package?com.sqq.dao;

import?com.sun.org.apache.xpath.internal.operations.Bool;

import?java.io.IOException;
import?java.io.InputStream;
import?java.sql.*;
import?java.util.Properties;

//操作數據庫的公共類
public?class?baseDao?{
????private?static?String?driver;
????private?static?String?url;
????private?static?String?username;
????private?static?String?password;

????//靜態代碼塊，類加載的時候就初始化了
????static?{
????????Properties?properties?=?new?Properties（）;
????????//通過類加載器讀取對應的資源
????????InputStream?is?=?baseDao.class.getClassLoader（）.getResourceAsStream（“db.properties“）;

????????try?{
????????????properties.load（is）;
????????}?catch?（IOException?e）?{
????????????e.printStackTrace（）;
????????}

????????driver?=?properties.getProperty（“driver“）;
????????url?=?properties.getProperty（“url“）;
????????username?=?properties.getProperty（“username“）;
????????password?=?properties.getProperty（“password“）;

????}

????//獲取數據庫的連接
????public?static?Connection?getConnection（）{
????????Connection?connection?=?null;
????????try?{
????????????Class.forName（driver）;
????????????connection=?DriverManager.getConnection（urlusernamepassword）;
????????}?catch?（Exception?e）?{
????????????e.printStackTrace（）;
????????}
????????return?connection;
????}

????//編寫查詢公共類
????public?static?ResultSet?execute（Connection?connection?PreparedStatement?preparedStatement???ResultSet?resultSet?String?sql?object[]?params）?throws?SQLException?{
????????//預編譯的sql，在后面直接執行就可以了
????????preparedStatement?=?connection.prepareStatement（sql）;
????????for?（int?i?=?0;?i?????????????//setobject占位符從1開始，但是我們的數組是從0開始
????????????preparedStatement.setobject（i+1params[i]）;
????????}
????????resultSet=preparedStatement.executeQuery（）;
????????return??resultSet;
????}

????//編寫增刪改公共類
????public?static?int?execute（Connection?connectionPreparedStatement?preparedStatement?String?sql?object[]?params）?throws?SQLException?{
????????preparedStatement?=?connection.prepareStatement（sql）;
????????for?（int?i?=?0;?i?????????????//setobject占位符從1開始，但是我們的數組是從0開始
????????????preparedStatement.setobject（i+1params[i]）;
????????}
????????int?updateRows=preparedStatement.executeUpdate（）;
????????return??updateRows;
????}

????//釋放資源
????public?static?boolean?closeResource（Connection?connectionPreparedStatement?preparedStatementResultSet?resultSet）{
????????Boolean?flag?=?true;

????????if（connection!=null）{
????????????try?{
????????????????connection.close（）;
????????????????//GC回收
????????????????connection=null;
????????????}?catch?（SQLException?e）?{
????????????????e.printStackTrace（）;
????????????????flag=false;
????????????}
????????}

????????if（preparedStatement!=null）{
????????????try?{
????????????????preparedStatement.close（）;
????????????????//GC回收
????????????????preparedStatement=null;
????????????}?catch?（SQLException?e）?{
????????????????e.printStackTrace（）;
??????????

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????目錄???????????0??2020-05-11?11:00??smbms\
?????目錄???????????0??2020-05-11?11:02??smbms\.git\
?????文件??????????13??2020-05-11?11:01??smbms\.git\COMMIT_EDITMSG
?????文件??????????23??2020-05-11?11:00??smbms\.git\HEAD
?????文件?????????280??2020-05-11?12:55??smbms\.git\config
?????文件??????????73??2020-05-11?11:00??smbms\.git\description
?????目錄???????????0??2020-05-11?11:00??smbms\.git\hooks\
?????文件?????????478??2020-05-11?11:00??smbms\.git\hooks\applypatch-msg.sample
?????文件?????????896??2020-05-11?11:00??smbms\.git\hooks\commit-msg.sample
?????文件????????3079??2020-05-11?11:00??smbms\.git\hooks\fsmonitor-watchman.sample
?????文件?????????189??2020-05-11?11:00??smbms\.git\hooks\post-update.sample
?????文件?????????424??2020-05-11?11:00??smbms\.git\hooks\pre-applypatch.sample
?????文件????????1638??2020-05-11?11:00??smbms\.git\hooks\pre-commit.sample
?????文件?????????416??2020-05-11?11:00??smbms\.git\hooks\pre-merge-commit.sample
?????文件????????1348??2020-05-11?11:00??smbms\.git\hooks\pre-push.sample
?????文件????????4898??2020-05-11?11:00??smbms\.git\hooks\pre-rebase.sample
?????文件?????????544??2020-05-11?11:00??smbms\.git\hooks\pre-receive.sample
?????文件????????1492??2020-05-11?11:00??smbms\.git\hooks\prepare-commit-msg.sample
?????文件????????3610??2020-05-11?11:00??smbms\.git\hooks\update.sample
?????文件??????????65??2020-05-11?11:01??smbms\.git\index
?????目錄???????????0??2020-05-11?11:00??smbms\.git\info\
?????文件?????????240??2020-05-11?11:00??smbms\.git\info\exclude
?????目錄???????????0??2020-05-11?11:01??smbms\.git\objects\
?????目錄???????????0??2020-05-11?11:01??smbms\.git\objects\4b\
?????文件??????????15??2020-05-11?11:01??smbms\.git\objects\4b\825dc642cb6eb9a060e54bf8d69288fbee4904
?????目錄???????????0??2020-05-11?13:03??smbms\.git\objects\info\
?????目錄???????????0??2020-05-11?13:03??smbms\.git\objects\pack\
?????目錄???????????0??2020-05-11?11:00??smbms\.git\refs\
?????目錄???????????0??2020-05-11?13:03??smbms\.git\refs\heads\
?????目錄???????????0??2020-05-11?13:03??smbms\.git\refs\tags\
?????目錄???????????0??2020-05-11?10:54??smbms\.idea\
............此處省略555個文件信息