M层：模型层
封装一条信息的所有属性JavaBean.java ，即VO package MVC;
public class JavaBean {
private int id; private String name; private String password; private String sex; private int age; public JavaBean() { }
public JavaBean(int id, String name, String password, String sex, int }
public int getId() { }
public void setId(int id) { }
public String getName() { }
public void setName(String name) { }
public String getPassword() { }
public void setPassword(String password) { }
public String getSex() {
return sex;
this.password = password; return password; this.name = name; return name; this.id = id; return id; this.id = id; this.name = name;
this.password = password; this.sex = sex; this.age = age; super();
// TODO Auto-generated constructor stub
age) {
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}
}
public void setSex(String sex) { }
public int getAge() { }
public void setAge(int age) { }
this.age = age; return age; this.sex = sex;
封装数据库连接以及操作JavaBean所用到的方法，
SqlBean.java文件即DAO
package MVC;
//封装数据库连接以及操作JavaBean所用到的方法，即DAO import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; //import java.util.List; public class SqlBean {
/**
*操作数据库的方法 */
// 定义数据库驱动程序
String DBDRIVER = \ ; // 定义数据库连接对象，属于java.sql包中的接口 Connection con=null;
//定义PreapredStatement对象，用于操作数据库 PreparedStatement pre=null; // 查询返回的结果集对象 ResultSet rs=null; public SqlBean() {
try { }
// 1、加载驱动程序
Class.forName(DBDRIVER); e.printStackTrace();
} catch (ClassNotFoundException e) {
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try {
// 2、数据库连接地址
con=DriverManager.getConnection(\ } /**
* @author help *
*插入新的一条记录 * @return */
public int getInsert(String sql,JavaBean jBean) { { } } /**
* @author help *
return count; try {
//关闭数据库
pre.close();//关闭操作 int count =0; try { } finally
pre = con.prepareStatement(sql); pre.setString(1,jBean.getName()); pre.setString(2,jBean.getPassword()); pre.setString(3,jBean.getSex()); pre.setInt(4,jBean.getAge()); count=pre.executeUpdate(); e.printStackTrace(); } catch (SQLException e) { }
e.printStackTrace();
xdstudent\,\,\);
} catch (SQLException e) {
con.close();//关闭连接 } catch (SQLException e) { }
// TODO Auto-generated catch block e.printStackTrace();
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*删除一条记录 * @return */
public int getDelete(String sql,int id) { } /**
* @author help *
*根据ID查询某一条记录 * @return */
public JavaBean getSearchById(String sql,int id) {
JavaBean jBean = new JavaBean(); try {
pre = con.prepareStatement(sql); pre.setInt(1, id); rs=pre.executeQuery(); while(rs.next()) int count =0; try { } finally { }
return count;
try { }
pre.close(); con.close();
// TODO Auto-generated catch block e.printStackTrace();
pre = con.prepareStatement(sql); pre.setInt(1, id);
count=pre.executeUpdate(); e.printStackTrace();
} catch (SQLException e) {
} catch (SQLException e) {
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}
{ }
{ }
jBean.setId(rs.getInt(\));
jBean.setName(rs.getString(\));
jBean.setPassword(rs.getString(\)); jBean.setSex(rs.getString(\)); jBean.setAge(rs.getInt(\));
} catch (SQLException e)
e.printStackTrace();
return jBean;
/**
* @author help *
*更新某一条记录 * @return */
public int getUpdate(String sql,JavaBean jBean) {
int count =0; try { } finally { }
try { }
pre.close(); con.close();
// TODO Auto-generated catch block e.printStackTrace();
pre = con.prepareStatement(sql); pre.setInt(5,jBean.getId()); pre.setString(1,jBean.getName()); pre.setString(2,jBean.getPassword()); pre.setString(3,jBean.getSex()); pre.setInt(4,jBean.getAge()); count = pre.executeUpdate(); // TODO Auto-generated catch block e.printStackTrace();
} catch (SQLException e) {
} catch (SQLException e) {
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