這裏是一個字符串標籤使用一個int,而不是一個解決方案身份證,但它很容易適應。
public class User {
@Id
private int id;
@Type(type = "com.example.hibernate.LabeledEnumType")
private Role role;
}
public enum Role implements LabeledEnum {
ADMIN("admin"), USER("user"), ANONYMOUS("anon");
private final String label;
Role(String label) {
this.label = label;
}
@Override
public String getLabel() {
return label;
}
}
public interface LabeledEnum {
String getLabel();
}
public final class LabeledEnumType implements DynamicParameterizedType, UserType {
private Class<? extends Enum> enumClass;
@Override
public Object assemble(Serializable cached, Object owner)
throws HibernateException {
return cached;
}
@Override
public Object deepCopy(Object value) throws HibernateException {
return value;
}
@Override
public Serializable disassemble(Object value) throws HibernateException {
return (Serializable) value;
}
@Override
public boolean equals(Object x, Object y) throws HibernateException {
return x == y;
}
@Override
public int hashCode(Object x) throws HibernateException {
return x == null ? 0 : x.hashCode();
}
@Override
public boolean isMutable() {
return false;
}
@Override
public Object nullSafeGet(ResultSet rs, String[] names, SessionImplementor session, Object owner)
throws HibernateException, SQLException {
String label = rs.getString(names[0]);
if (rs.wasNull()) {
return null;
}
for (Enum value : returnedClass().getEnumConstants()) {
if (value instanceof LabeledEnum) {
LabeledEnum labeledEnum = (LabeledEnum) value;
if (labeledEnum.getLabel().equals(label)) {
return value;
}
}
}
throw new IllegalStateException("Unknown " + returnedClass().getSimpleName() + " label");
}
@Override
public void nullSafeSet(PreparedStatement st, Object value, int index, SessionImplementor session)
throws HibernateException, SQLException {
if (value == null) {
st.setNull(index, Types.VARCHAR);
} else {
st.setString(index, ((LabeledEnum) value).getLabel());
}
}
@Override
public Object replace(Object original, Object target, Object owner)
throws HibernateException {
return original;
}
@Override
public Class<? extends Enum> returnedClass() {
return enumClass;
}
@Override
public int[] sqlTypes() {
return new int[]{Types.VARCHAR};
}
@Override
public void setParameterValues(Properties parameters) {
ParameterType params = (ParameterType) parameters.get(PARAMETER_TYPE);
enumClass = params.getReturnedClass();
}
}
使用下面的鏈接獲得一個很好的教程。這有助於我清楚地理解。 http://www.gabiaxel.com/2011/01/better-enum-mapping-with-hibernate.html – 2014-06-18 05:08:12