如何用創建和更新的日期有一個枚舉查找表？

Question

我正在使用Spring + Hibernate來處理數據訪問層操作。我想在數據庫中創建一個枚舉查找表如下屬性：

1. 代碼
2. 說明
3. 創建日期
4. 更新日期

我的代碼照顧枚舉查找表。我不知道如何在創建日期和更新日期中添加其他枚舉類可以使用的方式。

有什麼建議嗎？

Answer 1

Enum現在對我來說比以往更有意義。添加所有數據字段並創建一個構造函數。 保存所需的自定義枚舉。它在這裏提到：旨在考察StringValuedEnums

public enum Samples implements StringValuedEnum { 
SampleA("V", "Sample A"), 
SampleB("M", "Sample B"); 

private String dbCode; 
private String description; 

Brand(String dbCode, String description){ 
    this.setDbCode(dbCode); 
    this.setDescription(description); 
} 


@Override 
public String getDbCode() { 
    return this.dbCode; 
} 

public void setDbCode(String dbCode) { 
    this.dbCode = dbCode; 
} 

public String getDescription() { 
    return description; 
} 

public void setDescription(String description) { 
    this.description = description; 
} 
} 

/** * 的實用工具類。 */

public class StringValuedEnumReflect { 

/** 
* Don't let anyone instantiate this class. 
* 
* @throws UnsupportedOperationException 
*    Always. 
*/ 
private StringValuedEnumReflect() { 
    throw new UnsupportedOperationException(
      "This class must not be instanciated."); 
} 

/** 
* All Enum constants (instances) declared in the specified class. 
* 
* @param enumClass 
*   Class to reflect 
* @return Array of all declared EnumConstants (instances). 
*/ 
private static <T extends Enum<T>> T[] getValues(Class<T> enumClass) { 
    return enumClass.getEnumConstants(); 
} 

/** 
* All possible string values of the string valued enum. 
* 
* @param enumClass 
*   Class to reflect. 
* @return Available string values. 
*/ 
public static <T extends Enum<T> & StringValuedEnum> String[] getStringValues(
     Class<T> enumClass) { 
    T[] values = getValues(enumClass); 
    String[] result = new String[values.length]; 
    for (int i = 0; i < values.length; i++) { 
     result[i] = values[i].getDbCode(); 
    } 
    return result; 
} 

/** 
* Name of the enum instance which hold the especified string value. If 
* value has duplicate enum instances than returns the first occurency. 
* 
* @param enumClass 
*   Class to inspect. 
* @param value 
*   String. 
* @return name of the enum instance. 
*/ 
public static <T extends Enum<T> & StringValuedEnum> String getNameFromValue(
     Class<T> enumClass, String value) { 
    T[] values = getValues(enumClass); 
    for (T v : values) { 
     if (v.getDbCode().equals(value)) { 
      return v.name(); 
     } 
    } 
    return ""; 
} 

}

類擴展EnhancedUserType：

//請注意，以getNameFromValue * ** * ** * ** *來電***

public class StringValuedEnumType<T extends Enum<T> & StringValuedEnum> 
    implements EnhancedUserType, ParameterizedType { 

/** 
* Enum class for this particular user type. 
*/ 
private Class<T> enumClass; 


/** Creates a new instance of ActiveStateEnumType */ 
public StringValuedEnumType() { 
} 

@SuppressWarnings("unchecked") 
@Override 
public void setParameterValues(Properties parameters) { 
    String enumClassName = parameters.getProperty("enumClass"); 
    try { 
     enumClass = (Class<T>) Class.forName(enumClassName) 
       .asSubclass(Enum.class).asSubclass(StringValuedEnum.class); // Validates 
                      // the 
                      // class 
                      // but 
                      // does 
                      // not 
                      // eliminate 
                      // the 
                      // cast 
    } catch (ClassNotFoundException cnfe) { 
     throw new HibernateException("Enum class not found", cnfe); 
    } 

} 

/** 
* The class returned by <tt>nullSafeGet()</tt>. 
* 
* @return Class 
*/ 
@SuppressWarnings("rawtypes") 
public Class returnedClass() { 
    return enumClass; 
} 

public int[] sqlTypes() { 
    return new int[] { Types.VARCHAR }; 
} 

public boolean isMutable() { 
    return false; 
} 

/** 
* Retrieve an instance of the mapped class from a JDBC resultset. 
* Implementors should handle possibility of null values. 
* 
* @param rs 
*   a JDBC result set 
* @param names 
*   the column names 
* @param owner 
*   the containing entity 
* @return Object 
* @throws HibernateException 
* @throws SQLException 
*/ 
@Override 
public Object nullSafeGet(ResultSet rs, String[] names, SessionImplementor session, Object owner) 
     throws HibernateException, SQLException { 
    String value = rs.getString(names[0]); 
    if (value == null) { // no default value 
     return null; 
    } 
    String name = getNameFromValue(enumClass, value); 
    Object res = rs.wasNull() ? null : Enum.valueOf(enumClass, name); 

    return res; 
} 

/** 
* Write an instance of the mapped class to a prepared statement. 
* Implementors should handle possibility of null values. A multi-column 
* type should be written to parameters starting from <tt>index</tt>. 
* 
* @param st 
*   a JDBC prepared statement 
* @param value 
*   the object to write 
* @param index 
*   statement parameter index 
* @param session 
*   session 
* @throws HibernateException 
* @throws SQLException 
*/ 
@SuppressWarnings("unchecked") 
@Override 
public void nullSafeSet(PreparedStatement st, Object value, int index, SessionImplementor session) 
     throws HibernateException, SQLException { 
    if (value == null) { 
     st.setNull(index, Types.CHAR); 
    } else { 
     st.setString(index, ((T) value).getDbCode()); 
    }  
} 

public Object assemble(Serializable cached, Object owner) 
     throws HibernateException { 
    return cached; 
} 

public Serializable disassemble(Object value) throws HibernateException { 
    return (Enum<?>) value; 
} 

public Object deepCopy(Object value) throws HibernateException { 
    return value; 
} 

public boolean equals(Object x, Object y) throws HibernateException { 
    return x == y; 
} 

public int hashCode(Object x) throws HibernateException { 
    return x.hashCode(); 
} 

public Object replace(Object original, Object target, Object owner) 
     throws HibernateException { 
    return original; 
} 

@SuppressWarnings("unchecked") 
public String objectToSQLString(Object value) { 
    return '\'' + ((T) value).getDbCode() + '\''; 
} 

@SuppressWarnings("unchecked") 
public String toXMLString(Object value) { 
    return ((T) value).getDbCode(); 
} 

public Object fromXMLString(String xmlValue) { 
    String name = getNameFromValue(enumClass, xmlValue); 
    return Enum.valueOf(enumClass, name); 
} 
} 

樣品實體類

@Entity 

@Table（名稱= 「TCSM_BUS_ENTY」） @DynamicUpdate 公共類SampleClient延伸的java.io.Serializable {

private static final long serialVersionUID = 1L; 

@Id 
@GeneratedValue(strategy = GenerationType.SEQUENCE) 
@Column(name = "SID") 
private Long id; 

@Column(name = "SAMPLE_NM") 
@Type(type = "com.sample.data.common.StringValuedEnumType", parameters = { @Parameter(name = "enumClass", value = "com.sample.data.model.types.BusinessType") }) 
private Sample sample; 
}