package net.jeffrey.hibernate.history;import java.io.Serializable;import java.text.DateFormat;import java.util.Date;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.Enumerated;import javax.persistence.NamedQueries;import javax.persistence.NamedQuery;import javax.persistence.Temporal;import javax.persistence.TemporalType;import net.jeffrey.hibernate.AbstractEntity;/** * 操作日志的條目 * @author jeffrey */@Entity@NamedQueries({    // 命名查詢，根據實體查詢與其關聯的審計日志記錄，注意這里審計日志和被審計實體并沒有物理關聯（數據庫約束），即使實體被刪除，仍然可以根據實體id訪問審計日志。    @NamedQuery(name = "HistoryEntry.findByEntity", query = "select h from HistoryEntry h where entity = :entity and entityId = :entityId order by timestamp asc")})public class HistoryEntry extends AbstractEntity implements Serializable {    private static final long serialVersionUID = 9025279546306024660L;        /* 操作的時間 */    @Temporal(TemporalType.TIMESTAMP)    @Column(name = "hs_timestamp")    private Date timestamp;        /* 操作的類型（枚舉型：新建、更新、刪除） */    @Enumerated(javax.persistence.EnumType.STRING)    private OperationType operationType;        /* 被操作的實體類型 */    private Class entity;        /* 被操作實體的主鍵id */    @Column(name = "entity_id")    private Integer entityId;        /* 操作描述 */    private String description;        /* 被操作的屬性 */    private String property;        /* 操作前的值 */    private String previousValue;        /* 更新值 */    private String newValue;    public HistoryEntry() {    }    public String getDescription() {        return description;    }    public void setDescription(String description) {        this.description = description;    }    public Class getEntity() {        return entity;    }    public void setEntity(Class entity) {        this.entity = entity;    }    public Integer getEntityId() {        return entityId;    }    public void setEntityId(Integer entityId) {        this.entityId = entityId;    }    public String getNewValue() {        return newValue;    }    public void setNewValue(String newValue) {        this.newValue = newValue;    }    public OperationType getOperationType() {        return operationType;    }    public void setOperationType(OperationType operationType) {        this.operationType = operationType;    }    public String getPreviousValue() {        return previousValue;    }    public void setPreviousValue(String previousValue) {        this.previousValue = previousValue;    }    public String getProperty() {        return property;    }    public void setProperty(String property) {        this.property = property;    }    public Date getTimestamp() {        return timestamp;    }    public void setTimestamp(Date timestamp) {        this.timestamp = timestamp;    }        public void setHistorizableEntity(Historizable entity) {        this.setEntity(entity.getClass());        this.setEntityId(entity.getId());        this.setDescription(entity.toString());    }        @Override    public String toString() {        return "History[" + DateFormat.getDateTimeInstance().format(timestamp) + ", " + operationType + ", " + entity.getSimpleName() + "," + id + " " + property + "]";    }    @Override    public boolean equals(Object obj) {        if (obj == null) {            return false;        }        if (getClass() != obj.getClass()) {            return false;        }        final HistoryEntry other = (HistoryEntry) obj;        return this.getId().equals(other.getId());    }    @Override    public int hashCode() {        int hash = 5;        hash = 47 * hash + id;        return hash;    }}