hibernate查询表的部分属性
由于一个表中含有比较占内存的字段，当查询的结果比较大时，可能会造成内存泄漏，所以想在查询的时候不加载那个字段，具体类如下：
import java.io.Serializable;import java.util.Date;import javax.persistence.Column;import javax.persistence.Entity;import javax.persistence.GeneratedValue;import javax.persistence.Id;import javax.persistence.JoinColumn;import javax.persistence.ManyToOne;import javax.persistence.Table;import org.hibernate.annotations.Cache;import org.hibernate.annotations.CacheConcurrencyStrategy;import org.hibernate.annotations.GenericGenerator;import org.hibernate.annotations.Parameter;import org.hibernate.search.annotations.DocumentId;/** * 网上记账实体类 * @since 2011-3-4 * @author * @comment */@Entity@Table(name = "TOOLACCOUNT")@org.hibernate.annotations.Entity(dynamicUpdate = true, dynamicInsert = true)@Cache(usage = CacheConcurrencyStrategy.READ_WRITE)public class ToolAccount implements Serializable {private static final long serialVersionUID = 1L;/** 主键 * */@Id@Column(name = "TOOLACCOUNTPK", length = 19)@GeneratedValue(generator = "custom-id")@GenericGenerator(name = "custom-id", strategy = "lab24.util.TableKeyGenerator", parameters = {@Parameter(name = "table", value = "KEYGENERATOR_TABLE"),@Parameter(name = "pkColumnName", value = "G_KEY"),@Parameter(name = "pkColumnValue", value = "TOOLACCOUNT_PK"),@Parameter(name = "valueColumnName", value = "G_VALUE"),@Parameter(name = "allocationSize", value = "1") })@DocumentIdprivate long toolAccountPK;private String title;//名称private Date createDate;//创建日期private double money ;//金额private String content;//内容private int inOrOut;//收入还是支出 0:收入 1：支出private String inOrOutType;//收入与支出的明线条目/** 关联用户 * */@ManyToOne(optional = false)@JoinColumn(name = "USERPK", nullable = false)private User user;public double getMoney() {return money;}public void setMoney(double money) {this.money = money;}public int getInOrOut() {return inOrOut;}public void setInOrOut(int inOrOut) {this.inOrOut = inOrOut;}public String getInOrOutType() {return inOrOutType;}public void setInOrOutType(String inOrOutType) {this.inOrOutType = inOrOutType;}public long getToolAccountPK() {return toolAccountPK;}public void setToolAccountPK(long toolAccountPK) {this.toolAccountPK = toolAccountPK;}public Date getCreateDate() {return createDate;}public void setCreateDate(Date createDate) {this.createDate = createDate;}public String getTitle() {return title;}public void setTitle(String title) {this.title = title;}public String getContent() {return content;}public void setContent(String content) {this.content = content;}public User getUser() {return user;}public void setUser(User user) {this.user = user;}}?这里的content是比较大的信息的字段，而作统计账单信息时，它是用不上的，所以想查询的时候不要这个字段，这在hibernate 也是可以做到的，这里是使用一个新的类来存放查询的结果，因为hibernate是以封装好的对象返回来的，所以这里要新建一个对象，这个和