JDBC

1.

在Java工程下建立文件夾lib，放入mysql-connector-java-5.1.38-bin.jar，然後點擊右鍵”add to build path“。

2.

創建與數據庫對應的實體類：

package entity;

import java.io.Serializable;

public class Users implements Serializable{

	/**
	 * 
	 */
	private static final long serialVersionUID = -5350994043280204179L;
	
	private String id;
	private String address;
	private String loginName;
	private Integer loginPwd;
	private String name;
	private String phone;
	private String mail;
	public String getId() {
		return id;
	}
	public void setId(String id) {
		this.id = id;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	public String getLoginName() {
		return loginName;
	}
	public void setLoginName(String loginName) {
		this.loginName = loginName;
	}
	public Integer getLoginPwd() {
		return loginPwd;
	}
	public void setLoginPwd(Integer loginPwd) {
		this.loginPwd = loginPwd;
	}
	public String getName() {
		return name;
	}
	public void setName(String name) {
		this.name = name;
	}
	public String getPhone() {
		return phone;
	}
	public void setPhone(String phone) {
		this.phone = phone;
	}
	public String getMail() {
		return mail;
	}
	public void setMail(String mail) {
		this.mail = mail;
	}
	public Users() {
		
	}
	public Users(String id, String address, String loginName, Integer loginPwd,
			String name, String phone, String mail) {
		super();
		this.id = id;
		this.address = address;
		this.loginName = loginName;
		this.loginPwd = loginPwd;
		this.name = name;
		this.phone = phone;
		this.mail = mail;
	}
	
}

3.連接數據庫以及測試增刪改查等操作：

package util;

import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.junit.Test;

import com.mysql.jdbc.Connection;
import com.mysql.jdbc.PreparedStatement;

import entity.Users;

public class DBUtils {
	
	private static String DRIVER = "com.mysql.jdbc.Driver";
	private static String URL="jdbc:mysql://127.0.0.1:3306/grade_db?characterEncoding=utf8&useSSL=true";
	private static String USER="root";
	private static String PAWWORD="123456";
	
	static Connection conn = null ;
	static PreparedStatement stmt = null;
	static ResultSet rst = null;
	
	/**
	 * 數據庫連接
	 * @return
	 */
	private static Connection getConnection(){
		try {
			Class.forName(DRIVER);
			conn = (Connection) DriverManager.getConnection(URL, USER, PAWWORD);
		} catch (ClassNotFoundException e) {
			e.printStackTrace();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		System.out.println("get connection succeed");
		return conn;
	}
	/**
	 * 插入數據
	 * @param users
	 * @return
	 */
	private static int insert(Users users){
		Connection conn = getConnection();
		int i = 0;
		String sql = "insert into users (address,loginName,loginPwd) values(?,?,?)";
		try {
			PreparedStatement pstmt;
			pstmt = (PreparedStatement) conn.prepareStatement(sql);
			pstmt.setString(1, users.getAddress());
			pstmt.setString(2, users.getLoginName());
			pstmt.setInt(3, users.getLoginPwd());
	        i = pstmt.executeUpdate();
	        pstmt.close();
	        conn.close();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return i;
	}
	/**
	 * 更新數據
	 * @param users
	 * @return
	 */
	private static int update(Users users){
		Connection conn = getConnection();
		String sql = "update users set address='"+users.getAddress()+"'where loginPwd='"+users.getLoginPwd()+"'";
		PreparedStatement pstmt ;
		int i = 0;
		try {
			pstmt = (PreparedStatement) conn.prepareStatement(sql);
			i = pstmt.executeUpdate();
			System.out.println("resutl: " + i);
			pstmt.close();
			conn.close();
		} catch (SQLException e) {
			e.printStackTrace();
		}
		return i;
	}
	/**
	 * 查詢所有 select all
	 * @return
	 */
	private static Integer getAll(){
		Connection conn = getConnection();
	    String sql = "select * from users";
	    PreparedStatement pstmt;
	    try {
	        pstmt = (PreparedStatement)conn.prepareStatement(sql);
	        ResultSet rs = pstmt.executeQuery();
	        int col = rs.getMetaData().getColumnCount();
	        System.out.println("============================");
	        while (rs.next()) {
	            for (int i = 1; i <= col; i++) {
	                System.out.print(rs.getString(i) + "\t");
	                if ((i == 2) && (rs.getString(i).length() < 8)) {
	                    System.out.print("\t");
	                }
	             }
	            System.out.println("");
	        }
	            System.out.println("============================");
	    } catch (SQLException e) {
	        e.printStackTrace();
	    }
	    return null;
	}
	/**
	 * 刪除
	 * @param address
	 * @return
	 */
	private static int delete(String address) {
	    Connection conn = getConnection();
	    int i = 0;
	    String sql = "delete from users where address='" + address + "'";
	    PreparedStatement pstmt;
	    try {
	        pstmt = (PreparedStatement) conn.prepareStatement(sql);
	        i = pstmt.executeUpdate();
	        System.out.println("resutl: " + i);
	        pstmt.close();
	        conn.close();
	    } catch (SQLException e) {
	        e.printStackTrace();
	    }
	    return i;
	}
	/**
	 * 測試
	 */
	@Test
	public void test(){
		
		//測試數據庫連接
		//getConnection();
		
		//插入數據
		//Users users = new Users();
		//users.setAddress("guangzohu");
		//users.setLoginName("456789");
		//users.setLoginPwd(453455);
		//insert(users);
		
		//更新數據
		//Users users = new Users();
		//users.setAddress("beijing");
		//users.setLoginPwd(80);
		//update(users);
		
		//查詢所有
		getAll();
	}
}