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锁定老帖子 主题：jdbc还是ibatis？
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发表时间：2007-02-26
我以前做的一个对jdbc的封装(仿照Spring的实现,当然功能弱些,所以代码少很多,容易看)
以下是对jdbc进行了简单的封装:使用Template mothod模式和回调接口大大减少了对jdbc的低级操作。其中JdbcTemplate类提供了使用jdbc访问数据库的模板，提供了queryForObject和queryForList方法来分别获取查询到的对象和对象的聚集，execute方法来更新、插入、删除操作。提供了RowCallBackHandler接口，可以通过实现该接口来提供对查询一行的回调处理，使用PreparedStatementCallBack回调接口，来提供对PreparedStatement参数的设置，提供了ORMaping接口，通过实现该接口可以很容易实现关系数据库与domain对象的映射，并产生可重用的逻辑 以下是代码包含对JDBC的封装和Dao的实现:
package edu.jlu.fuliang.library.jdbc;
import java.util.ArrayList;
import java.util.List;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
public class JdbcTemplate {
public List query(String sql,RowCallBackHandler handler){
Connection connection = JdbcUtils.createConnection();
PreparedStatement ps = JdbcUtils.createPreparedStatement(sql,connection);
ResultSet rs = null;
List list = new ArrayList();
try {
rs = ps.executeQuery();
while(rs.next()){
list.add(handler.processRow(rs));
}
} catch (SQLException e) {
e.printStackTrace();
}finally{
JdbcUtils.closeStatement(ps);
JdbcUtils.relaseConnection(connection);
}
return list;
}
public Object queryForObject(String sql,RowCallBackHandler handler){
Connection connection = JdbcUtils.createConnection();
PreparedStatement ps = JdbcUtils.createPreparedStatement(sql,connection);
ResultSet rs = null;
Object o = null;
try {
rs = ps.executeQuery();
rs.next();
o = handler.processRow(rs);
} catch (SQLException e) {
e.printStackTrace();
}finally{
JdbcUtils.closeStatement(ps);
JdbcUtils.relaseConnection(connection);
}
return o;
}
public void executeUpdate(String sql,PreparedStatementCallBack pareparedStatementCallBack){
Connection connection = JdbcUtils.createConnection();
PreparedStatement ps = JdbcUtils.createPreparedStatement(sql,connection);
try {
pareparedStatementCallBack.doInStatement(ps);
ps.executeUpdate();
} catch (SQLException e) {
e.printStackTrace();
}finally{
JdbcUtils.closeStatement(ps);
JdbcUtils.relaseConnection(connection);
}
}
}
//回调接口RowCallBackHandler
package edu.jlu.fuliang.library.jdbc;
import java.sql.ResultSet;
public interface RowCallBackHandler {
public Object processRow(ResultSet rs);
}
///回调接口PreparedStatementCallBack
package edu.jlu.fuliang.library.jdbc;
import java.sql.PreparedStatement;
import java.sql.SQLException;
public interface PreparedStatementCallBack {
public void doInStatement(PreparedStatement stmt)throws SQLException;
}
//ORMaping接口
package edu.jlu.fuliang.library.jdbc;
import java.sql.ResultSet;
public interface ORMaping {
public Object mapping(ResultSet rs,Object o);
}
//JdbcUtils.java
package edu.jlu.fuliang.library.jdbc;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;
public class JdbcUtils {
public static Connection createConnection(){//为了简单，进行了硬编码
String user = "root";
String passwd = "123456";
String url = "jdbc:mysql://localhost/test?useUnicode=true&characterEncoding=gb2312";
Connection connection = null;
try{
Class.forName("com.mysql.jdbc.Driver").newInstance();
connection = DriverManager.getConnection(url,user,passwd);
}
catch(Exception e){
e.printStackTrace();
}
return connection;
}
public static PreparedStatement createPreparedStatement(String sql,Connection connection){
PreparedStatement stmt = null;
try{
stmt = connection.prepareStatement(sql);
}catch(Exception e){
e.printStackTrace();
}
return stmt;
}
public static void closeStatement(Statement s){
try {
s.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
public static void relaseConnection(Connection connection){
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
//以下是数据访问对象：
//BorrowerDao.java
package edu.jlu.fuliang.library.dao;
import edu.jlu.fuliang.library.domain.Borrower;
public interface BorrowerDao {
public Borrower queryByLastName(String lastName);
public void updateBorrower(Borrower borrower);
public void insertBorrower(Borrower borrower);
public void deleteBorrowerByLastName(String lastName);
}
// BookDao.java
package edu.jlu.fuliang.library.dao;
import java.util.List;
import edu.jlu.fuliang.library.domain.Book;
public interface BookDao {
public Book queryByTitle(String title);
public List queryByAuthor(String author);
public List queryByBorrowerLastName(String firstName);
public void updateBook(Book book);
public void insertBook(Book book);
public void deleteBookByTile(String title);
}
// BorrowOrReturnDao.java
package edu.jlu.fuliang.library.dao;
public interface BorrowOrReturnDao {
public void borrowBook(String borrowerLastName,String bookTile);
public void returnBook(String borrowerLastName,String bookTile);
}
//抽象工厂：
package edu.jlu.fuliang.library.dao;
public interface DaoFactory {
public BookDao createBookDao();
public BorrowerDao createBorrowerDao();
public BorrowOrReturnDao createBorrowOrReturnDao();
}
//具体工厂：
package edu.jlu.fuliang.library.dao;
import edu.jlu.fuliang.library.dao.mysql.BookDaoImpl;
import edu.jlu.fuliang.library.dao.mysql.BorrowerDaoImpl;
public class MysqlDaoFactory implements DaoFactory{
public BookDao createBookDao() {
return new BookDaoImpl();
}
public BorrowerDao createBorrowerDao() {
return new BorrowerDaoImpl();
}
public BorrowOrReturnDao createBorrowOrReturnDao() {
return new BorrowOrReturnDaoImpl();
}
}
//BookDao的具体实现：
//BookDaoImpl.java
package edu.jlu.fuliang.library.dao.mysql;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
import edu.jlu.fuliang.library.dao.BookDao;
import edu.jlu.fuliang.library.domain.Book;
import edu.jlu.fuliang.library.jdbc.*;
public class BookDaoImpl implements BookDao{
private JdbcTemplate jdbcTemplate = new JdbcTemplate();
public Book queryByTitle(String title) {
String sql = "select * from book where title = "+title;
return (Book)jdbcTemplate.queryForObject(sql,new RowCallBackHandler(){
public Object processRow(ResultSet rs) {
BookMaping map = new BookMaping();
Book book = (Book)map.mapping(rs,new Book());
return book;
}
});
}
public List queryByAuthor(String author) {
String sql = "select * from book where author = "+author;
return jdbcTemplate.query(sql,new RowCallBackHandler(){
public Object processRow(ResultSet rs) {
BookMaping map = new BookMaping();
Book book = (Book)map.mapping(rs,new Book());
return book;
}
});
}
//Borrower的具体实现：
//BookDaoImpl.java
package edu.jlu.fuliang.library.dao.mysql;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import edu.jlu.fuliang.library.dao.BorrowerDao;
import edu.jlu.fuliang.library.domain.Borrower;
import edu.jlu.fuliang.library.jdbc.JdbcTemplate;
import edu.jlu.fuliang.library.jdbc.PreparedStatementCallBack;
import edu.jlu.fuliang.library.jdbc.RowCallBackHandler;
public class BorrowerDaoImpl implements BorrowerDao{
private JdbcTemplate jdbcTemplate = new JdbcTemplate();
public Borrower queryByLastName(String lastName) {
String sql = "select * from borrower where lastName = " + lastName;
return (Borrower)jdbcTemplate.queryForObject(sql,new RowCallBackHandler(){
public Object processRow(ResultSet rs) {
BorrowerMaping borrowerMaping = new BorrowerMaping();
return borrowerMaping.mapping(rs,new Borrower());
}
});
}
public void updateBorrower(final Borrower borrower) {
String sql = "update borrower set lastname = ?,firstname=?" +
",address =?,city =?,zip=?,state=? where lastname = ?";
jdbcTemplate.executeUpdate(sql,new PreparedStatementCallBack(){
public void doInStatement(PreparedStatement stmt) throws SQLException {
stmt.setString(1,borrower.getLastName());
stmt.setString(2,borrower.getFirstName());
stmt.setString(3,borrower.getAddress());
stmt.setString(4,borrower.getCity());
stmt.setString(5,borrower.getZip());
stmt.setString(6,borrower.getState());
stmt.setString(7,borrower.getLastName());
}
});
}
public void insertBorrower(final Borrower borrower) {
String sql = "insert into borrower values(?,?,?,?,?,?)";
jdbcTemplate.executeUpdate(sql,new PreparedStatementCallBack(){
public void doInStatement(PreparedStatement stmt) throws SQLException {
stmt.setString(1,borrower.getLastName());
stmt.setString(2,borrower.getFirstName());
stmt.setString(3,borrower.getAddress());
stmt.setString(4,borrower.getCity());
stmt.setString(5,borrower.getZip());
stmt.setString(6,borrower.getState());
}
});
}
public void deleteBorrowerByLastName(final String lastName) {
String sql = "delete from borrower where lastName = ?";
jdbcTemplate.executeUpdate(sql,new PreparedStatementCallBack(){
public void doInStatement(PreparedStatement stmt) throws SQLException {
stmt.setString(1,lastName);
}
});
}
}
// BorrowOrReturnDaoImpl.java
package edu.jlu.fuliang.library.dao.mysql;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import edu.jlu.fuliang.library.dao.BorrowOrReturnDao;
import edu.jlu.fuliang.library.jdbc.JdbcTemplate;
import edu.jlu.fuliang.library.jdbc.PreparedStatementCallBack;
public class BorrowOrReturnDaoImpl implements BorrowOrReturnDao{
private JdbcTemplate jdbcTemplate = new JdbcTemplate();
public void borrowBook(final String borrowerLastName, final String bookTitle) {
String sql = "insert into book_borrower values(?,?)";
jdbcTemplate.executeUpdate(sql,new PreparedStatementCallBack(){
public void doInStatement(PreparedStatement stmt) {
try{
stmt.setString(1,borrowerLastName);
stmt.setString(2,bookTitle);
}catch(SQLException e){
e.printStackTrace();
}
}
});
}
public void returnBook(final String borrowerLastName, final String bookTitle) {
String sql = "delete from book_borrower where lastname = ?,title = ?";
jdbcTemplate.executeUpdate(sql,new PreparedStatementCallBack(){
public void doInStatement(PreparedStatement stmt) {
try{
stmt.setString(1,borrowerLastName);
stmt.setString(2,bookTitle);
}catch(SQLException e){
e.printStackTrace();
}
}
});
}
}
//book的ORMaping的实现：
// BookMaping.java
package edu.jlu.fuliang.library.dao.mysql;
import java.sql.ResultSet;
import java.sql.SQLException;
import edu.jlu.fuliang.library.domain.Book;
import edu.jlu.fuliang.library.jdbc.ORMaping;
public class BookMaping implements ORMaping{
public Object mapping(ResultSet rs, Object o) {
Book book = (Book)o;
try {
book.setTitleName(rs.getString("titleName"));
book.setAuthor(rs.getString("author"));
book.setISBN(rs.getString("isbn"));
book.setType(rs.getInt("type"));
book.setItemsAvailable(rs.getInt("itemAvailable"));
} catch (SQLException e) {
e.printStackTrace();
}
return book;
}
}
////borrower的ORMaping的实现：
// BorrowerMaping.java
package edu.jlu.fuliang.library.dao.mysql;
import java.sql.ResultSet;
import java.sql.SQLException;
import edu.jlu.fuliang.library.domain.Borrower;
import edu.jlu.fuliang.library.jdbc.ORMaping;
public class BorrowerMaping implements ORMaping{
public Object mapping(ResultSet rs, Object o) {
Borrower borrower = (Borrower)o;
try {
borrower.setLastName(rs.getString(1));
borrower.setFirstName(rs.getString(2));
borrower.setAddress(rs.getString(3));
borrower.setCity(rs.getString(4));
borrower.setZip(rs.getString(5));
borrower.setState(rs.getString(6));
} catch (SQLException e) {
e.printStackTrace();
}
return borrower;
}
}
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发表时间：2007-02-26
intolong 写道 ajoo不是写过jdbc template么？
http://www.iteye.com/topic/7068 和你同事那个差不多吧，一个继承，一个组合 他这个还不如我的那个。他的这个实现没有处理Error的情况。在Error出现的情况，不会回滚事务。 不管我的还是同事的这个都有若干个问题： 1。不支持cache。还要自己写cache，不如ibatis直接提供的cache支持方便。 2。不支持一个connection多个query或者命令。 |
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发表时间：2007-02-26
jdbc 不是架构
ibatis是架构 要用什么就看哪个架构省力 如果要升级那就要看是否非要升级所有的文件 原有的有必要修改的代码也可以用重构的方式完成 由于jdbc可以离开架构而存在 所以没必要非把所有的代码都移到新的架构上面 |
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发表时间：2007-04-13
这根本就不是技术问题，都是人的问题，人家固执保守，不肯学习新东西，确实就很无奈。当architect没有他人的拥护看来也是不行的。
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发表时间：2007-08-15
屁股决定脑袋。
因为自己的立场和利益，每个人都会坚持一些从别人看来不可理解的东西，都会时不时的担心一下这个新的外来者是不是会损害自己的利益。 最让你感觉到无能为力的是“我不care”，但这其实也是你最大的攻击点，问问他care什么？告诉他什么能帮助他更好的care这些东西。当然，一定不能忘了工程的投入产出这个最大的砝码。 |
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发表时间：2007-08-15
ibatis麻烦？你用hibernate试试
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发表时间：2007-08-16
原来的系统跑得好好的，需要很强的理由才能说服当官的决定替换。
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