Name jdbc is not bound in this Context in Tomcat - java

I'm having trouble with JDBC Connection Pooling, I've done all the same with explained here: JNDI Resources HOW-TO, and here is also question (the same configuration with mine) regarding this topic which has not been resolved, I think.
What else should I consider?

I hope you have done the ResourceLink configuration to your webapp, too.
<Context>
...
<ResourceLink global="jdbc/MyDS" name="jdbc/MyDS" type="javax.sql.DataSource" />
...
</Context>

I had this error when the JDBC driver was deleted from classpath. In my setup, Tomcat expected libraries in a special directory, which was filled by Maven executing a special target. Whenever I cleaned and forgot to execute the Maven's target prior to running Tomcat, I had precisely this error.

Related

"Losing" dependency why building jar with maven [duplicate]

I'm trying to add a database-enabled JSP to an existing Tomcat 5.5 application (GeoServer 2.0.0, if that helps).
The app itself talks to Postgres just fine, so I know that the database is up, user can access it, all that good stuff. What I'm trying to do is a database query in a JSP that I've added. I've used the config example in the Tomcat datasource example pretty much out of the box. The requisite taglibs are in the right place -- no errors occur if I just have the taglib refs, so it's finding those JARs. The postgres jdbc driver, postgresql-8.4.701.jdbc3.jar is in $CATALINA_HOME/common/lib.
Here's the top of the JSP:
<%# taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql" %>
<%# taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<sql:query var="rs" dataSource="jdbc/mmas">
select current_validstart as ValidTime from runoff_forecast_valid_time
</sql:query>
The relevant section from $CATALINA_HOME/conf/server.xml, inside the <Host> which is in turn within <Engine>:
<Context path="/gs2" allowLinking="true">
<Resource name="jdbc/mmas" type="javax.sql.Datasource"
auth="Container" driverClassName="org.postgresql.Driver"
maxActive="100" maxIdle="30" maxWait="10000"
username="mmas" password="very_secure_yess_precious!"
url="jdbc:postgresql//localhost:5432/mmas" />
</Context>
These lines are the last in the tag in webapps/gs2/WEB-INF/web.xml:
<resource-ref>
<description>
The database resource for the MMAS PostGIS database
</description>
<res-ref-name>
jdbc/mmas
</res-ref-name>
<res-type>
javax.sql.DataSource
</res-type>
<res-auth>
Container
</res-auth>
</resource-ref>
Finally, the exception:
exception
org.apache.jasper.JasperException: Unable to get connection, DataSource invalid: "java.sql.SQLException: No suitable driver"
[...wads of ensuing goo elided]
The infamous java.sql.SQLException: No suitable driver found
This exception can have basically two causes:
1. JDBC driver is not loaded
In case of Tomcat, you need to ensure that the JDBC driver is placed in server's own /lib folder.
Or, when you're actually not using a server-managed connection pool data source, but are manually fiddling around with DriverManager#getConnection() in WAR, then you need to place the JDBC driver in WAR's /WEB-INF/lib and perform ..
Class.forName("com.example.jdbc.Driver");
.. in your code before the first DriverManager#getConnection() call whereby you make sure that you do not swallow/ignore any ClassNotFoundException which can be thrown by it and continue the code flow as if nothing exceptional happened. See also Where do I have to place the JDBC driver for Tomcat's connection pool?
Other servers have a similar way of placing the JAR file:
GlassFish: put the JAR file in /glassfish/lib
WildFly: put the JAR file in /standalone/deployments
2. Or, JDBC URL is in wrong syntax
You need to ensure that the JDBC URL is conform the JDBC driver documentation and keep in mind that it's usually case sensitive. When the JDBC URL does not return true for Driver#acceptsURL() for any of the loaded drivers, then you will also get exactly this exception.
In case of PostgreSQL it is documented here.
With JDBC, a database is represented by a URL (Uniform Resource Locator). With PostgreSQL™, this takes one of the following forms:
jdbc:postgresql:database
jdbc:postgresql://host/database
jdbc:postgresql://host:port/database
In case of MySQL it is documented here.
The general format for a JDBC URL for connecting to a MySQL server is as follows, with items in square brackets ([ ]) being optional:
jdbc:mysql://[host1][:port1][,[host2][:port2]]...[/[database]] » [?propertyName1=propertyValue1[&propertyName2=propertyValue2]...]
In case of Oracle it is documented here.
There are 2 URL syntax, old syntax which will only work with SID and the new one with Oracle service name.
Old syntax jdbc:oracle:thin:#[HOST][:PORT]:SID
New syntax jdbc:oracle:thin:#//[HOST][:PORT]/SERVICE
See also:
Where do I have to place the JDBC driver for Tomcat's connection pool?
How to install JDBC driver in Eclipse web project without facing java.lang.ClassNotFoundexception
How should I connect to JDBC database / datasource in a servlet based application?
What is the difference between "Class.forName()" and "Class.forName().newInstance()"?
Connect Java to a MySQL database
I've forgot to add the PostgreSQL JDBC Driver into my project (Mvnrepository).
Gradle:
// http://mvnrepository.com/artifact/postgresql/postgresql
compile group: 'postgresql', name: 'postgresql', version: '9.0-801.jdbc4'
Maven:
<dependency>
<groupId>postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>9.0-801.jdbc4</version>
</dependency>
You can also download the JAR and import to your project manually.
url="jdbc:postgresql//localhost:5432/mmas"
That URL looks wrong, do you need the following?
url="jdbc:postgresql://localhost:5432/mmas"
I faced the similar issue.
My Project in context is Dynamic Web Project(Java 8 + Tomcat 8) and error is for PostgreSQL Driver exception: No suitable driver found
It got resolved by adding Class.forName("org.postgresql.Driver") before calling getConnection() method
Here is my Sample Code:
try {
Connection conn = null;
Class.forName("org.postgresql.Driver");
conn = DriverManager.getConnection("jdbc:postgresql://" + host + ":" + port + "/?preferQueryMode="
+ sql_auth,sql_user , sql_password);
} catch (Exception e) {
System.out.println("Failed to create JDBC db connection " + e.toString() + e.getMessage());
}
I found the followig tip helpful, to eliminate this issue in Tomcat -
be sure to load the driver first doing a Class.forName("
org.postgresql.Driver"); in your code.
This is from the post - https://www.postgresql.org/message-id/e13c14ec050510103846db6b0e#mail.gmail.com
The jdbc code worked fine as a standalone program but, in TOMCAT it gave the error -'No suitable driver found'
No matter how old this thread becomes, people would continue to face this issue.
My Case: I have the latest (at the time of posting) OpenJDK and maven setup. I had tried all methods given above, with/out maven and even solutions on sister posts on StackOverflow. I am not using any IDE or anything else, running from bare CLI to demonstrate only the core logic.
Here's what finally worked.
Download the driver from the official site. (for me it was MySQL https://www.mysql.com/products/connector/). Use your flavour here.
Unzip the given jar file in the same directory as your java project. You would get a directory structure like this. If you look carefully, this exactly relates to what we try to do using Class.forName(....). The file that we want is the com/mysql/jdbc/Driver.class
Compile the java program containing the code.
javac App.java
Now load the director as a module by running
java --module-path com/mysql/jdbc -cp ./ App
This would load the (extracted) package manually, and your java program would find the required Driver class.
Note that this was done for the mysql driver, other drivers might require minor changes.
If your vendor provides a .deb image, you can get the jar from /usr/share/java/your-vendor-file-here.jar
Summary:
Soln2 (recommend)::
1 . put mysql-connector-java-8.0.28.jar file in the <where you install your Tomcat>/lib.
Soln1::
1 . put mysql-connector-java-8.0.28.jar file in the WEB-INF/lib.
2 . use Class.forName("com.mysql.cj.jdbc.Driver"); in your Servlet Java code.
Soln1 (Ori Ans) //-20220304
In short:
make sure you have the mysql-connector-java-8.0.28.jar file in the WEB-INF/lib
make sure you use the Class.forName("com.mysql.cj.jdbc.Driver");
additional notes (not important), base on my trying (could be wrong)::
1.1 putting the jar directly inside the Java build path doesnt work
1.2. putting the jar in Data management > Driver Def > MySQL JDBC Driver > then add it as library to Java Build path doesnt work.
1.3 => it has to be inside the WEB-INF/lib (I dont know why)
1.4 using version mysql-connector-java-8.0.28.jar works, only version 5.1 available in Eclipse MySQL JDBC Driver setting doesnt matter, ignore it.
<see How to connect to MySql 8.0 database using Eclipse Database Management Perspective >
Class.forName("com.mysql.cj.jdbc.Driver");
Class.forName("com.mysql.jdbc.Driver");
both works,
but the Class.forName("com.mysql.jdbc.Driver"); is deprecated.
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
<see https://www.yawintutor.com/no-suitable-driver-found-for-jdbcmysql-localhost3306-testdb/ >
If you want to connect to a MySQL database, you can use the type-4 driver named Connector/} that's available for free from the MySQL website. However, this driver is typically included in Tomcat's lib directory. As a result, you don't usually need to download this driver from the MySQL site.
-- Murach’s Java Servlets and JSP
I cant find the driver in Tomcat that the author is talking about, I need to use the mysql-connector-java-8.0.28.jar.
<(striked-out) see updated answer soln2 below>
If you're working with an older version of Java, though, you need to use the forName method of the Class class to explicitly load the driver before you call the getConnection method
Even with JDBC 4.0, you sometimes get a message that says, "No suitable driver found." In that case, you can use the forName method of the Class class to explicitly load the driver. However, if automatic driver loading works, it usually makes sense to remove this method call from your code.
How to load a MySQL database driver prior to JDBC 4.0
Class.forName{"com.mysql.jdbc.Driver");
-- Murach’s Java Servlets and JSP
I have to use Class.forName("com.mysql.cj.jdbc.Driver"); in my system, no automatic class loading. Not sure why.
<(striked-out) see updated answer soln2 below>
When I am using a normal Java Project instead of a Dynamic Web Project in Eclipse,
I only need to add the mysql-connector-java-8.0.28.jar to Java Build Path directly,
then I can connect to the JDBC with no problem.
However, if I am using Dynamic Web Project (which is in this case), those 2 strict rules applies (jar position & class loading).
<see TOMCAT ON ECLIPSE java.sql.SQLException: No suitable driver found for jdbc:mysql >
Soln2 (Updated Ans) //-20220305_12
In short:
1 . put mysql-connector-java-8.0.28.jar file in the <where you install your Tomcat>/lib.
eg: G:\pla\Java\apache-tomcat-10.0.16\lib\mysql-connector-java-8.0.28.jar
(and for an Eclipse Dynamic Web Project, the jar will then be automatically put inside in your project's Java build path > Server Runtime [Apache Tomcat v10.0].)
Additional notes::
for soln1::
put mysql-connector-java-8.0.28.jar file in the WEB-INF/lib.
use Class.forName("com.mysql.cj.jdbc.Driver"); in your Servlet Java code.
this will create an WARNING:
WARNING: The web application [LearnJDBC] appears to have started a thread named [mysql-cj-abandoned-connection-cleanup] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
<see The web application [] appears to have started a thread named [Abandoned connection cleanup thread] com.mysql.jdbc.AbandonedConnectionCleanupThread >
and that answer led me to soln2.
for soln2::
put mysql-connector-java-8.0.28.jar file in the <where you install your Tomcat>/lib.
this will create an INFO:
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
you can just ignore it.
<see How to fix "JARs that were scanned but no TLDs were found in them " in Tomcat 9.0.0M10 >
(you should now understand what Murach’s Java Servlets and JSP was talking about: the jar in Tomcat/lib & the no need for Class.forName("com.mysql.cj.jdbc.Driver");)
to kinda fix it //-20220307_23
Tomcat 8.5. Inside catalina.properties, located in the /conf directory set:
tomcat.util.scan.StandardJarScanFilter.jarsToSkip=\*.jar
How to fix JSP compiler warning: one JAR was scanned for TLDs yet contained no TLDs?
It might be worth noting that this can also occur when Windows blocks downloads that it considers to be unsafe. This can be addressed by right-clicking the jar file (such as ojdbc7.jar), and checking the 'Unblock' box at the bottom.
Windows JAR File Properties Dialog:
As well as adding the MySQL JDBC connector ensure the context.xml (if not unpacked in the Tomcat webapps folder) with your DB connection definitions are included within Tomcats conf directory.
A very silly mistake which could be possible resulting is adding of space at the start of the JDBC URL connection.
What I mean is:-
suppose u have bymistake given the jdbc url like
String jdbcUrl=" jdbc:mysql://localhost:3306/web_customer_tracker?useSSL=false&serverTimeZone=UTC";
(Notice there is a space in the staring of the url, this will make the error)
the correct way should be:
String jdbcUrl="jdbc:mysql://localhost:3306/web_customer_tracker?useSSL=false&serverTimeZone=UTC";
(Notice no space in the staring, you may give space at the end of the url but it is safe not to)
Run java with CLASSPATH environmental variable pointing to driver's JAR file, e.g.
CLASSPATH='.:drivers/mssql-jdbc-6.2.1.jre8.jar' java ConnectURL
Where drivers/mssql-jdbc-6.2.1.jre8.jar is the path to driver file (e.g. JDBC for for SQL Server).
The ConnectURL is the sample app from that driver (samples/connections/ConnectURL.java), compiled via javac ConnectURL.java.
I was using jruby, in my case I created under config/initializers
postgres_driver.rb
$CLASSPATH << '~/.rbenv/versions/jruby-1.7.17/lib/ruby/gems/shared/gems/jdbc-postgres-9.4.1200/lib/postgresql-9.4-1200.jdbc4.jar'
or wherever your driver is, and that's it !
I had this exact issue when developing a Spring Boot application in STS, but ultimately deploying the packaged war to WebSphere(v.9). Based on previous answers my situation was unique. ojdbc8.jar was in my WEB-INF/lib folder with Parent Last class loading set, but always it says it failed to find the suitable driver.
My ultimate issue was that I was using the incorrect DataSource class because I was just following along with online tutorials/examples. Found the hint thanks to David Dai comment on his own question here: Spring JDBC Could not load JDBC driver class [oracle.jdbc.driver.OracleDriver]
Also later found spring guru example with Oracle specific driver: https://springframework.guru/configuring-spring-boot-for-oracle/
Example that throws error using org.springframework.jdbc.datasource.DriverManagerDataSource based on generic examples.
#Config
#EnableTransactionManagement
public class appDataConfig {
\* Other Bean Defs *\
#Bean
public DataSource dataSource() {
// configure and return the necessary JDBC DataSource
DriverManagerDataSource dataSource = new DriverManagerDataSource("jdbc:oracle:thin:#//HOST:PORT/SID", "user", "password");
dataSource.setSchema("MY_SCHEMA");
return dataSource;
}
}
And the corrected exapmle using a oracle.jdbc.pool.OracleDataSource:
#Config
#EnableTransactionManagement
public class appDataConfig {
/* Other Bean Defs */
#Bean
public DataSource dataSource() {
// configure and return the necessary JDBC DataSource
OracleDataSource datasource = null;
try {
datasource = new OracleDataSource();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
datasource.setURL("jdbc:oracle:thin:#//HOST:PORT/SID");
datasource.setUser("user");
datasource.setPassword("password");
return datasource;
}
}
I was having the same issue with mysql datasource using spring data that would work outside but gave me this error when deployed on tomcat.
The error went away when I added the driver jar mysql-connector-java-8.0.16.jar to the jres lib/ext folder
However I did not want to do this in production for fear of interfering with other applications. Explicity defining the driver class solved this issue for me
spring.datasource.driver-class-name: com.mysql.cj.jdbc.Driver
You will get this same error if there is not a Resource definition provided somewhere for your app -- most likely either in the central context.xml, or individual context file in conf/Catalina/localhost. And if using individual context files, beware that Tomcat freely deletes them anytime you remove/undeploy the corresponding .war file.
For me the same error occurred while connecting to postgres while creating a dataframe from table .It was caused due to,the missing dependency. jdbc dependency was not set .I was using maven for the build ,so added the required dependency to the pom file from maven dependency
jdbc dependency
For me adding below dependency to pom.xml file just solved like magic! I had no mysql connector dependency and even adding mssql jdbc jar file to build path did not work either.
<dependency>
<groupId>com.microsoft.sqlserver</groupId>
<artifactId>mssql-jdbc</artifactId>
<version>9.4.0.jre11</version>
</dependency>
In my case I was working on a Java project with Maven and encountered this error.
In your pom.xml file make sure you have this dependencies
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.11</version>
</dependency>
</dependencies>
and where you create connection have something like this
public Connection createConnection() {
try {
String url = "jdbc:mysql://localhost:3306/yourDatabaseName";
String username = "root"; //your my sql username here
String password = "1234"; //your mysql password here
Class.forName("com.mysql.cj.jdbc.Driver");
return DriverManager.getConnection(url, username, password);
} catch (SQLException | ClassNotFoundException e) {
e.printStackTrace();
}
return null;
}
faced same issue. in my case ':' colon before '//' (jdbc:mysql://localhost:3306/dbname) was missing, and it just fixed the problem.
make sure : and // are placed properly.
I ran into the same error. In my case, the JDBC URL was correct, but the issue was with classpath. However, adding MySQL connector's JAR file to the -classpath or -cp (or, in the case of an IDE, as a library) doesn't resolve the issue. So I will have to move the JAR file to the location of Java bytecode and run java -cp :mysql_connector.jar to make this work. If someone runs into the same issue as mine, I'm leaving this here.
I encountered this issue by putting a XML file into the src/main/resources wrongly, I deleted it and then all back to normal.

java.sql.SQLException: Cannot create JDBC driver of class '' for connect URL 'null' [duplicate]

I'm trying to add a database-enabled JSP to an existing Tomcat 5.5 application (GeoServer 2.0.0, if that helps).
The app itself talks to Postgres just fine, so I know that the database is up, user can access it, all that good stuff. What I'm trying to do is a database query in a JSP that I've added. I've used the config example in the Tomcat datasource example pretty much out of the box. The requisite taglibs are in the right place -- no errors occur if I just have the taglib refs, so it's finding those JARs. The postgres jdbc driver, postgresql-8.4.701.jdbc3.jar is in $CATALINA_HOME/common/lib.
Here's the top of the JSP:
<%# taglib uri="http://java.sun.com/jsp/jstl/sql" prefix="sql" %>
<%# taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<sql:query var="rs" dataSource="jdbc/mmas">
select current_validstart as ValidTime from runoff_forecast_valid_time
</sql:query>
The relevant section from $CATALINA_HOME/conf/server.xml, inside the <Host> which is in turn within <Engine>:
<Context path="/gs2" allowLinking="true">
<Resource name="jdbc/mmas" type="javax.sql.Datasource"
auth="Container" driverClassName="org.postgresql.Driver"
maxActive="100" maxIdle="30" maxWait="10000"
username="mmas" password="very_secure_yess_precious!"
url="jdbc:postgresql//localhost:5432/mmas" />
</Context>
These lines are the last in the tag in webapps/gs2/WEB-INF/web.xml:
<resource-ref>
<description>
The database resource for the MMAS PostGIS database
</description>
<res-ref-name>
jdbc/mmas
</res-ref-name>
<res-type>
javax.sql.DataSource
</res-type>
<res-auth>
Container
</res-auth>
</resource-ref>
Finally, the exception:
exception
org.apache.jasper.JasperException: Unable to get connection, DataSource invalid: "java.sql.SQLException: No suitable driver"
[...wads of ensuing goo elided]
The infamous java.sql.SQLException: No suitable driver found
This exception can have basically two causes:
1. JDBC driver is not loaded
In case of Tomcat, you need to ensure that the JDBC driver is placed in server's own /lib folder.
Or, when you're actually not using a server-managed connection pool data source, but are manually fiddling around with DriverManager#getConnection() in WAR, then you need to place the JDBC driver in WAR's /WEB-INF/lib and perform ..
Class.forName("com.example.jdbc.Driver");
.. in your code before the first DriverManager#getConnection() call whereby you make sure that you do not swallow/ignore any ClassNotFoundException which can be thrown by it and continue the code flow as if nothing exceptional happened. See also Where do I have to place the JDBC driver for Tomcat's connection pool?
Other servers have a similar way of placing the JAR file:
GlassFish: put the JAR file in /glassfish/lib
WildFly: put the JAR file in /standalone/deployments
2. Or, JDBC URL is in wrong syntax
You need to ensure that the JDBC URL is conform the JDBC driver documentation and keep in mind that it's usually case sensitive. When the JDBC URL does not return true for Driver#acceptsURL() for any of the loaded drivers, then you will also get exactly this exception.
In case of PostgreSQL it is documented here.
With JDBC, a database is represented by a URL (Uniform Resource Locator). With PostgreSQL™, this takes one of the following forms:
jdbc:postgresql:database
jdbc:postgresql://host/database
jdbc:postgresql://host:port/database
In case of MySQL it is documented here.
The general format for a JDBC URL for connecting to a MySQL server is as follows, with items in square brackets ([ ]) being optional:
jdbc:mysql://[host1][:port1][,[host2][:port2]]...[/[database]] » [?propertyName1=propertyValue1[&propertyName2=propertyValue2]...]
In case of Oracle it is documented here.
There are 2 URL syntax, old syntax which will only work with SID and the new one with Oracle service name.
Old syntax jdbc:oracle:thin:#[HOST][:PORT]:SID
New syntax jdbc:oracle:thin:#//[HOST][:PORT]/SERVICE
See also:
Where do I have to place the JDBC driver for Tomcat's connection pool?
How to install JDBC driver in Eclipse web project without facing java.lang.ClassNotFoundexception
How should I connect to JDBC database / datasource in a servlet based application?
What is the difference between "Class.forName()" and "Class.forName().newInstance()"?
Connect Java to a MySQL database
I've forgot to add the PostgreSQL JDBC Driver into my project (Mvnrepository).
Gradle:
// http://mvnrepository.com/artifact/postgresql/postgresql
compile group: 'postgresql', name: 'postgresql', version: '9.0-801.jdbc4'
Maven:
<dependency>
<groupId>postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>9.0-801.jdbc4</version>
</dependency>
You can also download the JAR and import to your project manually.
url="jdbc:postgresql//localhost:5432/mmas"
That URL looks wrong, do you need the following?
url="jdbc:postgresql://localhost:5432/mmas"
I faced the similar issue.
My Project in context is Dynamic Web Project(Java 8 + Tomcat 8) and error is for PostgreSQL Driver exception: No suitable driver found
It got resolved by adding Class.forName("org.postgresql.Driver") before calling getConnection() method
Here is my Sample Code:
try {
Connection conn = null;
Class.forName("org.postgresql.Driver");
conn = DriverManager.getConnection("jdbc:postgresql://" + host + ":" + port + "/?preferQueryMode="
+ sql_auth,sql_user , sql_password);
} catch (Exception e) {
System.out.println("Failed to create JDBC db connection " + e.toString() + e.getMessage());
}
I found the followig tip helpful, to eliminate this issue in Tomcat -
be sure to load the driver first doing a Class.forName("
org.postgresql.Driver"); in your code.
This is from the post - https://www.postgresql.org/message-id/e13c14ec050510103846db6b0e#mail.gmail.com
The jdbc code worked fine as a standalone program but, in TOMCAT it gave the error -'No suitable driver found'
No matter how old this thread becomes, people would continue to face this issue.
My Case: I have the latest (at the time of posting) OpenJDK and maven setup. I had tried all methods given above, with/out maven and even solutions on sister posts on StackOverflow. I am not using any IDE or anything else, running from bare CLI to demonstrate only the core logic.
Here's what finally worked.
Download the driver from the official site. (for me it was MySQL https://www.mysql.com/products/connector/). Use your flavour here.
Unzip the given jar file in the same directory as your java project. You would get a directory structure like this. If you look carefully, this exactly relates to what we try to do using Class.forName(....). The file that we want is the com/mysql/jdbc/Driver.class
Compile the java program containing the code.
javac App.java
Now load the director as a module by running
java --module-path com/mysql/jdbc -cp ./ App
This would load the (extracted) package manually, and your java program would find the required Driver class.
Note that this was done for the mysql driver, other drivers might require minor changes.
If your vendor provides a .deb image, you can get the jar from /usr/share/java/your-vendor-file-here.jar
Summary:
Soln2 (recommend)::
1 . put mysql-connector-java-8.0.28.jar file in the <where you install your Tomcat>/lib.
Soln1::
1 . put mysql-connector-java-8.0.28.jar file in the WEB-INF/lib.
2 . use Class.forName("com.mysql.cj.jdbc.Driver"); in your Servlet Java code.
Soln1 (Ori Ans) //-20220304
In short:
make sure you have the mysql-connector-java-8.0.28.jar file in the WEB-INF/lib
make sure you use the Class.forName("com.mysql.cj.jdbc.Driver");
additional notes (not important), base on my trying (could be wrong)::
1.1 putting the jar directly inside the Java build path doesnt work
1.2. putting the jar in Data management > Driver Def > MySQL JDBC Driver > then add it as library to Java Build path doesnt work.
1.3 => it has to be inside the WEB-INF/lib (I dont know why)
1.4 using version mysql-connector-java-8.0.28.jar works, only version 5.1 available in Eclipse MySQL JDBC Driver setting doesnt matter, ignore it.
<see How to connect to MySql 8.0 database using Eclipse Database Management Perspective >
Class.forName("com.mysql.cj.jdbc.Driver");
Class.forName("com.mysql.jdbc.Driver");
both works,
but the Class.forName("com.mysql.jdbc.Driver"); is deprecated.
Loading class `com.mysql.jdbc.Driver'. This is deprecated. The new driver class is `com.mysql.cj.jdbc.Driver'. The driver is automatically registered via the SPI and manual loading of the driver class is generally unnecessary.
<see https://www.yawintutor.com/no-suitable-driver-found-for-jdbcmysql-localhost3306-testdb/ >
If you want to connect to a MySQL database, you can use the type-4 driver named Connector/} that's available for free from the MySQL website. However, this driver is typically included in Tomcat's lib directory. As a result, you don't usually need to download this driver from the MySQL site.
-- Murach’s Java Servlets and JSP
I cant find the driver in Tomcat that the author is talking about, I need to use the mysql-connector-java-8.0.28.jar.
<(striked-out) see updated answer soln2 below>
If you're working with an older version of Java, though, you need to use the forName method of the Class class to explicitly load the driver before you call the getConnection method
Even with JDBC 4.0, you sometimes get a message that says, "No suitable driver found." In that case, you can use the forName method of the Class class to explicitly load the driver. However, if automatic driver loading works, it usually makes sense to remove this method call from your code.
How to load a MySQL database driver prior to JDBC 4.0
Class.forName{"com.mysql.jdbc.Driver");
-- Murach’s Java Servlets and JSP
I have to use Class.forName("com.mysql.cj.jdbc.Driver"); in my system, no automatic class loading. Not sure why.
<(striked-out) see updated answer soln2 below>
When I am using a normal Java Project instead of a Dynamic Web Project in Eclipse,
I only need to add the mysql-connector-java-8.0.28.jar to Java Build Path directly,
then I can connect to the JDBC with no problem.
However, if I am using Dynamic Web Project (which is in this case), those 2 strict rules applies (jar position & class loading).
<see TOMCAT ON ECLIPSE java.sql.SQLException: No suitable driver found for jdbc:mysql >
Soln2 (Updated Ans) //-20220305_12
In short:
1 . put mysql-connector-java-8.0.28.jar file in the <where you install your Tomcat>/lib.
eg: G:\pla\Java\apache-tomcat-10.0.16\lib\mysql-connector-java-8.0.28.jar
(and for an Eclipse Dynamic Web Project, the jar will then be automatically put inside in your project's Java build path > Server Runtime [Apache Tomcat v10.0].)
Additional notes::
for soln1::
put mysql-connector-java-8.0.28.jar file in the WEB-INF/lib.
use Class.forName("com.mysql.cj.jdbc.Driver"); in your Servlet Java code.
this will create an WARNING:
WARNING: The web application [LearnJDBC] appears to have started a thread named [mysql-cj-abandoned-connection-cleanup] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:
<see The web application [] appears to have started a thread named [Abandoned connection cleanup thread] com.mysql.jdbc.AbandonedConnectionCleanupThread >
and that answer led me to soln2.
for soln2::
put mysql-connector-java-8.0.28.jar file in the <where you install your Tomcat>/lib.
this will create an INFO:
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
you can just ignore it.
<see How to fix "JARs that were scanned but no TLDs were found in them " in Tomcat 9.0.0M10 >
(you should now understand what Murach’s Java Servlets and JSP was talking about: the jar in Tomcat/lib & the no need for Class.forName("com.mysql.cj.jdbc.Driver");)
to kinda fix it //-20220307_23
Tomcat 8.5. Inside catalina.properties, located in the /conf directory set:
tomcat.util.scan.StandardJarScanFilter.jarsToSkip=\*.jar
How to fix JSP compiler warning: one JAR was scanned for TLDs yet contained no TLDs?
It might be worth noting that this can also occur when Windows blocks downloads that it considers to be unsafe. This can be addressed by right-clicking the jar file (such as ojdbc7.jar), and checking the 'Unblock' box at the bottom.
Windows JAR File Properties Dialog:
As well as adding the MySQL JDBC connector ensure the context.xml (if not unpacked in the Tomcat webapps folder) with your DB connection definitions are included within Tomcats conf directory.
A very silly mistake which could be possible resulting is adding of space at the start of the JDBC URL connection.
What I mean is:-
suppose u have bymistake given the jdbc url like
String jdbcUrl=" jdbc:mysql://localhost:3306/web_customer_tracker?useSSL=false&serverTimeZone=UTC";
(Notice there is a space in the staring of the url, this will make the error)
the correct way should be:
String jdbcUrl="jdbc:mysql://localhost:3306/web_customer_tracker?useSSL=false&serverTimeZone=UTC";
(Notice no space in the staring, you may give space at the end of the url but it is safe not to)
Run java with CLASSPATH environmental variable pointing to driver's JAR file, e.g.
CLASSPATH='.:drivers/mssql-jdbc-6.2.1.jre8.jar' java ConnectURL
Where drivers/mssql-jdbc-6.2.1.jre8.jar is the path to driver file (e.g. JDBC for for SQL Server).
The ConnectURL is the sample app from that driver (samples/connections/ConnectURL.java), compiled via javac ConnectURL.java.
I was using jruby, in my case I created under config/initializers
postgres_driver.rb
$CLASSPATH << '~/.rbenv/versions/jruby-1.7.17/lib/ruby/gems/shared/gems/jdbc-postgres-9.4.1200/lib/postgresql-9.4-1200.jdbc4.jar'
or wherever your driver is, and that's it !
I had this exact issue when developing a Spring Boot application in STS, but ultimately deploying the packaged war to WebSphere(v.9). Based on previous answers my situation was unique. ojdbc8.jar was in my WEB-INF/lib folder with Parent Last class loading set, but always it says it failed to find the suitable driver.
My ultimate issue was that I was using the incorrect DataSource class because I was just following along with online tutorials/examples. Found the hint thanks to David Dai comment on his own question here: Spring JDBC Could not load JDBC driver class [oracle.jdbc.driver.OracleDriver]
Also later found spring guru example with Oracle specific driver: https://springframework.guru/configuring-spring-boot-for-oracle/
Example that throws error using org.springframework.jdbc.datasource.DriverManagerDataSource based on generic examples.
#Config
#EnableTransactionManagement
public class appDataConfig {
\* Other Bean Defs *\
#Bean
public DataSource dataSource() {
// configure and return the necessary JDBC DataSource
DriverManagerDataSource dataSource = new DriverManagerDataSource("jdbc:oracle:thin:#//HOST:PORT/SID", "user", "password");
dataSource.setSchema("MY_SCHEMA");
return dataSource;
}
}
And the corrected exapmle using a oracle.jdbc.pool.OracleDataSource:
#Config
#EnableTransactionManagement
public class appDataConfig {
/* Other Bean Defs */
#Bean
public DataSource dataSource() {
// configure and return the necessary JDBC DataSource
OracleDataSource datasource = null;
try {
datasource = new OracleDataSource();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
datasource.setURL("jdbc:oracle:thin:#//HOST:PORT/SID");
datasource.setUser("user");
datasource.setPassword("password");
return datasource;
}
}
I was having the same issue with mysql datasource using spring data that would work outside but gave me this error when deployed on tomcat.
The error went away when I added the driver jar mysql-connector-java-8.0.16.jar to the jres lib/ext folder
However I did not want to do this in production for fear of interfering with other applications. Explicity defining the driver class solved this issue for me
spring.datasource.driver-class-name: com.mysql.cj.jdbc.Driver
You will get this same error if there is not a Resource definition provided somewhere for your app -- most likely either in the central context.xml, or individual context file in conf/Catalina/localhost. And if using individual context files, beware that Tomcat freely deletes them anytime you remove/undeploy the corresponding .war file.
For me the same error occurred while connecting to postgres while creating a dataframe from table .It was caused due to,the missing dependency. jdbc dependency was not set .I was using maven for the build ,so added the required dependency to the pom file from maven dependency
jdbc dependency
For me adding below dependency to pom.xml file just solved like magic! I had no mysql connector dependency and even adding mssql jdbc jar file to build path did not work either.
<dependency>
<groupId>com.microsoft.sqlserver</groupId>
<artifactId>mssql-jdbc</artifactId>
<version>9.4.0.jre11</version>
</dependency>
In my case I was working on a Java project with Maven and encountered this error.
In your pom.xml file make sure you have this dependencies
<dependencies>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>8.0.11</version>
</dependency>
</dependencies>
and where you create connection have something like this
public Connection createConnection() {
try {
String url = "jdbc:mysql://localhost:3306/yourDatabaseName";
String username = "root"; //your my sql username here
String password = "1234"; //your mysql password here
Class.forName("com.mysql.cj.jdbc.Driver");
return DriverManager.getConnection(url, username, password);
} catch (SQLException | ClassNotFoundException e) {
e.printStackTrace();
}
return null;
}
faced same issue. in my case ':' colon before '//' (jdbc:mysql://localhost:3306/dbname) was missing, and it just fixed the problem.
make sure : and // are placed properly.
I ran into the same error. In my case, the JDBC URL was correct, but the issue was with classpath. However, adding MySQL connector's JAR file to the -classpath or -cp (or, in the case of an IDE, as a library) doesn't resolve the issue. So I will have to move the JAR file to the location of Java bytecode and run java -cp :mysql_connector.jar to make this work. If someone runs into the same issue as mine, I'm leaving this here.
I encountered this issue by putting a XML file into the src/main/resources wrongly, I deleted it and then all back to normal.

Where to put c3p0 dependency in Tomcat Container

I was under the impression that the libraries for both the database driver (postgres-x.x.jar'in my case) and the connection pooler (c3p0) had to reside in the container's lib (e.g. for Tomcat7, $CATALINA_HOME/lib).
However, the official C3p0 documentation doesn't provide any information with regards to put the connection pool's jar in the container vs having it in the application's war:
Place the files lib/c3p0-0.9.5.2.jar and lib/mchange-commons-java-0.2.11.jar somewhere in your CLASSPATH (or any other place where your application's classloader will find it). That's it!
A current issue in a new tomcat installation (java.lang.NoClassDefFoundError: com/mchange/v2/ser/Indirector, when I have the mchange-commons-java dependency in the application's WAR and the c3p0 dependency in $CATALINA_HOME/lib) made me revisit this, but I can't find any authoritative information regarding where to put these libraries.
Usual application configuration
In my case the c3p0 configuration is made via spring bean within the application's classpath:
<bean id="c3p0DataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
scope="singleton" destroy-method="close">
<property name="driverClass">
<value>org.postgresql.Driver</value>
</property>
<property name="jdbcUrl">
<value>${jdbc.url}</value>
</property>
<property name="user">
<value>${jdbc.user}</value>
</property>
<property name="password">
<value>${jdbc.pw}</value>
</property>
...
<bean>
If I have multiple applications in the same Tomcat container, each will have one c3p0 bean like this contained in its war.
Memory Leaks?
The assumption for having the postgres.jar and c3p0.jar in the container's lib/ and not in the war was that the latter would cause memory leaks.
Leak in Postgres Driver
This user states that JDBC drivers register themselves in the JVM-wide singleton DriverManager which is shared by all web apps. If you have the same (as in class name) JDBC driver register twice from two different web apps, this might cause your problem. This is even more problematic if your web apps use different versions of the same JDBC driver.
Leak in c3p0
We moved c3p0 to $CATALINA_HOME/lib after this comment on Stackoverflow (we had a similar warning when undeploying an application).
Should they reside in Tomcat or the application's lib/ ?
Whether or not you need to put a jar in Tomcat's lib directory depends on whether Tomcat needs to know about it or not. And that depends on how you are configuring things.
As a general rule, if you are mentioning a class in a Tomcat config file, then that class (and those that it depends on) must be in Tomcat's lib directory.
For example, if you configure your DataSource in Tomcat's config files, then you need to make your driver class available to Tomcat. If instead you configure your DataSource within your application's code then you do not.
You do not specify how you are configuring C3P0, so we cannot tell you where the jar needs to be. Of course, if Tomcat needs it and it is not there, then you should expect to see an exception logged and things won't work properly.

activemq jndi tomcat error

I am trying to use ActiveMQ via JNDI, deploying the application in Tomcat 7.0 server.
I have made the settings for ActiveMQ connection factory and queue in Tomcat context.xml configuration file, and they look like this:
<Resource
auth="Container"
brokerName="LocalActiveMQBroker"
brokerURL="vm://localhost"
clientID="TomcatClientID"
description="JMS Connection Factory"
factory="org.apache.activemq.jndi.JNDIReferenceFactory"
name="jms/ConnectionFactory"
password="password"
type="org.apache.activemq.ActiveMQConnectionFactory"
userName="user"/>
<Resource
auth="Container"
description="Order Queue"
factory="org.apache.activemq.jndi.JNDIReferenceFactory"
name="jms/orderQ"
physicalName="orderQ"
type="org.apache.activemq.command.ActiveMQQueue"/>
and I try to get the connection factory this way:
nnectionFactory connectionFactory = (ConnectionFactory) context
.lookup("java:comp/env/jms/ConnectionFactory");
but I get an exception:
java.lang.NoClassDefFoundError: org/slf4j/impl/StaticLoggerBinder
org.slf4j.LoggerFactory.getSingleton(LoggerFactory.java:230)
I tried to find out the cause of the exception, but I found only that it could come from commons-logging jar, which I have added to tomcat lib folder.
Where am I wrong?
commons-logging is a library that has to do with logging indeed, but it's from Apache. Also slf4j is just a facade, you need to provide an actual implementation for slf4j. I would suggest logback, which is a "better" way to do logging in java. So you are going to need 3 jars on your classpath: slf4j-api.jar, logback-core.jar and logback-classic.jar.
If on the other hand you do not want to use logback then any other implementation will work.

how to disable tomcat caching?

how to disable tomcat caching?
I use this -
<Context antiJARLocking="true" antiResourceLocking="true" cachingAllowed="false" cacheMaxSize ="0" cacheTTL="1">
in Tomcat/conf/context.xml
but it not helps
Actual problem is antiResourceLocking="true".
Looks like there is a conflict with cachingAllowed="false".
I'm not sure what you're using, but in context.xml you can change the value of cachingAllowed by removing the flag.
Remember to delete the cache folder after that.
Resources :
Apache Tomcat Configuration Reference
On the same topic :
How do I disable tomcat caching? I'm having weird static file problems.
cachingAllowed did not help. I resolved this by modifying :
$CATALINA_HOME/conf/Catalina/localhost/thewebapp.xml
which is the cached file of context.xml
Put below code in your sever.xml file.
<Context className="org.apache.catalina.core.StandardContext"
cachingAllowed="false"
charsetMapperClass="org.apache.catalina.util.CharsetMapper"
cookies="true"
reloadable="false"
wrapperClass="org.apache.catalina.core.StandardWrapper">
</Context>
Make sure to delete all data from /work/Catalina/localhost directory before restarting tomcat.
Also clear your browser cache.
Its a good practice to disable browser caching while your app is in development.
This post may help Disabling Chrome cache for website development

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