Question

我一直在尝试通过ArrayList在Servlet的帮助下在JSP中打印ResultSet。JDBC部分似乎没问题.ArrayList可以在JSP中获取并且可以打印。但是当我想要迭代时列表传递给带有<c:forEach>标记的JSP，它说的是我的bean类＆＃39; PureJavaClasses.employeeClass＆＃39;没有属性＆＃39; Id＆＃39;。我已经尝试过在SO上发布了一系列不同的解决方案，但都是徒劳的。我不知道该怎么做。我是JavaEE的初学者。

这是我的Bean类：

public class employeeClass implements java.io.Serializable {
private int id;
private String name;
private String job;
private int subjectId;
private int salary;

public employeeClass() {

}

public int getId() {
    return id;
}

public void setId(int id) {
    this.id = id;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getJob() {
    return job;
}

public void setJob(String job) {
    this.job = job;
}

public int getSubjectid() {
    return subjectId;
}

public void setSubjectid(int subjectId) {
    this.subjectId = subjectId;
}

public int getSalary() {
    return salary;
}

public void setSalary(int salary) {
    this.salary = salary;
}

@Override
public String toString() {
    return  "id=" + id +
            ", name=" + name +
            ", job=" + job +
            ", subjectId=" + subjectId +
            ", salary=" + salary;
}
}

这是servlet：

private void show_table(HttpServletRequest request,HttpServletResponse response){
    Connection connection = ServletLogin.connection;
    String query = "SELECT * FROM `dog`.`employee`";
    ArrayList<employeeClass> list = new ArrayList<>();
    try {
        PreparedStatement pst = connection.prepareStatement(query);
        ResultSet rs = pst.executeQuery();
        while(rs.next()){
            employeeClass obj2 = new employeeClass();
            obj2.setId(rs.getInt("ID"));
            obj2.setName(rs.getString("Name"));
            obj2.setJob(rs.getString("Job_Designation"));
            obj2.setSubjectid(rs.getInt("Subject ID"));
            obj2.setSalary(rs.getInt("Salary"));
            list.add(obj2);
        }
    } catch (SQLException e) {
        e.printStackTrace();
    }
    request.setAttribute("listEmp",list);
    try {
        request.getRequestDispatcher("/Pages/EmployeeTable.jsp").forward(request,response);
    } catch (ServletException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

这是我的EmployeeTable.jsp：

    <%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<%@ page import="java.util.ArrayList"%>
<html>

<head>
    <title>Employee List</title>
</head>
<body>
<% ArrayList list1 =(ArrayList) request.getAttribute("listEmp"); %>
<%=list1%>
    <table>
        <th>ID</th>
        <th>Name</th>
        <th>Job Designation</th>
        <th>Subject ID</th>
        <th>Salary</th>
        <c:forEach items="${listEmp}" var="list">
            <tr>
                <td><c:out value="${list.Id}"/></td>
                <td><c:out value="${list.name}"/></td>
                <td><c:out value="${list.job}"/></td>
                <td><c:out value="${list.subjectId}"/></td>
                <td><c:out value="${list.salary}"/></td>
            </tr>
        </c:forEach>
    </table>
</body>
</html>

这是我的web.xml：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
    <servlet>
        <servlet-name>ServletLogin</servlet-name>
        <servlet-class>ServletLogin</servlet-class>
    </servlet>
    <servlet>
        <servlet-name>ServletEmployee</servlet-name>
        <servlet-class>ServletEmployee</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>ServletLogin</servlet-name>
        <url-pattern>/ServletLogin</url-pattern>
    </servlet-mapping>
    <servlet-mapping>
        <servlet-name>ServletEmployee</servlet-name>
        <url-pattern>/ServletEmployee</url-pattern>
    </servlet-mapping>
    <session-config>
        <session-timeout>30</session-timeout>
    </session-config>

</web-app>

Answer 1

我认为您需要通过提供正确的名称来解决问题。就像使用id而不是Id等那样应该解决它。

<td><c:out value="${list.id}"/></td>

javax.el.PropertyNotFoundException：类＆＃39; PureJavaClasses.employeeClass＆＃39;没有财产＆＃39; Id＆＃39;

1 个答案: