本文為大家分享了java使用jdbc連接數據庫的具體代碼,供大家參考,具體內容如下
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package com.tr.jdbc; import java.sql.connection; import java.sql.resultset; import java.sql.sqlexception; import java.sql.statement; import org.apache.commons.dbcp2.basicdatasource; public class collectionfactory { private final static string dbdriver = "com.mysql.jdbc.driver" ; private final static string dburl= "jdbc:mysql://localhost:3306/xtest?useunicode=true&characterencoding=utf-8" ; private final static string dbuser= "root" ; private final static string dbpwd= "root" ; private static basicdatasource datasource; //創建dbcp的簡單數據源并初始化相關屬性 static { datasource = new basicdatasource(); datasource.setdriverclassname(dbdriver); datasource.seturl(dburl); datasource.setusername(dbuser); datasource.setpassword(dbpwd); //指定數據庫連接池初始化連接數 datasource.setinitialsize( 10 ); //設定同時向數據庫申請的最大連接數 datasource.setmaxtotal( 50 ); //設置連接池中保持的最少連接數量 datasource.setminidle( 5 ); //其他屬相...參考apache的公開文檔 } //創建數據庫連接對象--并且多線程并發處理(注意connection導的是java.sql的包) public static synchronized connection creatconnection(){ connection conn = null ; if (datasource!= null &&!datasource.isclosed()){ try { conn = datasource.getconnection(); } catch (sqlexception e) { e.printstacktrace(); } } return conn; } public static void main(string[] args) { string sql = "select * from s_t_user" ; connection conn = creatconnection(); statement statement = null ; resultset resultset = null ; try { statement = conn.createstatement(); resultset= statement.executequery(sql); int row = 0 ; while (resultset.next()){ row++; system.out.println( "記錄行" +row+ "col2:" +resultset.getstring( 2 )); } } catch (sqlexception e) { e.printstacktrace(); } finally { if (conn!= null ) { try { conn.close(); } catch (sqlexception e) { e.printstacktrace(); } } } } } |
一定要注意不能導錯包,我剛才就是因為basicdatasource的包導錯了,寫成了import org.apache.tomcat.dbcp.dbcp2.basicdatasource;應該是import org.apache.commons.dbcp2.basicdatasource; 而一直報這樣的錯誤:
以上就是本文的全部內容,希望對大家的學習有所幫助,也希望大家多多支持服務器之家。
原文鏈接:https://blog.csdn.net/xusheng_mr/article/details/70947768