SSH项目_02BaseDao完成分页功能供其他Dao继承

作者: 编程_书恨少 | 来源:发表于2018-08-31 16:32 被阅读0次

1. BaseDao的抽取和通用功能的实现

1.1 BaseDao

public interface BaseDao<T> {

    //增
    void save(T t);

    //删
    void delete(T t);

    //删
    void delete(Serializable id);

    //改
    void update(T t);

    //查 根据id查询
    T getById(Serializable id);

    //查 符合条件的总记录数
    Integer getTotalCount(DetachedCriteria dc);

    //查 查询分页列表数据
    List<T> getPageList(DetachedCriteria dc, Integer start, Integer pageSize);
}

1.1 BaseDaoImpl

public class BaseDaoImpl<T> extends HibernateDaoSupport implements BaseDao<T> {

    private Class clazz;

    public BaseDaoImpl() {

        //获得当前类型的带有泛型类型的父类
        ParameterizedType ptClass = (ParameterizedType) this.getClass().getGenericSuperclass();

        //获得运行期的泛型类型
        clazz = (Class) ptClass.getActualTypeArguments()[0];
    }

    @Override
    public void save(T t) {

        getHibernateTemplate().save(t);
    }

    @Override
    public void delete(T t) {

        getHibernateTemplate().delete(t);
    }

    @Override
    public void delete(Serializable id) {

        getHibernateTemplate().delete(getById(id));
    }

    @Override
    public void update(T t) {

        getHibernateTemplate().update(t);
    }

    @Override
    public T getById(Serializable id) {

        return (T) getHibernateTemplate().get(clazz, id);
    }

    @Override
    public Integer getTotalCount(DetachedCriteria dc) {

        //设置查询的聚合函数,总记录数
        dc.setProjection(Projections.rowCount());

        List<Long> list = (List<Long>) getHibernateTemplate().findByCriteria(dc);

        // 清空之前设置的聚合函数
        dc.setProjection(null);

        if (list != null && list.size() > 0) {

            Long count = list.get(0);

            return count.intValue();

        } else {

            return null;
        }
    }


    @Override
    public List<T> getPageList(DetachedCriteria dc, Integer start, Integer pageSize) {

        List<T> list = (List<T>) getHibernateTemplate().findByCriteria(dc, start, pageSize);

        return list;
    }
}

2. 封装PageBean

作用：将页面传入的参数进行统一的判断处理，并且将查询到的分页数据list也存储进PageBean的对象中，方便进行重定向或者转发

public class PageBean {

    //当前页数
    private Integer currentPage;
    //总记录数
    private Integer totalCount;
    //每页显示条数
    private Integer pageSize;
    //总页数
    private Integer totalPage;
    //分页列表数据
    private List list;


    public PageBean(Integer currentPage, Integer totalCount, Integer pageSize) {

        this.currentPage = currentPage;
        this.totalCount = totalCount;
        this.pageSize = pageSize;


        //如页面没有指定显示那一页.显示第一页.
        if(this.currentPage == null){
            this.currentPage = 1;
        }


        //如果每页显示条数没有指定,默认每页显示3条
        if(this.pageSize == null){
            this.pageSize = 10;
        }

        //计算总页数
        this.totalPage = (this.totalCount+this.pageSize-1)/this.pageSize;

        //判断当前页数是否超出范围
        //不能小于1
        if(this.currentPage < 1){
            this.currentPage = 1;
        }

        //不能大于总页数
        if(this.currentPage > this.totalPage){
            this.currentPage = this.totalPage;
        }

    }


    //计算起始索引
    public int getStart(){
        return (this.currentPage-1)*this.pageSize;
    }



    public Integer getCurrentPage() {
        return currentPage;
    }

    public void setCurrentPage(Integer currentPage) {
        this.currentPage = currentPage;
    }

    public Integer getTotalCount() {
        return totalCount;
    }

    public void setTotalCount(Integer totalCount) {
        this.totalCount = totalCount;
    }

    public Integer getPageSize() {
        return pageSize;
    }

    public void setPageSize(Integer pageSize) {
        this.pageSize = pageSize;
    }

    public Integer getTotalPage() {
        return totalPage;
    }

    public void setTotalPage(Integer totalPage) {
        this.totalPage = totalPage;
    }

    public List getList() {
        return list;
    }

    public void setList(List list) {
        this.list = list;
    }
}

3. 通过继承BaseDao和封装的PageBean完成客户列表的分页查询

3.1 CustomerAction处理请求

public class CustomerAction extends ActionSupport implements ModelDriven<Customer>{

    private Customer customer = new Customer();

    private CustomerService customerService;
    private Integer currentPage;
    private Integer pageSize;


    public String list() throws Exception {

        //封装离线查询对象
        DetachedCriteria detachedCriteria = DetachedCriteria.forClass(Customer.class);

        //判断并封装参数
        if (StringUtils.isNotBlank(customer.getCust_name())) {

            detachedCriteria.add(Restrictions.like("cust_name", "%"+customer.getCust_name()+"%"));
        }

        //1. 调用Service查询分页数据(PageBean)
        PageBean pageBean = customerService.getPageBean(detachedCriteria, currentPage, pageSize);

        //2. 将PageBean放入request域,转发到列表页面显示
        ActionContext.getContext().put("pageBean", pageBean);

        return "list";
    }



    public void setCustomerService(CustomerService customerService) {
        this.customerService = customerService;
    }

    public void setCurrentPage(Integer currentPage) {
        this.currentPage = currentPage;
    }

    public Integer getCurrentPage() {
        return currentPage;
    }

    public Integer getPageSize() {
        return pageSize;
    }

    public void setPageSize(Integer pageSize) {
        this.pageSize = pageSize;
    }

    @Override
    public Customer getModel() {
        return customer;
    }
}

3.2 CustomerService和CustomerServiceImpl


public interface CustomerService {

    // 分页方法
    PageBean getPageBean(DetachedCriteria dc, Integer currentPage, Integer pageSize);

}

@Transactional(isolation = Isolation.REPEATABLE_READ, propagation = Propagation.REQUIRED, readOnly = true)
public class CustomerServiceImpl implements CustomerService {

    CustomerDao customerDao;


    @Override
    public PageBean getPageBean(DetachedCriteria dc, Integer currentPage, Integer pageSize) {

        //1 调用Dao查询总记录数
        Integer totalCount = customerDao.getTotalCount(dc);

        //2 创建PageBean对象
        PageBean pageBean = new PageBean(currentPage, totalCount, pageSize);

        //3 调用Dao查询分页列表数据
        List<Customer> list = customerDao.getPageList(dc, pageBean.getStart(), pageBean.getPageSize());

        pageBean.setList(list);

        return pageBean;
    }



    public void setCustomerDao(CustomerDao customerDao) {
        this.customerDao = customerDao;
    }
}

3.3 通过继承BaseDao来实现CustomerDao

public interface CustomerDao extends BaseDao<Customer> {
}

public class CustomerDaoImpl extends BaseDaoImpl<Customer> implements CustomerDao {
}

4. 配置文件最终形态

4.1 struts.xml

<struts>

    <!--spring负责装配Action依赖属性，默认struts已经打开了-->
    <!--<constant name="struts.objectFactory.spring.autoWire" value="name"></constant>-->

    <!--将action的创建交给spring容器-->
    <constant name="struts.objectFactory" value="spring"></constant>

    <!-- 整合方案1:class属性上仍然配置action的完整类名
                struts2仍然创建action,由spring负责组装Action中的依赖属性
    -->
    <package name="crm" namespace="/" extends="struts-default">

        <global-exception-mappings>
            <exception-mapping exception="java.lang.RuntimeException" result="error"></exception-mapping>
        </global-exception-mappings>
        <!--
            整合方案2:class属性上填写spring中action对象的BeanName
                完全由spring管理action生命周期,包括Action的创建
                注意:需要手动组装依赖属性
          -->
        <action name="UserAction_*" class="userAction" method="{1}" >
            <result name="toHome" type="redirect" >/index.htm</result>
            <result name="error" >/login.jsp</result>
        </action>

        <action name="CustomerAction_*" class="customerAction" method="{1}">
            <result name="list" type="dispatcher">/jsp/customer/list.jsp</result>
        </action>
    </package>

</struts>

4.2 applicationContext.xml

<!--==========================================================================================-->

    <!--读取db.properties文件-->
    <context:property-placeholder location="classpath:db.properties"/>

    <!--配置c3p0数据库连接池-->
    <bean name="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
        <property name="driverClass" value="${jdbc.driverClass}"></property>
        <property name="user" value="${jdbc.user}"></property>
        <property name="password" value="${jdbc.password}"></property>
    </bean>



    <!--=========================================== struts2配置 ===============================================-->

    <!--将sessionFactory配置到spring容器中-->
    <!-- 加载配置方案2:在spring配置中放置hibernate配置信息 -->
    <bean name="sessionFactory" class="org.springframework.orm.hibernate5.LocalSessionFactoryBean">

        <!-- 将连接池注入到sessionFactory, hibernate会通过连接池获得连接 -->
        <property name="dataSource" ref="dataSource"></property>
        
        <!-- 配置hibernate基本信息 -->
        <property name="hibernateProperties">
            <props>
                <!--  必选配置 -->
                <prop key="hibernate.dialect">org.hibernate.dialect.MySQLDialect</prop>

                <!--可选配置-->
                <prop key="hibernate.show_sql">true</prop>
                <prop key="hibernate.format_sql">true</prop>
                <prop key="hibernate.hbm2ddl.auto">update</prop>
            </props>
        </property>

        <!-- 引入orm元数据,指定orm元数据所在的包路径,spring会自动读取包中的所有配置 -->
        <property name="mappingDirectoryLocations" value="classpath:domain"></property>
    </bean>


    <!--==========================================================================================-->

    <!--配置核心事务管理器-->
    <bean name="transactionManager" class="org.springframework.orm.hibernate5.HibernateTransactionManager">
        <property name="sessionFactory" ref="sessionFactory"></property>
    </bean>

    <!--配置通知-->
    <!--<tx:advice id="txAdvice" transaction-manager="transactionManager">-->
        <!--<tx:attributes>-->
            <!--<tx:method name="save*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />-->
            <!--<tx:method name="persist*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />-->
            <!--<tx:method name="update*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />-->
            <!--<tx:method name="modify*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />-->
            <!--<tx:method name="delete*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />-->
            <!--<tx:method name="remove*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="false" />-->
            <!--<tx:method name="get*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="true" />-->
            <!--<tx:method name="find*" isolation="REPEATABLE_READ" propagation="REQUIRED" read-only="true" />-->
        <!--</tx:attributes>-->
    <!--</tx:advice>-->

    <!--&lt;!&ndash;配置将通知织入目标对象&ndash;&gt;-->
    <!--<aop:config>-->
        <!--<aop:pointcut expression="execution(* serviceImpl.*ServiceImpl.*(..))" id="txPc"/>-->
        <!--<aop:advisor advice-ref="txAdvice" pointcut-ref="txPc" />-->
    <!--</aop:config>-->


    <!--开启注解事务-->
    <tx:annotation-driven transaction-manager="transactionManager"/>

    <!--==========================================================================================-->

    <!--==================================== action ===========================================-->
    <bean name="userAction" class="web.UserAction" scope="prototype">
        <property name="userService" ref="userService"></property>
    </bean>

    <bean name="customerAction" class="web.CustomerAction" scope="prototype">
        <property name="customerService" ref="customerService"></property>
    </bean>


    <!--==================================== service ===========================================-->
    <bean name="userService" class="serviceImpl.UserServiceImpl">
        <property name="userDao" ref="userDao"></property>
    </bean>

    <bean name="customerService" class="serviceImpl.CustomerServiceImpl">
        <property name="customerDao" ref="customerDao"></property>
    </bean>


    <!--==================================== dao ===========================================-->
    <bean name="userDao" class="daoImpl.UserDaoImpl">
        <property name="sessionFactory" ref="sessionFactory"></property>
    </bean>

    <bean name="customerDao" class="daoImpl.CustomerDaoImpl">
        <property name="sessionFactory" ref="sessionFactory"></property>
    </bean>

</beans>

SSH项目_02BaseDao完成分页功能供其他Dao继承

1. BaseDao的抽取和通用功能的实现

1.1 BaseDao

1.1 BaseDaoImpl

2. 封装PageBean

3. 通过继承BaseDao和封装的PageBean完成客户列表的分页查询

3.1 CustomerAction处理请求

3.2 CustomerService和CustomerServiceImpl

3.3 通过继承BaseDao来实现CustomerDao

4. 配置文件最终形态

4.1 struts.xml

4.2 applicationContext.xml

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