例外：java.io.NotSerializableException：org.springframework.jdbc.datasource.DriverManagerDataSource

Question

我创建了一个spring项目（Spring 4.0.2）。我提出了所需的文件：

spring.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">

    <bean id="employeeDAO" class="com.journaldev.spring.jdbc.dao.EmployeeDAOImpl">
        <property name="dataSource" ref="dataSource" />
    </bean>

    <bean id="employeeDAOJDBCTemplate" class="com.journaldev.spring.jdbc.dao.EmployeeDAOJDBCTemplateImpl">
        <property name="dataSource" ref="dataSource" />
    </bean>

    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.microsoft.sqlserver.jdbc.SQLServerDriver" />
        <property name="url" value="jdbc:sqlserver://localhost:1433;database=springdb"/>
        <property name="username" value="lm" />
        <property name="password" value="pp" />
    </bean>

</beans>

Employee.java

@Entity
@Table(name="Employee")
public class Employee {
    @Id      
    @GeneratedValue(strategy=GenerationType.IDENTITY)
    @Column(name = "id", unique = true, nullable = false)
    private int id;

    @Column(name = "name")
    private String name;

    @Column(name = "role")
    private String role;

    // with getters, setters, default constructor, constructor using fields
}

EmployeeDAO.java

public interface EmployeeDAO 
{
    public List<Employee> getAll();
}

EmployeeDAOImpl.java

public class EmployeeDAOImpl implements EmployeeDAO {
    private DataSource dataSource;

    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }

    @Override
    public List<Employee> getAll() {
        String query = "select id, name, role from Employee";
        List<Employee> empList = new ArrayList<Employee>();
        Connection con = null;
        PreparedStatement ps = null;
        ResultSet rs = null;
        try{
            con = dataSource.getConnection();
            ps = con.prepareStatement(query);
            rs = ps.executeQuery();
            while(rs.next()){
                Employee emp = new Employee();
                emp.setId(rs.getInt("id"));
                emp.setName(rs.getString("name"));
                emp.setRole(rs.getString("role"));
                empList.add(emp);
            }
        }catch(SQLException e){
            e.printStackTrace();
        }finally{
            try {
                rs.close();
                ps.close();
                con.close();
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        return empList;
    }
}

EmployeeDAOJDBCTemplateImpl.java

public class EmployeeDAOJDBCTemplateImpl implements EmployeeDAO,Serializable {
    private DataSource dataSource;

    public void setDataSource(DataSource dataSource) {
        this.dataSource = dataSource;
    }

    @Override
    public List<Employee> getAll() {
        String query = "select id, name, role from Employee";
        JdbcTemplate jdbcTemplate = new JdbcTemplate(dataSource);
        List<Employee> empList = new ArrayList<Employee>();

        List<Map<String,Object>> empRows = jdbcTemplate.queryForList(query);

        for(Map<String,Object> empRow : empRows){
            Employee emp = new Employee();
            emp.setId(Integer.parseInt(String.valueOf(empRow.get("id"))));
            emp.setName(String.valueOf(empRow.get("name")));
            emp.setRole(String.valueOf(empRow.get("role")));
            empList.add(emp);
        }
        return empList;
    }
}

要调用的bean以提取员工列表 DataModelD.java ：

@ManagedBean
@ViewScoped
public class DataModelD implements Serializable
{
    private List<Employee> list;
    private Employee employee;
    private EmployeeDAO eDao;

    @PostConstruct
    public void init() 
    {
    System.out.println("-----------------------------BEGIN List");
ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("spring.xml");
eDao = ctx.getBean("employeeDAOJDBCTemplate", EmployeeDAO.class);
    employee = new Employee();
    list = eDao.getAll();
    System.out.println("---------------------------------------List size= " + list.size());
    }
}

运行后（显示员工列表），将显示以下异常：

08:14:46,222 INFO  [org.jboss.as.server] (DeploymentScanner-threads - 2) JBAS018559: Deployed "HiSpring.war"
08:15:29,271 INFO  [stdout] (http-localhost-127.0.0.1-8080-1) -----------------------------BEGIN List

08:15:29,529 INFO  [org.springframework.context.support.ClassPathXmlApplicationContext] (http-localhost-127.0.0.1-8080-1) Refreshing org.springframework.context.support.ClassPathXmlApplicationContext@ca34ed: startup date [Wed Aug 17 08:15:29 GMT-08:00 2016]; root of context hierarchy
08:15:29,591 INFO  [org.springframework.beans.factory.xml.XmlBeanDefinitionReader] (http-localhost-127.0.0.1-8080-1) Loading XML bean definitions from class path resource [spring.xml]
08:15:29,718 INFO  [org.springframework.jdbc.datasource.DriverManagerDataSource] (http-localhost-127.0.0.1-8080-1) Loaded JDBC driver: com.microsoft.sqlserver.jdbc.SQLServerDriver
08:15:30,736 INFO  [stdout] (http-localhost-127.0.0.1-8080-1) ---------------------------------------List size= 5

08:15:30,832 SEVERE [javax.enterprise.resource.webcontainer.jsf.application] (http-localhost-127.0.0.1-8080-1) Error Rendering View[/sarsoura/list.xhtml]: java.io.NotSerializableException: org.springframework.jdbc.datasource.DriverManagerDataSource
    at java.io.ObjectOutputStream.writeObject0(Unknown Source) [rt.jar:1.7.0_55]
    at java.io.ObjectOutputStream.defaultWriteFields(Unknown Source) [rt.jar:1.7.0_55]

您对这个问题有什么想法吗？。非常感谢。