Install WebLogic 12.2.1.3 on CentOS 7 without GUI

1. You need have a CentOS 7 mini machine / virtual machine

I'm using virtual box and installed CentOS 7 Mini.

2. Install JDK1.8 and add in $PATH

WebLogic 12.2.1.3 need JDK 1.8 and above.
Edit ~/.bash_profile after unzip jdk-8u144-linux-x64.tar.gz into /opt.

JAVA_HOME=/opt/jdk1.8.0_144

export JAVA_HOME

PATH=$PATH:$HOME/.local/bin:$HOME/bin:$JAVA_HOME/bin

export PATH

3. Install WebLogic 12.2.1.3 in silent mode

a. Create directory /opt/Oracle for weblogic, change the own to installation account.

My installation account names developer, and it's in developer group.

b. Create response file, /opt/Oracle/wls12213.rsp

[ENGINE]

#DO NOT CHANGE THIS.

Response File Version=1.0.0.0.0

[GENERIC]

#Set this to true if you wish to skip software updates

DECLINE_AUTO_UPDATES=true

#My Oracle Support User Name

MOS_USERNAME=

#My Oracle Support Password

MOS_PASSWORD=

#If the Software updates are already downloaded and available on your local system, then specify the path to the directory where these patches are available and set SPECIFY_DOWNLOAD_LOCATION to true

AUTO_UPDATES_LOCATION=

#Proxy Server Name to connect to My Oracle Support

SOFTWARE_UPDATES_PROXY_SERVER=

#Proxy Server Port

SOFTWARE_UPDATES_PROXY_PORT=

#Proxy Server Username

SOFTWARE_UPDATES_PROXY_USER=

#Proxy Server Password

SOFTWARE_UPDATES_PROXY_PASSWORD=

#The oracle home location. This can be an existing Oracle Home or a new Oracle Home

ORACLE_HOME=/opt/Oracle/wls12213

#The federated oracle home locations. This should be an existing Oracle Home. Multiple values can be provided as comma seperated values

FEDERATED_ORACLE_HOMES=

#Set this variable value to the Installation Type selected. e.g. WebLogic Server, Coherence, Complete with Examples.

INSTALL_TYPE=Complete with Examples

ORACLE_HOME and INSTALL_TYPE are critical items. Their descriptions are above them respectively.

b. Create oracle inventory file /opt/Oracle/oraInst.loc

inventory_loc=/opt/Oracle/oraInventory

inst_group=developer

The installation account must have write privilege on directory /opt/Oracle/oraInventory.
developer is the group name of your installation account.

c. Run installer in silent mode

Copy fmw_12.2.1.3.0_wls.jar into /opt/Oracle.
Run installer,

[developer@CentOS7Mini Oracle]$ cd /opt/Oracle/

[developer@CentOS7Mini Oracle]$ java -jar fmw_12.2.1.3.0_wls.jar -silent -responseFile /opt/Oracle/wls12213.rsp -invPtrLoc /opt/Oracle/oraInst.loc

4. Create domain with WLST

WLST - WebLogic Scripting Tool, which is installed with weblogic.

a. Start wlst

[developer@CentOS7Mini Oracle]$ cd /opt/Oracle/wls12213/oracle_common/common/bin/

[developer@CentOS7Mini bin]$ ./wlst.sh 

b. Domain creation commands

I created a "Base WebLogic Server Domain" with template, wls.jar. All templates are in  /opt/Oracle/wls12213/wlserver/common/templates/wls. You can unzip them to see some detailed descriptions.

readTemplate('/opt/Oracle/wls12213/wlserver/common/templates/wls/wls.jar')
WARNING: The readTemplate is deprecated. Use selectTemplate followed by loadTemplates in place of readTemplate.


# Set the listen address and listen port for the Administration Server
cd("Servers/AdminServer")
set("ListenAddress","")
set("ListenPort",7001)

# Enable SSL on the Administration Server and set the SSL listen address and
# port
create("AdminServer","SSL")
cd("SSL/AdminServer")
set("Enabled","True")
set("ListenPort",7002)

# Set the domain password for the WebLogic Server administration user
cd("/")
cd("Security/base_domain/User/weblogic")
cmo.setPassword("dev123")

# If the domain already exists, overwrite the domain
setOption("OverwriteDomain","true")

# write the domain and close the template
writeDomain("/opt/Oracle/wls12213/user_projects/domains/base_domain")
closeTemplate()

exit()

5. Start WebLogic

a. Start nodemanager

If you just want to use the nodemanager to manage the domain which you just created you don't need to do any additional configurations, and just use the script startNodemanager.sh

under /opt/Oracle/wls12213/user_projects/domains/base_domain/bin.

cd /opt/Oracle/wls12213/user_projects/domains/base_domain/bin

nohup ./startNodeManager.sh &

b. Start Administration Server

cd /opt/Oracle/wls12213/user_projects/domains/base_domain/bin

nohup ./starWebLogic.sh &

c. Login WebLogic Administration Console

• Create machine  
• Create cluster 
• Create manager servers

Reference:

Using the Oracle Universal Installer in Silent Mode

Creating WebLogic Domains Using WLST Offline

WebLogic 12c node manager startup issue: weblogic.nodemanager.common.ConfigException: Native version is enabled but NodeManager native library could not be loaded

I got this issue when I was starting nodemanager on mac, OS x.

Sep 06, 2017 9:47:27 PM weblogic.nodemanager.server.NMServer writeProcessId

WARNING: NodeManager native library could not be loaded to write process id

java.lang.UnsatisfiedLinkError: no nodemanager in java.library.path

at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1867)

at java.lang.Runtime.loadLibrary0(Runtime.java:870)

at java.lang.System.loadLibrary(System.java:1122)

at weblogic.nodemanager.util.UnixProcessControl.<init>(UnixProcessControl.java:25)

at weblogic.nodemanager.util.ProcessControlFactory.getProcessControl(ProcessControlFactory.java:23)

at weblogic.nodemanager.server.NMServer.writeProcessId(NMServer.java:288)

at weblogic.nodemanager.server.NMServer.writePidFile(NMServer.java:264)

at weblogic.nodemanager.server.NMServer.<init>(NMServer.java:154)

at weblogic.nodemanager.server.NMServer.getInstance(NMServer.java:134)

at weblogic.nodemanager.server.NMServer.main(NMServer.java:589)

at weblogic.NodeManager.main(NodeManager.java:31)

<6 Sep, 2017 9:47:27 PM SGT> <SEVERE> <Fatal error in NodeManager server>

weblogic.nodemanager.common.ConfigException: Native version is enabled but NodeManager native library could not be loaded

at weblogic.nodemanager.server.NMServerConfig.initProcessControl(NMServerConfig.java:627)

at weblogic.nodemanager.server.NMServerConfig.<init>(NMServerConfig.java:392)

at weblogic.nodemanager.server.NMServer.<init>(NMServer.java:156)

at weblogic.nodemanager.server.NMServer.getInstance(NMServer.java:134)

at weblogic.nodemanager.server.NMServer.main(NMServer.java:589)

at weblogic.NodeManager.main(NodeManager.java:31)

Caused by: java.lang.UnsatisfiedLinkError: no nodemanager in java.library.path

at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1867)

at java.lang.Runtime.loadLibrary0(Runtime.java:870)

at java.lang.System.loadLibrary(System.java:1122)

at weblogic.nodemanager.util.UnixProcessControl.<init>(UnixProcessControl.java:25)

at weblogic.nodemanager.util.ProcessControlFactory.getProcessControl(ProcessControlFactory.java:23)

at weblogic.nodemanager.server.NMServerConfig.initProcessControl(NMServerConfig.java:625) 

Because node manager looks for NodeManager native library but can't find it.

Edit nodemanager.properties and set 

NativeVersionEnabled=true

EJB naming conventions

How does Oracle official JEE 7 tutorial say?

Items	Syntax	Example
EJB bean name	nameBean	HelloBean
EJB bean java class name	nameBean	HelloBean
Business interface	name	Hello

How is Java SE API doing?

Interface Name	Implementation Class Name
java.util.List<E>	AbstractList AbstractSequentialList ArrayList AttributeList LinkedList
java.util.Map<K,V>	AbstractMap Attributes AuthProvider ConcurrentHashMap ConcurrentSkipListMap EnumMap HashMap Hashtable IdentityHashMap LinkedHashMap Properties TreeMap

There is a lot examples in java api. Some abstract classes' name and their implementation classes are all named very well. Anyway, I never see something like IList, ListInter or ListInterface ......

How do you name your interface and enterprise session bean? 

Implement an Enterprise Session Bean

This post complies JEE 7, and test in weblogic 12c2.

How does container know a class is Session Bean?

The container regards a class as enterprise session bean if this class is annotated with either @Stateless, @Stateful or @Singleton annotation and no matter it's annotated with @Local, @Remote or @LocalBean annotation or it implements any interface which is annotated with @Local or @Remote annotation.
Now we know the key to make class an EJB is to annotate it with @Stateless, @Stateful or @Singleton regardless it has business interface or not.
There 2 styles of session bean, one is having business interface, another one is no-interface.
Clients access enterprise beans either through a no-interface view or through a business interface. A no-interface view of an enterprise bean exposes the public methods of the enterprise bean implementation class to clients.
Session beans can have more than one business interface. Session beans should, but are
not required to, implement their business interface or interfaces.

The ways to create EJB

We always take Local Stateless EJB as examples in below sections. 

1. Implement an interface which is annotated with @Local or @Remote

public interface Hello {

    void say(String msg);

}

/* Most of time in practice we also create a RemoteHello interface and implementation class implements these 2 interfaces meanwhile to let this bean have remote and local bean characters at the same time.*/

@Local

public interface LocalHello extends Hello{

    

}

/* EJB */

@Stateless(name="ejb/LocalHelloBean")

public class LocalHelloBean implements LocalHello{

    @Override

    public void say(String msg) {

        ...

    }

    

}

LocalHelloBean is a local ejb and has business interface LocalHello .

2. Annotate class with @Local or @Remote

public interface Hello {
    void say(String msg);
}

/* EJB */
@Local(com.nwb.jpractice.jee7.helloworld.ejb.api.Hello.class)
@Stateless(name="ejb/HelloBean")
public class HelloBean implements Hello{

    @Override
    public void say(String msg) {
        ...
    }
 
}

HelloBean is local ejb and has business interface Hello.

3. Annotate class with @LocalBean

No interface local view EJB

@LocalBean
@Stateless(name="ejb/LocalBeanAnnotatedHelloBean")
public class LocalBeanAnnotatedHelloBean {
 
    public void say(String msg) {
        ...
    }
 
}

LocalBeanAnnotatedHelloBean is a local ejb and has no-interface view.

4. No @Local, @Remote or @LocalBean annotation and implement an interface without @Local or @Remote annotation

This is the most magical case.

public interface Hello {
    void say(String msg);
}

@Stateless(name="ejb/NoLocalAnnotatedHelloBean")
public class NoLocalAnnotatedHelloBean implements Hello{
 
    public void say(String msg) {
        ...
    }
 
}

Interface Hello is not annotated with Local or Remove but container will automatically regard it as business interface. So NoLocalAnnotatedHelloBean is a local ejb and business interface Hello.

5. No @Local, @Remote or @LocalBean annotation and No implement any interface

@Stateless(name="ejb/NoLocalAnnotationNoInterfaceHelloBean")
public class NoLocalAnnotationNoInterfaceHelloBean {
 
    public void say(String msg) {
        ...
    }
 
}

NoLocalAnnotationNoInterfaceHelloBean is local ejb and has no-interface view. This case is completely as same as @LocalBean case at section 3.

Now we have been able to create our own session bean. After we have some beans how do we get the reference of the ejb?

Create Java EE Maven Project

Project structures

Illustrate how to create Java EE application project with maven. The whole application has one parent pom, 1 web module, 1 ejb module, 1 normal java module and 1 ear assembly project to package former those modules together.
Final structures should be like below,

+helloworld
 |----helloworld-ear
 |----helloworld-war
 |----helloworld-ejb-local
 |----helloworld-ejb-api
 |----pom.xml

maven commands

Run following maven commands,

cd <baseDir>
mvn archetype:generate -B -DarchetypeGroupId=org.codehaus.mojo.archetypes -DarchetypeArtifactId=pom-root -DarchetypeVersion=1.1 -DgroupId=com.nwb.jpractice.jee7 -DartifactId=helloworld -Dversion=1.0-SNAPSHOT

cd <baseDir>/helloworld
mvn archetype:generate -B -DarchetypeGroupId=org.apache.maven.archetypes -DarchetypeArtifactId=maven-archetype-quickstart -DarchetypeVersion=1.1 -DgroupId=com.nwb.jpractice.jee7 -DartifactId=helloworld-ejb-api -Dversion=1.0-SNAPSHOT

mvn archetype:generate -B -DarchetypeGroupId=org.codehaus.mojo.archetypes -DarchetypeArtifactId=ejb-javaee7 -DgroupId=com.nwb.jpractice.jee7 -DartifactId=helloworld-ejb-local -Dversion=1.0-SNAPSHOT

mvn archetype:generate -B -DarchetypeGroupId=org.codehaus.mojo.archetypes -DarchetypeArtifactId=webapp-javaee7 -DgroupId=com.nwb.jpractice.jee7 -DartifactId=helloworld-war -Dversion=1.0-SNAPSHOT

mvn archetype:generate -B -DarchetypeGroupId=org.codehaus.mojo.archetypes -DarchetypeArtifactId=ear-javaee7 -DgroupId=com.nwb.jpractice.jee7 -DartifactId=helloworld-ear -Dversion=1.0-SNAPSHOT

Optimise pom and deployment descriptor

After that manually optimise some the pom and jee deployment descriptors.

Parent pom

• Specify encoding UTF-8
• Specify source code java version
• Specify which jvm version the compiled class compatible

    <properties>

        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>

        <maven.compiler.source>1.8</maven.compiler.source>

        <maven.compiler.target>1.8</maven.compiler.target>

    </properties> 

EAR Pom

Configure maven-ear-plugin

• Specify assembled modules [1]
• Customize module filename [2]. You may want to simply helloworld-ejb-local-1.0-SNAPSHOT.jar to helloworld-ejb-local.jar.
• Adopt skinny wars [3]. Libraries should have been in WEB-INF/lib are copied to EAR's lib and shared within whole application to shrink the size of war.
• Specify context-root for web module [4]. The context-root will be written into META-INF/application.xml. You don't have to create application.xml manually maven ear plugin is able to generate it when building project.

    <build>
        <finalName>${project.artifactId}</finalName>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.1</version>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-ear-plugin</artifactId>
                <version>2.8</version>
                <configuration>
                    <defaultLibBundleDir>lib</defaultLibBundleDir><!-- libraries of this application, this path is written into each META-INF/MANIFEST.MF during build-->
                    <skinnyWars>true</skinnyWars><!-- [3]-->
                    <modules>
                        <ejbModule><!-- [1] ejb module-->
                            <groupId>com.nwb.jpractice.jee7</groupId>
                            <artifactId>helloworld-ejb-local</artifactId>
                            <bundleFileName>helloworld-ejb-local.jar</bundleFileName><!-- [2]-->
                        </ejbModule>
                        <webModule><!-- [1] war module-->
                            <groupId>com.nwb.jpractice.jee7</groupId>
                            <artifactId>helloworld-war</artifactId>
                            <bundleFileName>helloworld-web.war</bundleFileName><!-- [2]-->
                        </webModule>
                    </modules>
                </configuration>
            </plugin>
        </plugins>
    </build>
 
    <dependencies>
        <dependency>
            <groupId>com.nwb.jpractice.jee7</groupId>
            <artifactId>helloworld-war</artifactId>
            <version>1.0-SNAPSHOT</version>
            <type>war</type>
        </dependency>
        <dependency>
            <groupId>org.nwb.jpractice.jee7</groupId>
            <artifactId>helloworld-ejb-local</artifactId>
            <version>1.0-SNAPSHOT</version>
            <type>ejb</type>
        </dependency>
        <!-- helloworld-ejb-api and other dependencies will be in ear's lib folder -->
        <dependency>
            <groupId>com.nwb.jpractice.jee7</groupId>
            <artifactId>helloworld-ejb-api</artifactId>
            <version>1.0-SNAPSHOT</version>
            <type>jar</type>
        </dependency>
    </dependencies>

Now this application can work, you can start building it and deploy it to weblogic.

Java EE application maven project and package

Package structure of JEE application

Typically a Java EE application is designed to have multiple modules or layers. Nowadays we often divide a general web application into 3 tiers, presentation, business logic, and persistence. Most of the time we directly split whole application into 3 modules according to this 3-tiers architecture thought.
From Java EE technology perspective presentation tier is a web module, and business tier (ejb3) and persistence tier (jpa) are both ejb modules. The whole application is the assembly of these web and ejb modules.
From deployment perspective a Java EE application is a .ear package (Enterprise Application aRchive), web module is .war package (Web Application aRchive), and ejb module is .jar package. .war and .jar are all packaged inside .ear.
Java EE module types

Package types	Structure	Description
EAR(.ear)	META-INF/application.xml lib/*.jar <web-module>.war <ejb-module>.jar ...	An enterprise application. It may contains several web and ejb modules. application.xml is Java EE standard deployment descriptor of EAR. Sometimes Java EE container specific application deployment descriptor is also in META-INF, for example, weblogic-application.xml is weblogic-specific deployment descriptor. lib contains shared libraries.
EJB(.jar)	META-INF/ejb-jar.xml *.class	An EJB module. ejb-jar.xml is EJB standard deployment descriptor. It has been optional since JEE5 introduced equivalent annotations. There may be also container-specific deployment descriptor under META-INF folder.
WAR(.war)	WEB-INF/web.xml WEB-INF/classes/*.class WEB-INF/lib/*.jar *.jsp *.js *.css *.html	An WEB module. web.xml is WEB application standard deployment descriptor. It has been optional since JEE5 introduced equivalent annotations. There may be also container-specific deployment descriptor under WEB-INF folder, for example, weblogic.xml for weblogic.

Maven projects of JEE application 

Now I create a complete maven project skeleton for a JEE application, a simplest project, helloworld. The whole application includes 2 modules, one web module and one ejb module. We still need one more project which is to package and assembly these 2 modules into one EAR, one complete JEE application.
Creating these 3 maven projects are sufficient to illustrate a complete JEE application structure.
We also hope this application complies with JEE 7 specification, is able to deploy on weblogic12c, and support JDK 8 runtime environment.

EJB module

1. pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    ...
    <packaging>ejb</packaging>
    ...
    <build>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-ejb-plugin</artifactId>
            <version>2.5.1</version>
            <configuration>
                <ejbVersion>3.1</ejbVersion>
            </configuration>
        </plugin>
    </build>
    ...
    <dependencies>
        <dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-api</artifactId>
            <version>7.0</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
</project>

Key points:

• ejb packaging
• maven-ejb-plugin maven plugin
• javaee-api dependency

2. src/main/resources/META-INF/ejb-jar.xml

<ejb-jar version="3.1" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemalocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_1.xsd">
    <module-name>helloworld-ejb</module-name>
</ejb-jar>

This module name is used by container and is very useful to looks up resource within container.

WEB module

1. pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    ...
    <packaging>war</packaging>
    ...
    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>3.1.0</version>
                <configuration>
                    <failOnMissingWebXml>false</failOnMissingWebXml>
                </configuration>
            </plugin>
        </plugins>
    </build>
    ...
    <dependencies>
        <dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-web-api</artifactId>
            <version>7.0</version>
            <scope>provided</scope>
        </dependency>
    </dependencies>
    ...
</project>

Key points:

• war packaging
• maven-war-plugin plugin
• javaee-web-api dependency

2. src/main/webapp/WEB-INF/web.xml

<?xml version="1.0" encoding="UTF-8"?>

<web-app version="3.1" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd">

    <!--<module-name>helloworld-web</module-name>-->

    ...

</web-app>

web.xml is optional, if no this file application still works because nowadays servlet can be declared with annotation.
And please notice the module-name declared here. It would overwrite the context-root in container specific descriptor WEB-INF/weblogic.xml if you set and <module>/<context-root> in META-INF/application.xml. For example, if you set module-name helloworld-web the URL to access the application would become http://hostname:port/helloworld-web, the context-root is replaced by module-name. For context-root declaration priority sequence is web.xml > application.xml > weblogic.xml.

EAR (Assembly) module

1. pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    ...
    <packaging>ear</packaging>
    ...
    <build>
        <plugins>
            ...
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-ear-plugin</artifactId>
                <configuration>
                    <version>7</version>
                    <defaultLibBundleDir>lib</defaultLibBundleDir>
                    <skinnyWars>true</skinnyWars>
                    <modules>
                        <ejbModule>
                            <groupId>org.example</groupId>
                            <artifactId>helloworld-ejb</artifactId>
                            <bundleFileName>helloworld-ejb.jar</bundleFileName>
                        </ejbModule>
                        <webModule>
                            <groupId>org.example</groupId>
                            <artifactId>helloworld-web</artifactId>
                            <bundleFileName>helloworld-web.war</bundleFileName>
                        </webModule>
                    </modules>
                </configuration>
            </plugin>
        </plugins>
    </build>
 
    <dependencies>
        <dependency>
            <groupId>org.example</groupId>
            <artifactId>helloworld-jar</artifactId>
            <version>1.0-SNAPSHOT</version>
            <type>jar</type>
        </dependency>
        <dependency>
            <groupId>org.example</groupId>
            <artifactId>helloworld-ejb</artifactId>
            <version>1.0-SNAPSHOT</version>
            <type>ejb</type>
        </dependency>
    </dependencies>
</project>

Key point:

• ear packaging
• maven-ear-plugin plugin
• Declare the modules you want to package inside maven-ear-plugin configuration
• Add sub-modules as dependencies 

2. application.xml

<?xml version="1.0" encoding="UTF-8"?>

<application version="7" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/application_7.xsd">

    <display-name>helloworld</display-name>

    <!-- application name inside container -->

    <application-name>helloworld-app</application-name>

    <module>

        <ejb>helloworld-ejb.jar</ejb>

    </module>

    <module>

        <web>

            <web-uri>helloworld-web.war</web-uri>

            <!-- Higher priority than context-root of weblogic.xml. The highest is module-name of web.xml -->

            <context-root>/helloworld</context-root>

        </web>

    </module>

</application>

Some other maven settings you may consider

1. Create parent pom to put sharing settings within modules
2. Config maven-compiler-plugin plugin. Specify source code java version and target version.
3. Config maven-dependency-plugin plugin

Java Util Logging (jul)

Java Util Logging(jul) is the logging tool which is naturally supported by JRE. It's out of box feature of JRE. So it's very convenient for those applications don't care logging records.

• JUL API and implementation are inside Java SE API
• JUL default configuration is inside JRE

Sample code

import java.util.logging.Logger;

public class Demo {
   
    private static final Logger LOGGER = Logger.getLogger(Demo.class.getName());
   
    public static void main(String[] args){
        LOGGER.info("Current Logger = " + LOGGER.getClass().getName());
       
        LOGGER.finest("finest log");
        LOGGER.finer("finer log");
        LOGGER.fine("fine log");
        LOGGER.config("config log");
        LOGGER.info("info log");
        LOGGER.warning("warning log");
        LOGGER.severe("severe log");
    }
   
}

You can directly execute this segment of code.

Default configuration

JUL default configuration adopted by JRE is /$JAVA_HOME/jre/lib/logging.properties. It output messages to console and only output INFO and above levels messages.

Using your own configuration

Create a properties file, named logging.properties

handlers=java.util.logging.FileHandler, java.util.logging.ConsoleHandler
.level=FINEST

java.util.logging.ConsoleHandler.level=FINEST
java.util.logging.ConsoleHandler.formatter=java.util.logging.SimpleFormatter

java.util.logging.FileHandler.level=INFO
java.util.logging.FileHandler.pattern=%h/jul%u.log
java.util.logging.FileHandler.limit=50000
java.util.logging.FileHandler.count=1
java.util.logging.FileHandler.formatter=java.util.logging.SimpleFormatter

Pass this configuration file by jvm system property option, -Djava.util.logging.config.file=/<your_dir>/logging.properties.