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struts+spring+hibernate 的 web 應用 < 一 > 架構搭建

struts+spring+hibernate 的 web 應用 < 二 > Dao 層代碼編寫

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現(xiàn)在開始編寫 Service 層代碼：

在 com.game.products.services.iface 包中新建 ProductsService 接口，代碼如下：

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package ?com.game.products.services.iface;

import ?java.util.List;

import ?com.game.products.model.Products;

public ? interface ?ProductsService? {
???? void ?addProduct(Products?pd); // 添加記錄
???? void ?deleteProduct(Products?pd); // 刪除記錄????
????List?getProducts(); // 獲得所有記錄
???? int ?getRows();; // 獲得總行數(shù)
????List?getProducts( int ?pageSize,? int ?startRow)?; // 獲得一段記錄
????Products?getProduct(String?gameId); // 根據(jù)ID獲得記錄
????String?getMaxID(); // 獲得最大ID值
???? void ?updateProductd(Products?pd); // 修改記錄
????List?queryProducts(String?fieldname,String?value); // 根據(jù)條件查詢的所有記錄
???? int ?getRows(String?fieldname,String?value); // 獲得總行數(shù)
????List?queryProducts(String?fieldname,String?value, int ?pageSize,? int ?startRow); // 根據(jù)條件查詢的一段記錄
}

在 com.game.products.services 包中新建 ProductsServiceImp 類，這個類實現(xiàn)了 ProductsService 接口，代碼如下：

package ?com.game.products.services;

import ?java.util.List;

import ?com.game.products.dao.iface.ProductsDao;
import ?com.game.products.model.Products;
import ?com.game.products.services.iface.ProductsService;

public ? class ?ProductsServiceImp? implements ?ProductsService {
???? private ?ProductsDao?productsDao;
????
???? public ?ProductsServiceImp() {}
????
???? /**?*/ /**
?????*?函數(shù)說明：添加信息
?????*?參數(shù)說明：對象?
?????*?返回值：
????? */
???? public ? void ?addProduct(Products?pd)? {
????????productsDao.addProduct(pd);
????}

???? /**?*/ /**
?????*?函數(shù)說明：刪除信息
?????*?參數(shù)說明：?對象
?????*?返回值：
????? */
???? public ? void ?deleteProduct(Products?pd)? {
????????productsDao.deleteProduct(pd);
????}

???? /**?*/ /**
?????*?函數(shù)說明：獲得所有的信息
?????*?參數(shù)說明：?
?????*?返回值：信息的集合
????? */
???? public ?List?getProducts()? {
???????? return ?productsDao.getProducts();
????}
????
???? /**?*/ /**
?????*?函數(shù)說明：獲得總行數(shù)
?????*?參數(shù)說明：?
?????*?返回值：總行數(shù)
????? */
???? public ? int ?getRows()? {
???????? return ?productsDao.getRows();
????}
????
???? /**?*/ /**
?????*?函數(shù)說明：獲得一段信息
?????*?參數(shù)說明：?
?????*?返回值：信息的集合
????? */
???? public ?List?getProducts( int ?pageSize,? int ?startRow)? {
???????? return ?productsDao.getProducts(pageSize,?startRow);
????}

???? /**?*/ /**
?????*?函數(shù)說明：獲得一條的信息
?????*?參數(shù)說明：?ID
?????*?返回值：對象
????? */
???? public ?Products?getProduct(String?gameId)? {
???????? return ?productsDao.getProduct(gameId);
????}

???? /**?*/ /**
?????*?函數(shù)說明：獲得最大ID
?????*?參數(shù)說明：?
?????*?返回值：最大ID
????? */
???? public ?String?getMaxID()? {
???????? return ?productsDao.getMaxID();
????}

???? /**?*/ /**
?????*?函數(shù)說明：修改信息
?????*?參數(shù)說明：?對象
?????*?返回值：
????? */
???? public ? void ?updateProductd(Products?pd)? {
????????productsDao.updateProductd(pd);
????}

???? /**?*/ /**
?????*?函數(shù)說明：查詢信息
?????*?參數(shù)說明：?集合
?????*?返回值：
????? */
???? public ?List?queryProducts(String?fieldname,String?value)? {
???????? return ?productsDao.queryProducts(fieldname,?value);
????}
????
???? /**?*/ /**
?????*?函數(shù)說明：獲得總行數(shù)
?????*?參數(shù)說明：?
?????*?返回值：總行數(shù)
????? */
???? public ? int ?getRows(String?fieldname,String?value)? {
???????? return ?productsDao.getRows(fieldname,?value);
????}
????
???? /**?*/ /**
?????*?函數(shù)說明：查詢一段信息
?????*?參數(shù)說明：?集合
?????*?返回值：
????? */
???? public ?List?queryProducts(String?fieldname,String?value, int ?pageSize,? int ?startRow)? {
???????? return ?productsDao.queryProducts(fieldname,?value,pageSize,startRow);
????}

???? public ?ProductsDao?getProductsDao()? {
???????? return ?productsDao;
????}

???? public ? void ?setProductsDao(ProductsDao?productsDao)? {
???????? this .productsDao? = ?productsDao;
????}

}

?

基本的業(yè)務層代碼就這些了。因為還有分頁的業(yè)務，所以接下來編寫分頁的代碼。

分頁是個公共的類，所以放在 com.game.commons 中。

Pager 類，封裝了分頁需要的屬性，代碼如下：

package ?com.game.commons;

import ?java.math. * ;

public ? class ?Pager? {
???? private ? int ?totalRows;? // 總行數(shù)
???? private ? int ?pageSize? = ? 30 ;? // 每頁顯示的行數(shù)
???? private ? int ?currentPage;? // 當前頁號
???? private ? int ?totalPages;? // 總頁數(shù)
???? private ? int ?startRow;? // 當前頁在數(shù)據(jù)庫中的起始行
????
???? public ?Pager()? {
????}
????
???? public ?Pager( int ?_totalRows)? {
????????totalRows? = ?_totalRows;
????????totalPages = totalRows / pageSize;
???????? int ?mod = totalRows % pageSize;
???????? if (mod > 0 ) {
????????????totalPages ++ ;
????????}
????????currentPage? = ? 1 ;
????????startRow? = ? 0 ;
????}
????
???? public ? int ?getStartRow()? {
???????? return ?startRow;
????}
???? public ? int ?getTotalPages()? {
???????? return ?totalPages;
????}
???? public ? int ?getCurrentPage()? {
???????? return ?currentPage;
????}
???? public ? int ?getPageSize()? {
???????? return ?pageSize;
????}
???? public ? void ?setTotalRows( int ?totalRows)? {
???????? this .totalRows? = ?totalRows;
????}
???? public ? void ?setStartRow( int ?startRow)? {
???????? this .startRow? = ?startRow;
????}
???? public ? void ?setTotalPages( int ?totalPages)? {
???????? this .totalPages? = ?totalPages;
????}
???? public ? void ?setCurrentPage( int ?currentPage)? {
???????? this .currentPage? = ?currentPage;
????}
???? public ? void ?setPageSize( int ?pageSize)? {
???????? this .pageSize? = ?pageSize;
????}
???? public ? int ?getTotalRows()? {
???????? return ?totalRows;
????}
???? public ? void ?first()? {
????????currentPage? = ? 1 ;
????????startRow? = ? 0 ;
????}
???? public ? void ?previous()? {
???????? if ?(currentPage? == ? 1 )? {
???????????? return ;
????????}
????????currentPage -- ;
????????startRow? = ?(currentPage? - ? 1 )? * ?pageSize;
????}
???? public ? void ?next()? {
???????? if ?(currentPage? < ?totalPages)? {
????????????currentPage ++ ;
????????}
????????startRow? = ?(currentPage? - ? 1 )? * ?pageSize;
????}
???? public ? void ?last()? {
????????currentPage? = ?totalPages;
????????startRow? = ?(currentPage? - ? 1 )? * ?pageSize;
????}
???? public ? void ?refresh( int ?_currentPage)? {
????????currentPage? = ?_currentPage;
???????? if ?(currentPage? > ?totalPages)? {
????????????last();
????????}
????}
}

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PagerService 類，主要有個 getPager 方法返回 Pager 類。代碼如下：

package ?com.game.commons;

public ? class ?PagerService? {
???? public ?Pager?getPager(String?currentPage,String?pagerMethod, int ?totalRows)? {
???????? // ????定義pager對象，用于傳到頁面
????????Pager?pager? = ? new ?Pager(totalRows);
???????? // ????如果當前頁號為空，表示為首次查詢該頁
???????? // ????如果不為空，則刷新pager對象，輸入當前頁號等信息
???????? if ?(currentPage? != ? null )? {
????????????pager.refresh(Integer.parseInt(currentPage));
????????}
???????? // ????獲取當前執(zhí)行的方法，首頁，前一頁，后一頁，尾頁。
???????? if ?(pagerMethod? != ? null )? {
???????????? if ?(pagerMethod.equals( " first " ))? {
????????????????pager.first();
????????????} ? else ? if ?(pagerMethod.equals( " previous " ))? {
????????????????pager.previous();
????????????} ? else ? if ?(pagerMethod.equals( " next " ))? {
????????????????pager.next();
????????????} ? else ? if ?(pagerMethod.equals( " last " ))? {
????????????????pager.last();
????????????}
????????}
???????? return ?pager;
????}
}

?

?

這個分頁方法比較簡單，而且功能也齊全，許多頁面級的開源 table 中分頁很多也是基于這個原理，所以理解了這個分頁，對其他各種分頁技術的理解也就迎刃而解了。

?

服務層的代碼就這些了，接下來就可以寫 spring 的配置文件來用 spring 管理這些 Dao 和 Service 了。

在 spring-context 包中新建 applicationContext.xml 。配置的寫法如下：

<? xml?version="1.0"?encoding="ISO-8859-1" ?>
<! DOCTYPE?beans?PUBLIC?"-//SPRING//DTD?BEAN//EN"?"http://www.springframework.org/dtd/spring-beans.dtd" >
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< beans >
???? <!-- ?dataSource?config? -->
???? < bean? id ="dataSource" ?class ="org.springframework.jndi.JndiObjectFactoryBean" >
???????? < property? name ="jndiName" >
???????????? < value > java:comp/env/jdbc/game </ value >
???????? </ property >
???? </ bean >
<!-- ?SessionFactory? -->
???? < bean? id ="sessionFactory"
????????class ="org.springframework.orm.hibernate3.LocalSessionFactoryBean" >

???????? < property? name ="dataSource" >
???????????? < ref? bean ="dataSource" />
???????? </ property >
???????? < property? name ="configLocation" >
???????????? < value > classpath:com\game\bean\hibernate\hibernate.cfg.xml </ value >
???????? </ property > ????????
???? </ bean >
????
???? <!-- ?TransactionManager?? -->
???? < bean? id ="transactionManager"
????????class ="org.springframework.orm.hibernate3.HibernateTransactionManager" >
???????? < property? name ="sessionFactory" >
???????????? < ref? local ="sessionFactory" />
???????? </ property >
???? </ bean >
<!-- ?DAO? -->
???? < bean? id ="productsDao" ?class ="com.game.products.dao.hibernate.ProductsMapDao" >
???????? < property? name ="sessionFactory" >
???????????? < ref? bean ="sessionFactory" />
???????? </ property >
???? </ bean >
????
???? <!-- ?Services? -->
????? < bean? id ="productsService" ?class ="com.game.products.services.ProductsServiceImp" >
???????? < property? name ="productsDao" >
???????????? < ref? bean ="productsDao" />
???????? </ property >
???? </ bean > ?
< bean? id ="pagerService" ?class ="com.game.commons.PagerService" >
???? </ bean >
</beans>

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配置文件不難，主要是些 IOC 控制。數(shù)據(jù)庫鏈接我采用的是數(shù)據(jù)源方式，需要在 tomcat 的conf文件夾下的 server.xml 中添加數(shù)據(jù)源，添加的數(shù)據(jù)如下：

< Context? path ="/game" ?docBase ="D:\tomcat-5.5.20\webapps\game" ?debug ="0" ?reloadable ="true" >
???????? < Resource
???????????? name ="jdbc/game"
????????????type ="javax.sql.DataSource"
????????????password =""
????????????driverClassName ="net.sourceforge.jtds.jdbc.Driver"
????????????maxIdle ="2"
????????????maxWait ="5000"
????????????username ="sa"
????????????url ="jdbc:jtds:sqlserver://127.0.0.1:16899/game"
????????????maxActive ="4" />

???????? </ Context >

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這個數(shù)據(jù)源是針對 tomcat 5.5 以上版本的，以下版本的寫法有所不同，不同之處可以用 google 搜索得知。這個數(shù)據(jù)源很簡單，并沒有過多的配置來優(yōu)化系統(tǒng)，只是為了讓項目更容易讓人理解。需要注意都是，我的數(shù)據(jù)鏈接的JDBC包是jtds包，而不是普通的那個三個jar包。

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下一篇，將寫 Web 層的代碼了。

struts+spring+hibernate 的 web 應用 < 四 > Web 層代碼編寫(1)

struts+spring+hibernate 的 web 應用 < 四 > Web 層代碼編寫(2)