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  • 大小: 6KB
    文件類型: .java
    金幣: 1
    下載: 0 次
    發布日期: 2021-05-28
  • 語言: Java
  • 標簽: java??mysql??

資源簡介

寫好sql語句,調用該工具類內的方法,即可實現增刪改查mysql數據庫的操作。帶有詳細解釋

資源截圖

代碼片段和文件信息

package?db;

/*
?*?To?change?this?license?header?choose?License?Headers?in?Project?Properties.
?*?To?change?this?template?file?choose?Tools?|?Templates
?*?and?open?the?template?in?the?editor.
?*/

import?com.sun.rowset.CachedRowSetImpl;
import?java.sql.*;
import?javax.sql.rowset.CachedRowSet;

/**
?*
?*?@author?Administrator
?*/
public?class?DBUtil?{
static?String?_url?=?“jdbc:mysql://localhost:3306/test“;
static?String?_username?=?“root“;
static?String?_password?=?“root“;
????//按傳入的SQL進行數據庫查詢操作
????@SuppressWarnings(“finally“)
public?static?CachedRowSet?querySQL(String?sql)?throws?SQLException?{
????????//離線集合
????????CachedRowSet?crs?=?new?CachedRowSetImpl();
????????//定義數據庫連接對象·Connection.???定義傳輸對象.???定義結果集對象
????????Connection?conn?=?null;
????????Statement?stmt?=?null;
????????ResultSet?rs?=?null;
????????try?{
????????????//加載Driver驅動
????????????Class.forName(“com.mysql.jdbc.Driver“);
????????????//創建數據庫連接對象connection??localhost:3306分別為本機ip和數據庫接入端口號
????????????conn?=?DriverManager.getConnection(_url?_username?_password);
????????????//創建一個可向數據庫發送SQL命令并返回結果的傳送對象
????????????stmt?=?conn.createStatement();
????????????//將sql命令通過sql傳送對象傳送到數據庫執行
????????????rs?=?stmt.executeQuery(sql);
????????????//處理結果集
????????????crs.populate(rs);
????????}?catch?(Exception?ex)?{
????????????ex.printStackTrace();
????????}?finally?{
????????????//手動關閉資源
????????????if?(rs?!=?null)?{
????????????????try?{
????????????????????rs.close();
????????????????}?catch?(Exception?ex)?{
????????????????????ex.printStackTrace();
????????????????}
????????????}
????????????if?(stmt?!=?null)?{
????????????????try?{
????????????????????stmt.close();
????????????????}?catch?(Exception?ex)?{
????????????????????ex.printStackTrace();
????????????????}
????????????}
????????????if?(conn?!=?null)?{
????????????????try?{
????????????????????conn.close();
????????????????}?catch?(Exception?ex)?{
????????????????????ex.printStackTrace();
????????????????}
????????????}
????????????return?crs;
????????}
????}

????//按傳入的SQL進行數據庫更新操作(單條、無事務)
????@SuppressWarnings(“finally“)
public?static?boolean??updateSQL(String?sql)?{
????????boolean?rtn?=?false;
????????//定義數據庫連接對象·Connection定義傳輸對象
????????Connection?conn?=?null;
????????Statement?stmt?=?null;
????????try?{
????????????//加載Driver驅動
????????????Class.forName(“com.mysql.jdbc.Driver“);
????????????//創建數據庫連接對象connection
????????????conn?=?Driver

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