jdbc封装代码

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
	}

}