ibatis这问题哪里错了，查不出数据

public class Product{
	private int pid;
	private String productName;
	private String author;
	private double price;
	private Date publishTime;
	private String descript;
	private String imgSrc;
	private String remark;
	private Category category = new Category();

	public int getPid() {
		return pid;
	}

	public void setPid(int pid) {
		this.pid = pid;
	}

	public String getProductName() {
		return productName;
	}

	public void setProductName(String productName) {
		this.productName = productName;
	}

	public String getAuthor() {
		return author;
	}

	public void setAuthor(String author) {
		this.author = author;
	}

	public double getPrice() {
		return price;
	}

	public void setPrice(double price) {
		this.price = price;
	}

	public Date getPublishTime() {
		return publishTime;
	}

	public void setPublishTime(Date publishTime) {
		this.publishTime = publishTime;
	}

	public String getDescript() {
		return descript;
	}

	public void setDescript(String descript) {
		this.descript = descript;
	}

	public String getImgSrc() {
		return imgSrc;
	}

	public void setImgSrc(String imgSrc) {
		this.imgSrc = imgSrc;
	}

	public String getRemark() {
		return remark;
	}

	public void setRemark(String remark) {
		this.remark = remark;
	}

	public Category getCategory() {
		return category;
	}
	public void setCategory(Category category) {
		this.category = category;
	}
}

<sqlMap namespace="Product">
    <typeAlias alias="product" type="org.bs.pojo.Product" />
    <typeAlias alias="category" type="org.bs.pojo.Category" />

    <resultMap class="category" id="categoryMap">
        <result property="cid" column="cid" />
        <result property="categoryName" column="categoryName" />
    </resultMap>
    <resultMap class="product" id="productMap">
        <result property="pid" column="pid" />
        <result property="productName" column="productName" />
        <result property="author" column="author" />
        <result property="price" column="price" />
        <result property="publishTime" column="publishTime" />
        <result property="descript" column="descript" />
        <result property="imgSrc" column="imgSrc" />
        <result property="remark" column="remark" />
        <result property="category" column="cid" select="getCategoryById" />
    </resultMap>
    <select id="getCategoryById" resultClass="category"> 
        select cid,categoryName from category
    </select>
    <select id="getAllProduct" resultClass="product">
        select
        *
        from
        product
    </select>
</sqlMap>

public class ProductDaoImpl extends SqlMapClientDaoSupport implements
        IProductDao {
    public List<Product> getAllProduct() {
        List<Product> listProduct = getSqlMapClientTemplate().queryForList(
                "getAllProduct");
        return listProduct;
    }

}

@Test
	public void testProduct() {
		IProductBiz u = (IProductBiz) GetBean.getBean("productBiz");
		try {
			List<Product> list = u.getAllProduct();
			for (int i = 0; i < list.size(); i++) {
				Product p = list.get(i);
				System.out.println(p.getProductName()+ p.getCategory().getCid());
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
	}