, Object y) throws HibernateException {
return ObjectUtils.nullSafeEquals(x, y);
}
@Override
public int hashCode(Object x) throws HibernateException {
if(x!=null)
return x.hashCode();
else
return 0;
}
@Override
public Object nullSafeGet(ResultSet rs, String[] names,
SessionImplementor session, Object owner)
throws HibernateException, SQLException {
//Translation from DB to Java
PgInet address=null;
String ip=rs.getString(names[0]);
if(ip!=null){
address=new PgInet(ip);
}
return address;
}
@Override
public void nullSafeSet(PreparedStatement st, Object value, int index,
SessionImplementor session) throws HibernateException, SQLException {
//Translation from java to DB
if(value==null){
st.setNull(index, Types.VARCHAR);
}else{
//As inet,macaddr,cdir...are new types object on Postgresql you must
//create the specific postgresql object and to insert it
//I created 2 new cast on postgresql: inet As varchar, varchar AS inet
//but I think it's not neccesary because macaddr type works fine without
//postgresl casting
st.setObject(index, getInet(value, st.getConnection()));
}
}
private Object getInet(Object value, Connection connection) {
//Expected object on postgresql
Object tempInet = null;
ClassLoader connectionClassLoader = connection.getClass().getClassLoader();
try {
//Class which will create the postgresql
Class aPGObjectClass =connectionClassLoader.loadClass("org.postgresql.util.PGobject");
Constructor ct = aPGObjectClass.getConstructor(null);
try {
tempInet = ct.newInstance(null);
} catch (InstantiationException | IllegalAccessException
| IllegalArgumentException | InvocationTargetException e2) {
// TODO Auto-generated catch block
e2.printStackTrace();
}
Method setTypeMethod = aPGObjectClass.getMethod("setType", new Class[]{String.class});
try {
//Setting postgresql type, inet in this case
setTypeMethod.invoke(tempInet, new Object[]{"inet"});
} catch (IllegalAccessException | IllegalArgumentException
| InvocationTargetException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
Method setValueMethod = aPGObjectClass.getMethod("setValue", new Class[]{String.class});
try {
setValueMethod.invoke(tempInet, new Object[]{value.toString()});
} catch (IllegalAccessException | IllegalArgumentException
| InvocationTargetException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (ClassNotFoundException e) {
} catch (NoSuchMethodException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (SecurityException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return tempInet;
}
@Override
public Object deepCopy(Object value) throws HibernateException {
if(value==null)
return null;
else{
PgInet PgInetNew=new PgInet();
PgInet PgInetOriginal=(PgInet)value;
PgInetNew.setAddress(PgInetOriginal.getAddress());
return PgInetNew;
}
}
@Override
public boolean isMutable() {
return false;
}
@Override
public Serializable disassemble(Object value) throws HibernateException {
Object deepCopy=deepCopy(value);
if(!(deepCopy instanceof Serializable))
return (Serializable)deepCopy;
return null;
}
@Override
public Object assemble(Serializable cached, Object owner)
throws HibernateException {
return deepCopy(cached);
}
@Override
public Object replace(Object original, Object target, Object owner)
throws HibernateException {
return deepCopy(original);
}
}
当我从 DB 插入或获取一行时，这种方式对我来说很好。