PreparedStatement要点

PreparedStatement //预定义的语句


import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;


import com.maker.util.DBUtil;


public class PreparedStatement {
public static void main(String[] args) {
//插入
// student s = new student();
// s.setId("001");
// s.setName("tom");
// s.setGender("女");
// getPreparedstatement(s);

//更新
// student s = new student();
// s.setId("2");
// s.setName("小明2");
// s.setGender("男");
// getPreparedstatement(s);

//删除
// getPreparedstatement("2");

//查找
getPreparedstatement("女");

}
static void getPreparedstatement(String gen){
DBUtil util = new DBUtil();
Connection conn = util.openConnection();
// String sql = "select id , name,gender from student where id = ?";

// String sql = "insert into t_student (id,name,gender) values (?,?,?)";

// String sql = "update t_student set name = ?,gender= ? where id= ? ";

// String sql = "delete from t_student where id = ?";

String sql = "select id,name from t_student where gender=?";
try {
java.sql.PreparedStatement pstat =conn.prepareStatement(sql);
// pstat.setLong(1, 3);
// System.out.println(pstat);

// 插入
// pstat.setString(1, s.getId());
// pstat.setString(2, s.getName());
// pstat.setString(3, s.getGender());
// pstat.executeUpdate();

//更新
// pstat.setString(1, s.getName());
// pstat.setString(2, s.getGender());
// pstat.setString(3, s.getId());
// pstat.executeUpdate();

//删除
// pstat.setString(1, id);
// pstat.executeUpdate();

//查询
pstat.setString(1, gen);
ResultSet rs = pstat.executeQuery();
while(rs.next()){
String id = rs.getString("id");
String name = rs.getString(2);
System.out.println(id+"  "+ name);
}


} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}


class student{
String id;
String name;
String gender;
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getGender() {
return gender;
}
public void setGender(String gender) {
this.gender = gender;
}

}