java操作資料庫

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/** *  */package com.xx.db;/** * @author 
 * 實現資料庫連接 * 實現資料的查詢和更新（增刪改） * 只使用一個資料庫寫死在本檔案中即可;若使用多個資料庫，可使用設定檔實現 */import java.sql.Connection;import java.sql.DriverManager;import java.sql.ResultSet;import java.sql.SQLException;import java.sql.Statement;import java.util.ArrayList;import java.util.List;//import org.apache.commons.lang.StringUtils;//import org.testng.annotations.Test;public class DBUtils {//驅動程式名public String DBDriver = "com.mysql.jdbc.Driver";//URL指向要訪問的資料庫名public String url = "jdbc:mysql://192.168.xx.xx:3306/DataBase";public String user = "username";public String password = "password"; /* * MySQL配置時的使用者名稱user *  Java串連MySQL配置時的密碼password */public Connection connect(){try {// 載入驅動程式Class.forName(DBDriver);// 串連資料庫Connection conn = DriverManager.getConnection(url, user, password);//if(!conn.isClosed()){　　　　　　　　　　　　　　//每次都列印，太煩了，所以注釋掉了//System.out.println("Succeeded connecting to the Database!");//}return conn;}catch(ClassNotFoundException e) {   System.err.println("Sorry,can‘t find the Driver!");   e.printStackTrace(); return null;} catch(SQLException e) {   e.printStackTrace(); return null;} catch(Exception e) {   e.printStackTrace(); return null;}}/* * 擷取查詢結果ResultSet */public ResultSet selectResult(String sql) throws SQLException{// statement用來執行SQL語句Statement statement = connect().createStatement();// 要執行的SQL語句ResultSet rs = statement.executeQuery(sql);  return rs;}/* * 按列擷取查詢結果 */public List<String> getStringList(String sql, String key) throws SQLException{List<String> value = new ArrayList<String>();ResultSet rs = selectResult(sql);while(rs.next()) {  //選擇key這列資料value.add(rs.getString(key));}  rs.close(); connect().close();return value;}　　　　　　　　　　//擷取SQL執行結果的條數               public int getCount(String sql, String primaryKey) throws SQLException{int count = 0;count = getStringList(sql,primaryKey).size();return count;}　　　　　　　　　　//更新資料庫，適用於insert, update, deletepublic boolean updateResult(String sql) throws SQLException{// statement用來執行SQL語句Statement statement = connect().createStatement();int rs = 0;// 要執行的SQL語句,為防止全表更新，要判斷SQL語句中是否有WHERE子句,insert語句不必有WHERE子句if(sql.contains("update ") || sql.contains("delete ") ){if(sql.contains(" WHERE ") || sql.contains(" where ") ){rs = statement.executeUpdate(sql);}}else if(sql.contains("insert into ")){rs = statement.executeUpdate(sql);}statement.close();connect().close();if(rs==1){return true;}else return false;}//@Test//public void test() throws SQLException{//String sql = "SELECT * FROM tableName WHERE c_username=‘user‘";//List<String> value =getStringList(sql,"username");//System.out.println(value.toString());//System.out.println(getCount(sql,"c_uid"));////String sql2 = "update shop_tableName set a=‘1101‘ WHERE username=‘user‘";//String sql3 = "insert into tableName (id,name) values (9999999,‘11‘)";//String sql4 = "delete from tableName WHERE name=‘11‘";////System.out.println(updateResult(sql3));////System.out.println(sql4.contains(" WHERE "));//} }

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java操作資料庫