Java Blob图像未显示在jsp页面[struts 1]中

我使用的是netbeans 6.9，我是struts 1.3.8的初学者，不知道如何在jsp页面中显示产品图像。我在web文件夹下的images文件夹中添加了图像，并将图像名称作为blob存储在数据库中，当我从数据库中检索图像时，它只打印图像的名称

这是jsp页面：

<html:form action="/addToCartAction">
        <span style='color:red'><html:errors property="SQL" />
            <html:errors property="SQLException" /></span>
        <table border="0">
            <thead>
                <tr>
                    <th></th>
                    <th></th>
                </tr>
            </thead>
            <tbody>
                <tr>
                    <td rowspan="6"><bean:write name="userHomeForm" property="itemImage" /></td>
                    <td><bean:write name="userHomeForm" property="itemName" />

                    </td>
                </tr>
                <tr>
                    <td>item in stock: <bean:write name="userHomeForm" property="itemQyt" />

                    </td>
                </tr>
                <tr>
                    <td>AED<bean:write name="userHomeForm" property="itemPrice" /></td>
                </tr>
                <tr>
                    <td><bean:write name="userHomeForm" property="itemDesc" /></td>
                </tr>
                <tr>
                    <td><html:text property="number" value="" size="3"/>&nbsp;
                        <input type="hidden" name="itemID" value="${userHomeForm.itemID}"/>
                        <input type="hidden" name="itemQyt" value="${userHomeForm.itemQyt}"/>
                        <html:submit value="add to cart"/></td>                        
                </tr>
                <tr>
                    <td><span style='color:red'><html:errors property="Qyt"/><html:errors property="OverQyt"/></span></td>
                </tr>

            </tbody>
        </table>


    </html:form>

这就是行动：

public class userHomeAction extends org.apache.struts.action.Action {

/* forward name="success" path="" */
private static final String SUCCESS = "success";
private final static String FAILURE = "failure";
// Initialize SQL connection equal null
private Connection con = null;
private ResultSet rst = null;
private ResultSet rs = null;

/**
 * This is the action called from the Struts framework.
 * @param mapping The ActionMapping used to select this instance.
 * @param form The optional ActionForm bean for this request.
 * @param request The HTTP Request we are processing.
 * @param response The HTTP Response we are processing.
 * @throws java.lang.Exception
 * @return
 */
@Override
public ActionForward execute(ActionMapping mapping, ActionForm form,
        HttpServletRequest request, HttpServletResponse response)
        throws Exception {
    //Initilized Action error
    ActionErrors errors = new ActionErrors();
    // set the session on in the page
    HttpSession session = request.getSession(true);
    //Call userHomeForm Instance here
    userHomeForm formBean = (userHomeForm) form;
    // extract user data
    String category = formBean.getCategory();
    String brand = formBean.getBrand();

    //Set up flag message
    boolean searchFlag = false;

    // perform validation
    if (category == null ||         // category parameter does not exist
        category.equals("") ||      // category parameter is empty
        category.length()< 1){      // category parameter is empty
        errors.add("category", new ActionMessage("errors.category.required"));
    }
    if (brand != null &&            // brand parameter does not exist
        brand.equals("") &&         // brand parameter is empty)
        brand.length()< 1) {        // brand parameter is empty)
        errors.add("brand", new ActionMessage("errors.brand.required"));
    }
    //Save error messages keys into the appropriate HTTP request attribute for use by the <html:errors> tag
    saveErrors(request, errors);
    //Check- is errors empty
    if (errors.isEmpty()) {
        searchFlag = true;

        // start Viewing userHome
        System.out.println("////////////////////////// start Viewing userHome  /////////////////////////");

    } else {
        searchFlag = false;
    }

    // Now Start communicate with database
    try {
        Class.forName("com.mysql.jdbc.Driver").newInstance();
        con = DriverManager.getConnection("jdbc:mysql://localhost:3306/gsm", "root", "root");
        //ArrayList<String[]> result = new ArrayList<String[]>();
        PreparedStatement ps = (PreparedStatement) con.prepareStatement("select * from item where categoryID=? and brandID=?");
        ps.setString(1, category);
        ps.setString(2, brand);
        rs = ps.executeQuery();
        Blob img= null;
        byte[]imgData= null;
        int columnCount = rs.getMetaData().getColumnCount();            
        int num = 0;
        if (rs != null) // Succes
        {
            while (rs.next()) {
                num++;
                searchFlag = true;
                int categoryID = rs.getInt("categoryID");
                int brandID = rs.getInt("brandID");
                int itemID = rs.getInt("itemID");
                int itemQyt = rs.getInt("itemQyt");
                int itemPrice = rs.getInt("itemPrice");
                String itemName = rs.getString("itemName");
                String itemDesc = rs.getString("itemDesc");
                String itemImage = rs.getString("itemImage");
                formBean.setBrandID(brandID);
                formBean.setCategoryID(categoryID);
                formBean.setItemDesc(itemDesc);
                formBean.setItemID(itemID);
                formBean.setItemImage(itemImage);
                formBean.setItemName(itemName);
                formBean.setItemPrice(itemPrice);
                formBean.setItemQyt(itemQyt);
                //// check out
                System.out.println("The item is from the category which its ID is : " + categoryID + " and brand with id :" + brandID + " and the item id is : " + itemID + " and with name : " + itemName + " and its price is : " + itemPrice + " with that much quantity : " + itemQyt + " and its description is : " + itemDesc);

            }                               
        }                       
    } catch (Exception ex) {
        errors.add("SQLException", new ActionMessage("errors.SQLException"));
        throw new SQLException(ex.fillInStackTrace());
    }
    //Close SQL server connection
    try {
        if (con != null) {
            con.close();
        }
    } catch (SQLException e) {
        throw new SQLException(e.getSQLState() + e.fillInStackTrace());
    }
    //Save error messages keys into the appropriate HTTP request attribute for use by the <html:errors> tag
    saveErrors(request, errors);
    if (errors.isEmpty()) {
        searchFlag = true;
    } else {
        searchFlag = false;
    }

    if (searchFlag) {
    return mapping.findForward(SUCCESS);
    } else {

        return mapping.findForward(FAILURE);
    }

}

---

}如果要显示图像，必须使用img标签：

图像的名称在表单中，因此您必须根据此属性动态生成路径：

<img src="${pageContext.request.contextPath}/${userHomeForm.itemImage}"/>

我不知道为什么要使用blob来存储图像名，而不是使用varchar。

我刚刚添加了路径

<img src="thePathOfTheImage" />

<img src="${pageContext.request.contextPath}/${userHomeForm.itemImage}"/>