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  • Java原生操作数据库(不使用框架)

    1.引入数据库驱动的jar包 以通过maven引入mysql driver为例

      1.1 到http://mvnrepository.com 搜索 mysql

    1.2 复制所需maven配置文件到工程的 pom.xml

    <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>6.0.6</version>
    </dependency>

    2.创建数据库连接类DBUtil.java用以连接与关闭数据库

    //文件名:DBUtil.java
    
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.sql.Statement;
    
    public class DBUtil {
    
        static String user = "root";
        static String password = "root";
        static String url = "jdbc:mysql://localhost【数据库地址】:3306【端口】/【数据库名称】?serverTimezone=UTC";
    
        static {
            try {
                Class.forName("com.mysql.cj.jdbc.Driver");
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }
        }
    
        public static Connection getConnection() {
            Connection conn = null;
            try {
                conn = DriverManager.getConnection(url, user, password);
            } catch (SQLException e) {
                e.printStackTrace();
            }
            return conn;
        }
    
        public static void closeJDBC(ResultSet rs, Statement stmt, Connection conn) {
            if (rs != null) {
                try {
                    rs.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
            if (stmt != null) {
                try {
                    stmt.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
            if (conn != null) {
                try {
                    conn.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
        }
    }

    3.在java代码中对表进行操作

    3.1 查,删,改类似

    //查找table表重的 id和name
    String sql = "select id,name from table";
    Connection conn = DBUtil.getConnection();
    PreparedStatement pstmt = null;
    try {
          conn.setAutoCommit(false);
          pstmt = conn.prepareStatement(sql);
           ResultSet rs = pstmt.executeQuery();
           json = ResultSetToJson.ResultSetToJsonArray(rs);
         }catch (SQLException e){
         try {
               conn.rollback();
         }catch (SQLException e1){
               e1.printStackTrace();
         }
    }finally {
        DBUtil.closeJDBC(null, pstmt, conn);
    }
         return json;

    3.1 增

    int basicinfoID = 0;
    String sql = "INSERT INTO tb_resume_basicinfo("
        + "basicinfo_id, realname, gender, birthday, current_loc, "
        + "resident_loc, telephone, email, job_intension, job_experience, head_shot,applicant_id) "
        +"VALUES(SEQ_ITOFFER_RESUMEBASICINFO.NEXTVAL,?,?,?,?,?,?,?,?,?,?,?)";
    Connection conn = DBUtil.getConnection();
    PreparedStatement pstmt = null;
            try {
                // 关闭自动提交
                conn.setAutoCommit(false);
                pstmt = conn.prepareStatement(sql);
                pstmt.setString(1, basicinfo.getRealName());
                pstmt.setString(2, basicinfo.getGender());
                pstmt.setTimestamp(3, basicinfo.getBirthday() == null ? null
                        : new Timestamp(basicinfo.getBirthday().getTime()));
                pstmt.setString(4, basicinfo.getCurrentLoc());
                pstmt.setString(5, basicinfo.getResidentLoc());
                pstmt.setString(6, basicinfo.getTelephone());
                pstmt.setString(7, basicinfo.getEmail());
                pstmt.setString(8, basicinfo.getJobIntension());
                pstmt.setString(9, basicinfo.getJobExperience());
                pstmt.setString(10, basicinfo.getHeadShot());
                pstmt.setInt(11, applicantID);
                pstmt.executeUpdate();
    } catch (SQLException e) {
                try {
                    // 事务回滚
                    conn.rollback();
                } catch (SQLException e1) {
                    e1.printStackTrace();
                }
                e.printStackTrace();
            } finally {
                DBUtil.closeJDBC(null, pstmt, conn);
            }
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  • 原文地址:https://www.cnblogs.com/zhouheblog/p/11044375.html
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