java 带有 mysql 的 Tomcat：“无法为连接 URL 'null' 创建类 '' 的 JDBC 驱动程序”
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Tomcat with mysql : " Cannot create JDBC driver of class '' for connect URL 'null' "
提问by Divij
This question has been asked and answered multiple times but it still doesn't solve my problem.
这个问题已经被多次询问和回答，但它仍然没有解决我的问题。
Host OS is Fedora 17
主机操作系统是 Fedora 17
Tomcat package tomcat-7.0.27-2.fc17.noarch
Tomcat 包 tomcat-7.0.27-2.fc17.noarch
Here is my $CATALINA_HOME/logs/catalina.out
这是我的 $CATALINA_HOME/logs/catalina.out
[DEBUG]: Failed to establish connection with datastore
org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot create JDBC driver of class '' for connect URL 'null'
at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createConnectionFactory(BasicDataSource.java:1452)
at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createDataSource(BasicDataSource.java:1371)
at org.apache.tomcat.dbcp.dbcp.BasicDataSource.getConnection(BasicDataSource.java:1044)
...
...
Caused by: java.sql.SQLException: No suitable driver
at java.sql.DriverManager.getDriver(DriverManager.java:289)
at org.apache.tomcat.dbcp.dbcp.BasicDataSource.createConnectionFactory(BasicDataSource.java:1437)
...
Here is my $CATALINA_HOME/conf/Catalina/localhost/ABC/ABC.xml
这是我的 $CATALINA_HOME/conf/Catalina/localhost/ABC/ABC.xml
<Context path="/ABC">
<!-- maxActive: Maximum number of dB connections in pool. Make sure you
configure your mysqld max_connections large enough to handle
all of your db connections. Set to -1 for no limit.
-->
<!-- maxIdle: Maximum number of idle dB connections to retain in pool.
Set to -1 for no limit. See also the DBCP documentation on this
and the minEvictableIdleTimeMillis configuration parameter.
-->
<!-- maxWait: Maximum time to wait for a dB connection to become available
in ms, in this example 10 seconds. An Exception is thrown if
this timeout is exceeded. Set to -1 to wait indefinitely.
-->
<!-- username and password: DB username and KeyDB password key (not the password itself) -->
<!-- driverClassName: Class name for the JDBC KeyDB wrappers. These wrappers
replace the 'mysql_keydb_key' with its corresponding value from KeyDB
-->
<!-- url: The JDBC connection url for connecting to your MySQL dB.
The autoReconnect=true argument to the url makes sure that the
mm.mysql JDBC Driver will automatically reconnect if mysqld closed the
connection. mysqld by default closes idle connections after 8 hours.
-->
<Resource name="jdbc/last_db" auth="Container" type="javax.sql.DataSource" maxActive="100" maxIdle="30" maxWait="10000" username="****" password="****" driverClassName="com.mysql.jdbc.Driver" url="jdbc:mysql://localhost:3306/last_db"/>
</Context>
Here is my $CATALINA_HOME/lib directory
这是我的 $CATALINA_HOME/lib 目录
$ ls /usr/share/tomcat/lib
annotations-api.jar commons-collections.jar log4j.jar tomcat-i18n-es.jar tomcat-servlet-3.0-api.jar
apache-commons-dbcp.jar commons-dbcp.jar mysql-connector-java-5.1.0.jar tomcat-i18n-fr.jar tomcat-util.jar
catalina-ant.jar commons-logging-1.1.1.jar tomcat-api.jar tomcat-i18n-ja.jar
catalina-ha.jar jasper-el.jar tomcat-coyote.jar tomcat-jdbc.jar
catalina.jar jasper.jar tomcat-dbcp.jar tomcat-jsp-2.2-api.jar
catalina-tribes.jar jasper-jdt.jar tomcat-el-2.2-api.jar tomcat-juli.jar
Here is my WEB-INF/web.xml
这是我的 WEB-INF/web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
version="2.5">
<servlet>
<servlet-name>jersey</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>jersey</servlet-name>
<url-pattern>/v1/*</url-pattern>
</servlet-mapping>
<resource-ref>
<description>DB Connection</description>
<res-ref-name>jdbc/last_db</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
</web-app>
Executing code:
执行代码：
try {
Context initContext = new InitialContext();
Context envContext = (Context)initContext.lookup("java:/comp/env");
dataSource = (DataSource) envContext.lookup("jdbc/"+dbName);
} catch (NamingException ex) {
System.out.println("[DEBUG]: Failed to initiate JDBC context");
ex.printStackTrace();
return;
}
try {
connection = dataSource.getConnection();
} catch (SQLException ex){
System.out.println("[DEBUG]: Failed to establish connection with datastore");
ex.printStackTrace();
return;
} catch (ClassNotFoundException ww){
ww.printStackTrace();
}
The mysql-connector jar seems to be available in WEB-INF/lib
mysql-connector jar 似乎在 WEB-INF/lib 中可用
$ jar tf ABC.war | grep mysql-connector
WEB-INF/lib/mysql-connector-java-5.1.0.jar
I don't know if this is useful or not but here is the listening port information for port 3306
我不知道这是否有用，但这里是端口 3306 的侦听端口信息
$ netstat -tln
Active Internet connections (only servers)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN
采纳答案by Divij
I feel like banging my head on the table.
我想把头撞在桌子上。
The problem was that instead of keeping the ABC.xml $CATALINA_HOME/conf/Catalina/localhost/ABC/ABC.xml It is supposed to be kept here: $CATALINA_HOME/conf/Catalina/localhost/ABC.xml
问题是，而不是保留 ABC.xml $CATALINA_HOME/conf/Catalina/localhost/ABC/ABC.xml 它应该保留在这里： $CATALINA_HOME/conf/Catalina/localhost/ABC.xml
The StackTrace was very misleading regarding error with the connector driver.
StackTrace 在连接器驱动程序错误方面非常具有误导性。
