顯示所有列表查詢java hibernate

Question

我有此功能可在休眠狀態下查詢：

public List<TransactionQR> getAllTransaction() throws HibernateException {

        return this.session.createQuery("SELECT id FROM TransactionQR").list();
    }

然后成功在html中顯示如下數據：

[2, 3]

但是當我在SELECT中添加更多列時是這樣的：

public List<TransactionQR> getAllTransaction() throws HibernateException {

            return this.session.createQuery("SELECT id, codeqr FROM TransactionQR").list();
        }

結果顯示如下：

[Ljava.lang.Object;@25026824, [Ljava.lang.Object;@170b75f9]

什么是Ljava.lang.Object; @ 25026824？ 是返回對象，我可以處理它從列表轉換為json嗎？ 我有模型TransactionQR.java：

public class TransactionQR implements Serializable {
    private Long id;
    private String codeqr;
    private Date approvaltime;
    private String merchant;
    private String code_merchant;
    private Long amount;
    private Long saldoawal;
    private Integer tracenumber;
    private String state;
    private Date createdate;
    private Batch batch;

    public TransactionQR() {

    }

    public TransactionQR(Long id, String codeqr, Date approvaltime, String merchant, String code_merchant, Long amount,
            Long saldoawal, Integer tracenumber, String state, Date createdate, Batch batch) {
        super();
        this.id = id;
        this.codeqr = codeqr;
        this.approvaltime = approvaltime;
        this.merchant = merchant;
        this.code_merchant = code_merchant;
        this.amount = amount;
        this.saldoawal = saldoawal;
        this.tracenumber = tracenumber;
        this.state = state;
        this.createdate = createdate;
        this.batch = batch;
    }

    public Long getId() {
        return id;
    }
    public Date getApprovalTime() {
        return approvaltime;
    }

    public Batch getBatch() {
        return batch;
    }

    public void setBatch(Batch batch) {
        this.batch = batch;
    }

    public void setApprovalTime(Date approvalTime) {
        this.approvaltime = approvalTime;
    }
    public void setId(Long id) {
        this.id = id;
    }

    public Date getApprovaltime() {
        return approvaltime;
    }

    public void setApprovaltime(Date approvaltime) {
        this.approvaltime = approvaltime;
    }

    public String getCodeqr() {
        return codeqr;
    }

    public void setCodeqr(String codeqr) {
        this.codeqr = codeqr;
    }



    public String getMerchant() {
        return merchant;
    }

    public void setMerchant(String merchant) {
        this.merchant = merchant;
    }

    public String getCode_merchant() {
        return code_merchant;
    }

    public void setCode_merchant(String code_merchant) {
        this.code_merchant = code_merchant;
    }

    public Long getAmount() {
        return amount;
    }

    public void setAmount(Long amount) {
        this.amount = amount;
    }

    public Long getSaldoawal() {
        return saldoawal;
    }

    public void setSaldoawal(Long saldoawal) {
        this.saldoawal = saldoawal;
    }

    public Integer getTracenumber() {
        return tracenumber;
    }

    public void setTracenumber(Integer tracenumber) {
        this.tracenumber = tracenumber;
    }

    public String getState() {
        return state;
    }

    public void setState(String state) {
        this.state = state;
    }

    public Date getCreatedate() {
        return createdate;
    }

    public void setCreatedate(Date createdate) {
        this.createdate = createdate;
    }

}

結果是我想在列表中顯示數據庫中的所有數據

Answer 1

在第二種情況下，由於要選擇兩個屬性，因此session.createQuery（“”）。list返回一個對象數組List<Object[]> （ List<Object[]> ）的原因。 在列表的每個索引處，您將找到一個對象數組。 每個數組將有兩個索引。 第一個索引將提供id，第二個索引將提供codeqr。 因此，基本上，您需要遍歷該列表。 然后分別獲取每個值，如arr [0]，arr [1]。