我有一个这样的实体：
@Entity
@Table(name = "PLATFORM")
public class Platform{
@Id
@Column(name = "PLATFORM_ID")
@GeneratedValue(strategy = GenerationType.AUTO)
private Integer platformId;
@ManyToOne(fetch=FetchType.EAGER)
@JoinColumn(name="PLATFORM_TYPE_ID")
private PlatformType platformType;
//must be manytomany but how?
private List<MimeType> supportedMimeTypes;
...
我有一个MimeType类，它确实是一个org.hibernate.usertype.UserType。
import java.sql.Types;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
public class MimeType extends EnumarationType{
private static final long serialVersionUID = 1L;
public static final MimeType XML = new MimeType(new Integer(0), "XML");
public static final MimeType JSON = new MimeType(new Integer(1), "JSON");
protected static ArrayList<MimeType> list = new ArrayList<MimeType>();
static {
SQL_TYPES = new int[] { Types.INTEGER };
list.add(XML);
list.add(JSON);
}
public MimeType(){
}
public MimeType(Integer value, String label) {
super(value, label);
}
public List<?> getList() {
return list;
}
public static MimeType getById(int id) {
Iterator<MimeType> it = list.iterator();
while (it.hasNext()) {
MimeType status = it.next();
int statusId = Integer.parseInt(status.getValue());
if (statusId == id)
return status;
}
return null;
}
public static MimeType getByName(String name) {
Iterator<MimeType> it = list.iterator();
while (it.hasNext()) {
MimeType status = it.next();
String statusName = status.getLabel();
if (statusName.equalsIgnoreCase(name))
return status;
}
return null;
}
}
import java.io.Serializable;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;
import java.util.Iterator;
import java.util.List;
import org.hibernate.HibernateException;
import org.hibernate.usertype.UserType;
public abstract class EnumarationTypeBase implements UserType, Serializable {
protected static int[] SQL_TYPES = { Types.VARCHAR };
protected String label;
protected Object value;
protected String resourceKey;
public EnumarationTypeBase() {
}
public String getLabel() {
return label;
}
public void setLabel(String label) {
this.label = label;
}
public abstract List<?> getList();
private Object getValue() {
return value;
}
public void setValue(Object value) {
this.value = value;
}
public EnumarationTypeBase resolveFromValue(Object value) {
List<?> list = getList();
if (list == null)
return null;
EnumarationTypeBase result = null;
for (Iterator<?> itr = list.iterator(); itr.hasNext();) {
EnumarationTypeBase enm = (EnumarationTypeBase) itr.next();
if (enm.getValue().toString().equals(value.toString())) {
result = enm;
break;
}
}
return result;
}
public EnumarationTypeBase resolveFromLabel(Object label) {
List<?> list = getList();
if (list == null)
return null;
EnumarationTypeBase result = null;
for (Iterator<?> itr = list.iterator(); itr.hasNext();) {
EnumarationTypeBase enm = (EnumarationTypeBase) itr.next();
if (enm.getLabel().equals(label.toString())) {
result = enm;
break;
}
}
return result;
}
public String toString() {
return getLabel();
}
public int[] sqlTypes() {
return SQL_TYPES;
}
public Class<?> returnedClass() {
return getClass();
}
public Object nullSafeGet(ResultSet resultSet, String[] names, Object owner) throws HibernateException,
SQLException {
value = resultSet.getString(names[0]);
return resultSet.wasNull() ? null : resolveFromValue(value);
}
public void nullSafeSet(PreparedStatement statement, Object value, int index) throws HibernateException,
SQLException {
EnumarationTypeBase enumType = (EnumarationTypeBase) value;
if (value == null) {
statement.setNull(index, sqlTypes()[0]);
} else {
statement.setString(index, enumType.getValue().toString());
}
}
public boolean equals(Object x, Object y) {
if (x == y)
return true;
if (null == x || null == y)
return false;
return x.equals(y);
}
public boolean equals(Object obj) {
if (obj instanceof EnumarationTypeBase)
return this.getValue().equals(((EnumarationTypeBase) obj).getValue());
return super.equals(obj);
}
public Object assemble(Serializable cached, Object owner) throws HibernateException {
return cached;
}
public Serializable disassemble(Object value) throws HibernateException {
return (Serializable) value;
}
public Object replace(Object original, Object target, Object owner) throws HibernateException {
return original;
}
public Object deepCopy(Object value) {
return value;
}
public boolean isMutable() {
return false;
}
public int hashCode(Object x) throws HibernateException {
return x.hashCode();
}
public int hashCode() {
return (new Integer(this.getValue().toString())).intValue();
}
public String getResourceKey() {
if (resourceKey == null)
resourceKey = resolveFromValue(this.value).resourceKey;
return resourceKey;
}
public void setResourceKey(String resourceKey) {
this.resourceKey = resourceKey;
}
}
public abstract class EnumarationType extends EnumarationTypeBase {
protected static int[] SQL_TYPES = { Types.VARCHAR };
public EnumarationType() {
}
public EnumarationType(Integer value, String label) {
this.value = value.toString();
this.label = label;
}
public EnumarationType(String value, String label) {
this.value = value.toString();
this.label = label;
}
public EnumarationType(Integer value, String label, String resourceKey) {
this.value = value.toString();
this.label = label;
this.resourceKey = resourceKey;
}
public String getValue() {
return (String) value;
}
public BigDecimal getBigDecimalValue() {
BigDecimal tValue = new BigDecimal(getValue());
return tValue;
}
public void setValue(String value) {
this.value = value;
}
}
那么我如何定义实体平台和非实体usertype MimeType之间的多种关系。
请帮忙。
答案 0 :(得分：0)
我解决了这个问题。这是工作代码
...
@ElementCollection(targetClass = MimeType.class,fetch=FetchType.EAGER)
@CollectionTable(name = "PLATFORM_MIME_TYPE", joinColumns = @JoinColumn(name = "PLATFORM_ID"))
@Enumerated(EnumType.ORDINAL)
@Column(name = "MIME_TYPE_ID", columnDefinition="integer")
@Type(
type = Constants.ENUMERATION_TYPE,
parameters = {
@Parameter(
name = "enumClass",
value = "com.ba.reme.model.enums.MimeType"),
@Parameter(
name = "identifierMethod",
value = "toInt"),
@Parameter(
name = "valueOfMethod",
value = "fromInt")
}
)
private Set<MimeType> supportedMimeTypes;
...
和MimeType枚举：
public enum MimeType {
XML(1),
JSON(2),
RSS(3);
private int value;
MimeType(int value) {
this.value = value;
}
// the identifierMethod
public int toInt() {
return value;
}
// the valueOfMethod
public static MimeType fromInt(int value) {
switch(value) {
case 2: return JSON;
case 3: return RSS;
default: return XML;
}
}
public String toString() {
switch(this) {
case RSS: return "rss";
case JSON: return "json";
default: return "xml";
}
}
}