Name java:comp is not bound in this Context javax.naming.NameNotFoundException - java

This is my code:
Context ctx = new InitialContext();
Context envCtx = (Context)ctx.lookup("java:comp/env");
It usually works fine, but sometimes it throws this error:
Name java:comp is not bound in this Context
javax.naming.NameNotFoundException: Name java:comp is not bound in this Context
at org.apache.naming.NamingContext.lookup(NamingContext.java:770)
at org.apache.naming.NamingContext.lookup(NamingContext.java:153)
at javax.naming.InitialContext.lookup(Unknown Source)
This is my context.xml:
<!-- Default set of monitored resources -->
<WatchedResource>WEB-INF/web.xml</WatchedResource>
<Environment name="fileLocation" value="dev" type="java.lang.String" override="false"/>
<Environment name="log4JFileLocation" override="false" type="java.lang.String" value="dev"/>
Any ideas of what is going on?
Thanks :)

Related

javax.naming.NameNotFoundException: While trying to look up comp/env/UserTransaction

While deploying my application on weblogic 12 I am facing following exception
weblogic.application.ModuleException:
javax.naming.NameNotFoundException: While trying to look up
comp/env/UserTransaction in /app/webapp/Demo-UNCONTROLLED
ARTIFACT.war/895045661.; remaining name 'comp/env/UserTransaction'
My spring-jpa.xml is as follows
<jee:jndi-lookup id="userTransaction" jndi-name="java:comp/env/UserTransaction" resource-ref="true" cache="true"/>
context.xml is as follows
<?xml version="1.0" encoding="UTF-8"?>
<Context path="/private/tool" sessionCookieName="JSESSIONID_TOOL" disableURLRewriting="true">
<Resource name="UserTransaction" auth="Container" type="javax.transaction.UserTransaction" factory="org.objectweb.jotm.UserTransactionFactory" jotm.timeout="60"/>
</Context>
How to configure UserTransaction in weblogic? Why my application is failing to lookup comp/env/UserTransaction ?

Tomcat 8.5.4 javax.naming.NameNotFoundException

I am developing a web application with Tomcat 8.5.4. I'm using a properties configured as Resource. So, my $TOMCAT_HOME/conf/server.xml contains
<GlobalNamingResources>
<Resource name="properties/global" auth="Container" type="java.util.Properties" />
</GlobalNamingResources>
The META-INF/context.xml of my webapp has
<Context antiResourceLocking="true" path="/mywebapp">
<ResourceLink global="properties/global" name="properties/global" type="java.util.Properties"/>
</Context>
I'm looking up the resource as follow
Context initContext = new InitialContext();
Context envContext = (Context) initContext.lookup("java:/comp/env");
(Properties) envContext.lookup("properties/global");
However, I'm getting the exception
javax.naming.NameNotFoundException: Name [properties/global] is not bound in this Context. Unable to find [properties].
What's wrong? Thanks.

Externalize properties in Tomcat

I would like to configure a series of environment-dependant settings as an external resource, so that the same WAR artifact can be configured in any application server.
In Glassfish I rememeber that I just created a .properties file using the built-in Properties Resource JNDI Factory, and it worked like a charm, but there's no such thing in Tomcat.
I tried defining a java.net.URL and a java.lang.String to define just the path that this file is held in, but I get the following error:
Caused by: java.io.FileNotFoundException: Could not open ServletContext resource [/c://app.properties]
So what would be a good way to create an environment-agnostic set of properties for my application?
PS: this is how I define my properties in Spring:
<jee:jndi-lookup id="appProperties" jndi-name="java:comp/env/url/urlAppProperties" />
<bean id="application-properties" class="org.springframework.beans.factory.config.PropertiesFactoryBean">
<property name="locations">
<list>
<value>#{ appProperties }</value>
</list>
</property>
</bean>
You can add external configuration values to the JNDI context using Tomcat's resource configuration elements. As described in the Tomcat documentation, you can define a <GlobalNamingResources> element in your server.xml listing a set of configuration values which are available to all contexts (web applications) on that server:
Example taken from the Tomcat docs:
<GlobalNamingResources ...>
...
<Environment name="maxExemptions" value="10"
type="java.lang.Integer" override="false"/>
...
</GlobalNamingResources>
These environment variables are then available via JDNI in the java:comp/env context. In order to use such variables in a web application, you have to link to them in the individual context.xml configuration files using the <ResourceLink> element.
<Context>
<ResourceLink name="maxExemptions" global="maxExemptions" type="java.lang.Integer"/>
</Context>
With this set up, you can access these values through the standard JNDI API.

Should you set up database connection properties in server.xml or context.xml

I am trying to set up the database connection properties using JNDI for a Spring web application.
I am considering two approaches as below:
Approach 1:
In your Spring configuration you may have something like:
<jee:jndi-lookup id="dataSource" jndi-name="java:comp/env/jdbc/facs"/>
Then in your webapp /META-INF/context.xml file you should have something similar too:
<?xml version='1.0' encoding='utf-8'?>
<!-- antiResourceLocking="true" -->
<Context path="/podd-apn"
reloadable="true"
cachingAllowed="false"
antiResourceLocking="true"
>
<Resource name="jdbc/facs"
type="javax.sql.DataSource" username="${database.username}" password="${database.password}"
driverClassName="org.postgresql.Driver"
url="${database.url}"
maxActive="8" maxIdle="4"
global="jdbc/facs"
/>
</Context>
And in your web.xml you should something like:
<!-- JNDI -->
<resource-ref>
<description>FACs Datasource</description>
<res-ref-name>jdbc/facs</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
Approach 2:
Setup in the Spring context like this:
<jee:jndi-lookup id="dbDataSource"
jndi-name="jdbc/DatabaseName"
expected-type="javax.sql.DataSource" />
You can declare the JNDI resource in Tomcat's server.xml using something like this:
<GlobalNamingResources>
<Resource name="jdbc/DatabaseName" auth="Container" type="javax.sql.DataSource"
username="dbUsername" password="dbPasswd"
url="jdbc:postgresql://localhost/dbname"
driverClassName="org.postgresql.Driver"
initialSize="5" maxWait="5000"
maxActive="120" maxIdle="5"
validationQuery="select 1"
poolPreparedStatements="true"/>
</GlobalNamingResources/>
And reference the JNDI resource from Tomcat's web context.xml like this:
<ResourceLink name="jdbc/DatabaseName"
global="jdbc/DatabaseName"
type="javax.sql.DataSource"/>
My question is where is the best place to keep database properties? Should they be placed in server.xml or context.xml?
Also, if I have 2 databases, should I use two configs?
Also, is it best practice to directly place them in either server.xml or context.xml? Or do I need to configure through Tomcat Manager GUI console?
Thanks!
I prefer a third approach that takes the best from
Approach 1 and Approach 2 described by user1016403.
Approach 3
Save database properties on the server.xml
reference the server.xml database properties from the web application META-INF/context.xml
Approach 3 benefits
While the first point is useful for security reasons the second point is useful for referencing server properties value from the web application, even if server properties values will change.
Moreover decoupling resource definitions on the server from their use by the web application makes such configuration scalable across organizations with various complexity where different teams work on different tiers/layers: the server administrators team can work without conflicting with developers team if the administrator shares the same JNDI name with the developer for each resource.
Approach 3 implementation
Define the JNDI name jdbc/ApplicationContext_DatabaseName.
Declare the jdbc/ApplicationContext_DatabaseName's various properties and values in Tomcat's server.xml using something like this:
<GlobalNamingResources>
<Resource name="jdbc/ApplicationContext_DatabaseName" auth="Container" type="javax.sql.DataSource"
username="dbUsername" password="dbPasswd"
url="jdbc:postgresql://localhost/dbname"
driverClassName="org.postgresql.Driver"
initialSize="5" maxWait="5000"
maxActive="120" maxIdle="5"
validationQuery="select 1"
poolPreparedStatements="true"/>
</GlobalNamingResources/>
Link the jdbc/ApplicationContext_DatabaseName's properties from web application META-INF/context.xml by an application-private JNDI context java:comp/env/ specified in the name attribute:
<Context path="/ApplicationContext" ... >
<!--
"global" attribute links to GlobalNamingResources in the ${catalina.base}/conf/server.xml (server administrator team)
"name" attribute is relative to the application-private JNDI context java:comp/env/ and is looked up from the java web application (application developer team)
-->
<ResourceLink global="jdbc/ApplicationContext_DatabaseName" name="jdbc/DatabaseName" type="javax.sql.DataSource"/>
</Context>
Finally, in order to use the JNDI resource, specify the JNDI name jdbc/DatabaseName in web application's deployment descriptor:
<resource-ref>
<description>DatabaseName's Datasource</description>
<res-ref-name>jdbc/DatabaseName</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
and in Spring context:
<jee:jndi-lookup id="DatabaseNameDataSource"
jndi-name="jdbc/DatabaseName"
expected-type="javax.sql.DataSource" />
Approach 3 drawbacks
If the JNDI name gets changed then both the server.xml and the META-INF/context.xml will have to be edited and a deploy would be necessary; nevertheless this scenario is rare.
Approach 3 variations
Many data sources used by one web application
Simply add configurations to Tomcat's server.xml:
<GlobalNamingResources>
<Resource name="jdbc/ApplicationContext_DatabaseName1" ... />
<Resource name="jdbc/ApplicationContext_DatabaseName2" ... />
...
</GlobalNamingResources/>
Add link web application META-INF/context.xml by an application-private JNDI context java:comp/env/ specified in the name attribute:
<Context path="/ApplicationContext" ... >
<ResourceLink global="jdbc/ApplicationContext_DatabaseName1" name="jdbc/DatabaseName1" ... />
<ResourceLink global="jdbc/ApplicationContext_DatabaseName2" name="jdbc/DatabaseName2" ... />
...
</Context>
Finally add JNDI resources usage in web application's deployment descriptor:
<resource-ref>
<description>DatabaseName1's Datasource</description>
<res-ref-name>jdbc/DatabaseName1</res-ref-name> ...
</resource-ref>
<resource-ref>
<description>DatabaseName2's Datasource</description>
<res-ref-name>jdbc/DatabaseName2</res-ref-name> ...
</resource-ref>
...
and in Spring context:
<jee:jndi-lookup id="DatabaseName1DataSource"
jndi-name="jdbc/DatabaseName1" ... />
<jee:jndi-lookup id="DatabaseName2DataSource"
jndi-name="jdbc/DatabaseName2" ... />
...
Many data sources used by many web application on the same server
Simply add configuration to Tomcat's server.xml:
<GlobalNamingResources>
<Resource name="jdbc/ApplicationContextX_DatabaseName1" ... />
<Resource name="jdbc/ApplicationContextX_DatabaseName2" ... />
<Resource name="jdbc/ApplicationContextY_DatabaseName1" ... />
<Resource name="jdbc/ApplicationContextY_DatabaseName2" ... />
...
</GlobalNamingResources/>
the others configuration should be deducible from previous variation case.
Many data sources to the same database used by many web application on the same server
In such case a Tomcat's server.xml configurations like:
<GlobalNamingResources>
<Resource name="jdbc/ApplicationContextX_DatabaseName" ... />
<Resource name="jdbc/ApplicationContextY_DatabaseName" ... />
ends up in two different web applications META-INF/context.xml like:
<Context path="/ApplicationContextX" ... >
<ResourceLink global="jdbc/ApplicationContextX_DatabaseName" name="jdbc/DatabaseName" ... />
</Context>
and like:
<Context path="/ApplicationContextY" ... >
<ResourceLink global="jdbc/ApplicationContextY_DatabaseName" name="jdbc/DatabaseName" ... />
</Context>
so someone might be worried about the fact that the same name="jdbc/DatabaseName" is looked up, and then used, by two different applications deployed on the same server: this is not a problem because the jdbc/DatabaseName is an application-private JNDI context java:comp/env/, so ApplicationContextX by using java:comp/env/ can't (by design) look up the resource linked to global="jdbc/ApplicationContextY_DatabaseName".
Of course if you felt more relaxed without this worry you might use a different naming strategy like:
<Context path="/ApplicationContextX" ... >
<ResourceLink global="jdbc/ApplicationContextX_DatabaseName" name="jdbc/applicationXprivateDatabaseName" ... />
</Context>
and like:
<Context path="/ApplicationContextY" ... >
<ResourceLink global="jdbc/ApplicationContextY_DatabaseName" name="jdbc/applicationYprivateDatabaseName" ... />
</Context>
YOUR_APP.xml file
I prefer Approach 2 (put everything (not only some attribute in the config), but instead of placing them in the global server.xml or global context.xml you should place it in the application-specific context.xml.default YOUR_APP.xml file in your Tomcat.
The YOUR_APP.xml file is located in $catalinaHome/conf/<engine>/<host> (for example conf/Catalina/localhost/YOUR_APP.xml).
The configuration in application specific YOUR_APP.xml is only available for the specific application.
See the guide published by MuleSoft. And see the official documentation, Tomcat Configuration Reference, page for The Context Container
Version 9
Version 8
To quote that documentation:
Individual Context elements may be explicitly defined:
• …
• In individual files (with a ".xml" extension) in the $CATALINA_BASE/conf/[enginename]/[hostname]/ directory. The context path and version will be derived from the base name of the file (the file name less the .xml extension).
• …
Approach 4
Instead of using JNDI I work with .properties files and build complex object during program initialization instead on configuration time.
You already use Spring and it is easy construct DataSource by:
<context:property-placeholder location="classpath:app.properties"/>
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
<property name="driverClassName" value="oracle.jdbc.OracleDriver"/>
<property name="url" value="jdbc:oracle:thin:#${db.host}:${db.port}:${db.user}"/>
<property name="username" value="${db.user}"/>
<property name="password" value="${db.pass}"/>
</bean>
I completely agree with Ralph with using deployment descriptor in $CATALINA_BASE/conf/[enginename]/[hostname]/$APP.xmlbut instead JNDI I like plain key-value file!
With Spring injecting above properties into bean fields are easy:
#Value("${db.user}") String defaultSchema;
instead of JNDI:
#Inject ApplicationContext context;
Enviroment env = context.getEnvironment();
String defaultSchema = env.getProperty("db.user");
Note also that EL allow this (default values and deep recursive substitution):
#Value('${db.user:testdb}') private String dbUserName;
<property name='username' value='${db.user.${env}}'/>
To externalize .properties file I use modern Tomcat 7 that has org.apache.catalina.loader.VirtualWebappLoader:
<Loader className="org.apache.catalina.loader.VirtualWebappLoader"
virtualClasspath="/srv/web/app/"/>
So your devops fill virtualClasspath with local external full paths which is separate per application and put local app.propertiesto that dir.
See also:
Adding a directory to tomcat classpath
Can I create a custom classpath on a per application basis in Tomcat
Externalizing Tomcat webapp config from .war file
How to read a properties file outside my webapp context in Tomcat
Configure Tomcat to use properties file to load DB connection information
Externalize Tomcat configuration
step 1: context.xml
<Context path="/projectname">
<Resource auth="Container"
driverClassName="com.mysql.jdbc.Driver"
logAbandoned="true"
maxActive="100" ``
maxIdle="30"
maxWait="10000"
name="refname"
removeAbandoned="true"
removeAbandonedTimeout="60"
type="javax.sql.DataSource"
url="jdbc:mysql://localhost:8080/dbname"
username="root"
password="root"/>
</Context>
Step 2 : web.xml
<resource-ref>
<description>DB Connection</description>
<res-ref-name>refname</res-ref-name>
<res-type>javax.sql.DataSource</res-type>
<res-auth>Container</res-auth>
</resource-ref>
Step 3 : create a class to get connection
Connection connection = null;
Context context = (Context) new InitialContext().lookup("java:comp/env");
DataSource ds = (DataSource) context.lookup("refname");
connection = ds.getConnection();
Everything is set
You also can use JNDI URL support for different application configuration for test, integration test, production.
<Context>
...
<Resource auth="Container" factory="com.benasmussen.jndi.url.URLFactory"
name="url/MyUrl" type="java.net.URL" url="file:///your/path/to/file"/>
...
</Context>
<jee:jndi-lookup id="myUrl" jndi-name="java:comp/env/url/MyUrl" expected-type="java.net.URL" />
Check out the GitHub project Tomcat JNDI URL Support to enable JNDI URL support for Tomcat servers.

Getting DataSource resource in a Java web app

I have the following resource tag in my context.xml file:
<?xml version="1.0" encoding="UTF-8"?>
<Context antiJARLocking="true" path="/myApp">
<Resource name="jdbc/myDS" auth="Container"
type="javax.sql.DataSource" maxActive="100" maxIdle="30" maxWait="1000"
username="user" password="passwd"
driverClassName="com.mysql.jdbc.Driver"
url="jdbc:mysql://localhost:3306/myDB" />
</Context>
I am developing a Java web app using the Stripes framework in NetBeans.
How can I get this resource from within a Java class?
You need your bean to be instantiated by something (a dependecy injection framework) which knows how to handle the #Resrouce annotation. JSP itself doesn't know how.
In this case it would be simpler to locate the DataSource in the JNDI context:
Context initContext = new InitialContext();
Context envContext = (Context) initContext.lookup("java:/comp/env");
DataSource ds = (DataSource) envContext.lookup("jdbc/myDS");
Thank you Bozho for the answer. I only had to change the lookup string to get it to work:
Context ctx = new InitialContext();
DataSource ds = (DataSource) ctx.lookup("java:comp/env/jdbc/myDS");
Connection conn = ds.getConnection();

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