jdbc封装代码

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mob604756e92c53 2019-01-04 18:08:00

文章标签 jdbc封装代码 sql java i++ mysql 文章分类 代码人生

jdbc封装代码


package jdbcUtil;

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;

import jdbc.RowMap;

public class JdbcUtil {
  public static Connection getConnection(){
    Connection connection=null;
    //加载驱动
    try {
      Class.forName("com.mysql.jdbc.Driver");
      //2创建连接（主机名，端口号，用户名，密码）
      connection= DriverManager.getConnection("jdbc:mysql://localhost:3306/student", "root", "123456");
    }
     catch (ClassNotFoundException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
     return connection;
  
  }

  public static void close(Connection connection){
    try {
      if(connection!=null){
        connection.close();
      }
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
  }

  public static int executeUpdate(String sql,Object... params){
    int result=0;
    Connection connection=getConnection();
    PreparedStatement pstmt;
    try {
      pstmt = connection.prepareStatement(sql);
      if(params!=null){
        for(int i=0;i<params.length;i++){
          pstmt.setObject(i+1, params[i]);
        }
      result=pstmt.executeUpdate();
      }
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }finally {
      close(connection);
    }
    return result;
  } 
  
  
  public static <T>List<T> executeSelect(String sql,RowMap<T> rowMap,Object...params){
    List<T> result=new ArrayList<>();
    Connection connection=getConnection();
    try {
      PreparedStatement pstmt=connection.prepareStatement(sql);
      if(params!=null){
        for(int i=0;i<params.length;i++){
          pstmt.setObject(i+1, params[i]);
        }
      }
      ResultSet rs=pstmt.executeQuery();
      while(rs.next()){
        //将数据行 映射到对象中
        T t=rowMap.rowMapping(rs);
        result.add(t);
      }
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }finally {
      close(connection);
    }
    return result;
  } 

}

JdbcUtil.java


package jdbcUtil;

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;

import jdbc.RowMap;

public class JdbcUtil {
  public static Connection getConnection(){
    Connection connection=null;
    //加载驱动
    try {
      Class.forName("com.mysql.jdbc.Driver");
      //2创建连接（主机名，端口号，用户名，密码）
      connection= DriverManager.getConnection("jdbc:mysql://localhost:3306/student", "root", "123456");
    }
     catch (ClassNotFoundException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
     return connection;
  
  }

  public static void close(Connection connection){
    try {
      if(connection!=null){
        connection.close();
      }
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }
  }

  public static int executeUpdate(String sql,Object... params){
    int result=0;
    Connection connection=getConnection();
    PreparedStatement pstmt;
    try {
      pstmt = connection.prepareStatement(sql);
      if(params!=null){
        for(int i=0;i<params.length;i++){
          pstmt.setObject(i+1, params[i]);
        }
      result=pstmt.executeUpdate();
      }
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }finally {
      close(connection);
    }
    return result;
  } 
  
  
  public static <T>List<T> executeSelect(String sql,RowMap<T> rowMap,Object...params){
    List<T> result=new ArrayList<>();
    Connection connection=getConnection();
    try {
      PreparedStatement pstmt=connection.prepareStatement(sql);
      if(params!=null){
        for(int i=0;i<params.length;i++){
          pstmt.setObject(i+1, params[i]);
        }
      }
      ResultSet rs=pstmt.executeQuery();
      while(rs.next()){
        //将数据行 映射到对象中
        T t=rowMap.rowMapping(rs);
        result.add(t);
      }
    } catch (SQLException e) {
      // TODO Auto-generated catch block
      e.printStackTrace();
    }finally {
      close(connection);
    }
    return result;
  }
  
    

}

jdbcBean.java


package jdbc;

import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.HashMap;
import java.util.List;
import java.util.Scanner;import jdbcUtil.JdbcUtil;class jdbcBean {
  public static void main(String[] args) {
    List<Student> list=select();
    System.out.println(list);
    /*jdbcBean jdbcBean=new jdbcBean();
    jdbcBean.tset();*/
    /*delete();*/
    /*add();*/
  }
  
  public static int delete(){ 
    return JdbcUtil.executeUpdate("delete from student where sid=? and sname=?", 10,"¹þÊ¿Ææ");
    
  }
  
  public static int update(){ 
    return JdbcUtil.executeUpdate("update student set sname=?,age=?,sex=? where sid=?","mojie",2,"ÐÛ",1);
    
  }
  
  public static int add(){
    return JdbcUtil.executeUpdate("insert into student(sname,age,sex) values(?,?,?)", "ÍÛ¹þ",3,"ÐÛ");
    
  }
   public static List select(){
     
     return jdbcUtil.JdbcUtil.executeSelect("select * from student",new RowMap<Student>(){
       @Override
       public Student rowMapping(ResultSet rs){
         Student student=new Student(); 
        try {
          student.setAge(rs.getInt("age"));
          student.setName(rs.getString("sname"));
          student.setSex(rs.getString("sex"));
          student.setSid(rs.getInt("sid"));
        } catch (SQLException e) {
          // TODO Auto-generated catch block
          e.printStackTrace();
        }
         return student;
       }
     }, null);
      /*Connection connection=JdbcUtil.getConnection();
      List<Student> list=new ArrayList<>();
      try {
        PreparedStatement pstmt=connection.prepareStatement("select * from student");
        ResultSet rs= pstmt.executeQuery();
        while (rs.next()) {
          Student student=new Student();  
          student.setAge(rs.getInt("age"));
          student.setName(rs.getString("sname"));
          student.setSex(rs.getString("sex"));
          student.setSid(rs.getInt("sid"));
          list.add(student);
          
        }
      } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }finally {
        JdbcUtil.close(connection);
      }
      return list;*/
  }
   public void tset(){
     HashMap<String,Student> sHashMap=new HashMap<>();
     for(int i=0;i<4;i++){
       System.out.println("qingshuru");
       Scanner scanner=new Scanner(System.in);
       Integer sid=scanner.nextInt();
       String sname=scanner.next();
       Integer age=scanner.nextInt();
       String sex=scanner.next();
       Student student=new Student(sname, age, sid, sex);
       sHashMap.put("Student"+i, student);
     }
     for(int i=0;i<4;i++){
       System.out.println(sHashMap.get("Student"+i));
     }
       
    
   }
}

RowMap.java


package jdbc;

import java.sql.ResultSet;

public interface RowMap<T> {
  public T rowMapping(ResultSet rs);
}

Student.java


package jdbc;

public class Student {
  private String name;
  private int age;
  private int sid;
  private String sex;
  public String getName() {
    return name;
  }
  public Student(String name, int age, int sid, String sex) {
    super();
    this.name = name;
    this.age = age;
    this.sid = sid;
    this.sex = sex;
  }
  public int getSid() {
    return sid;
  }
  public void setSid(int sid) {
    this.sid = sid;
  }
  public void setName(String name) {
    this.name = name;
  }
  public int getAge() {
    return age;
  }
  public void setAge(int age) {
    this.age = age;
  }
  public String getSex() {
    return sex;
  }
  public void setSex(String sex) {
    this.sex = sex;
  }
  @Override
  public String toString() {
    return "Student [name=" + name + ", age=" + age + ", sex=" + sex + "]";
  }
  public Student(String name, int age, String sex) {
    super();
    this.name = name;
    this.age = age;
    this.sex = sex;
  }
  public Student() {
    super();
    // TODO Auto-generated constructor stub
  }
  
  
}