mysql的連接問題：拋出java.lang.ClassNotFoundException：com.mysql.jdbc.Driver

我除了在建立Mysql的連接到使用Java的Struts1的數據庫。這裏的代碼片段。我還添加了mysql-connector-java-5.0.8-bin.jar到web-inf/lib文件夾。還將其添加到classpath變量。mysql的連接問題：拋出java.lang.ClassNotFoundException：com.mysql.jdbc.Driver

import java.sql.DriverManager; 

import java.sql.Connection; 

import java.sql.SQLException; 


public class select { 

    public void connection() { 

    System.out.println("-------- MySQL JDBC Connection Testing ------------"); 

    try { 
     Class.forName("com.mysql.jdbc.Driver"); 
    } catch (ClassNotFoundException e) { 
     System.out.println("Where is your MySQL JDBC Driver?"); 
     e.printStackTrace(); 
     return; 
    }.

這是錯誤消息。我錯過了哪些步驟。請儘快提出建議。

-------- MySQL JDBC Connection Testing ------------ 
Where is your MySQL JDBC Driver? 
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver 
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1680) 
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1526) 
    at java.lang.Class.forName0(Native Method) 
    at java.lang.Class.forName(Unknown Source) 
    at Com.Candidjava.select.connection(select.java:14) 
    at Com.Candidjava.LoginAction.execute(LoginAction.java:26) 
    at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) 
    at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) 
    at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) 
    at org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:432) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:643) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:723) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206) 
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233) 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191) 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127) 
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:103) 
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109) 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:293) 
    at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:861) 
    at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:606) 
    at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489) 
    at java.lang.Thread.run(Unknown Source)

來源

2014-01-31 ACJ

將mysql-connector-java-5.0.8-bin.jar添加到您的tomcat安裝目錄中。當右鍵點擊你的項目並選擇構建路徑，然後選擇庫。和內部庫Apache Tomcat你應該找到你的連接器jar然後只有你的mysql將工作

來源

2014-01-31 08:35:05 user3222718

解決了TC＆Rgds – ACJ

您必須勾選正確答案，才能解決此問題。 – user3222718

嘗試這是JDBC連接mysql數據庫的例子：

import java.sql.DriverManager; 

public class Connection { 

private static java.sql.Connection conex = null; 

public static java.sql.Connection getConnectionInstance() { 
    if (conex == null) { 
     try { 
      // connection to database 
      Class.forName("com.mysql.jdbc.Driver"); 
      conex = DriverManager.getConnection(
        "jdbc:mysql://localhost:3306/databaseName","root", 
        "MySQLPassword"); 
      return conex; 
     } catch (Exception e) { 
     } 
    } 
    return conex; 
} 

}

確保你已經打開選擇在安裝過程中的端口。

來源

2014-01-31 08:33:26 OiRc

我把這個類作爲單例，所以我可以導入conex，它被用來連接到任何需要做查詢的類。 – OiRc

TC＆Rgds已解決 – ACJ

mysql的連接問題：拋出java.lang.ClassNotFoundException：com.mysql.jdbc.Driver

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