Deploying Spring Boot Application on Oracle WebLogic Server

1- Objective of post

In this post, I will show you how to deploy a Spring Boot application on a WebLogic Server. This is a Web Server provided by Oracle, free of charge for downloading, developing, testing, prototyping, and demonstrating your application. The WebLogic is released based on the OTN license.
Ensure that you have installed the  WebLogic successfully . If not, you can refer to the way of installing WebLogic as in the following post:
In fact,  Spring Boot application can be packaged into an Executable JAR file. With this file, you can run the application directly without deploying it on any Web Server. The Executable JAR file can not be compatible with all Web servers, therefore, if you want to deploy it on a Web server, you need to package the Spring Boot application into a WAR file.

2- Edit code

I has a  Spring Boot project here, developed with  Eclipse IDE. When creating a  Spring Boot, you have 2 choices to package this project such as  WAR or  JAR.
When you create a  Spring Boot project with  "Packaging = War" option, Eclipse will create 2 classes such as  "AbcApplication & ServletInitializer" for you.  WAR files are suitable for being deployed on  Web Servers.
While, if you create a  Spring Boot with the  "Packaging = Jar" choice, only one  AbcApplication class will be created. When the  Spring Boot application is packed into the  JAR file, it can be independently executabe without being deployed on any  Web Server. But the   JAR file is not suitable to be deployed on  Web Servers.

WAR File.

If you have an available  Spring Boot, you need to correct packaging method into  WAR:
On the  Eclipse, open the  pom.xml file, and change packaging method into  war.

If your project doesn't have a ServletInitializer class, create it.

ServletInitializer.java
package org.o7planning.example;

import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.web.servlet.support.SpringBootServletInitializer;

public class ServletInitializer extends SpringBootServletInitializer {

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(SpringBootWebLogicApplication.class);
    }

}
Add the following configuration snippet to the  pom.xml:
** pom.xml **
<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-tomcat</artifactId>
    <scope>provided</scope>
</dependency>
If there are more than one  Application class in your project, please tell the  Spring Boot which class will be used for your application.
** pom.xml **
<properties>
        <start-class>org.o7planning.example.OtherSpringBootWebApplication</start-class>
</properties>

weblogic.xml & dispatcherServlet-servlet.xml

Create the 2 files such as  weblogic.xml & dispatcherServlet-servlet.xml in the  src/main/webapp/WEB-INF folder. It is noted that if this folder doesn't exist, please create it.
When your application is deployed on the  WebLogic, there will be  "context-root = /myweb", and you can change it by installing in the  weblogic.xml file:
weblogic.xml
<?xml version="1.0" encoding="UTF-8"?>
<wls:weblogic-web-app
        xmlns:wls="http://xmlns.oracle.com/weblogic/weblogic-web-app"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xsi:schemaLocation="http://xmlns.oracle.com/weblogic/weblogic-web-app
        http://xmlns.oracle.com/weblogic/weblogic-web-app/1.4/weblogic-web-app.xsd">

    <wls:context-root>/myweb</wls:context-root>
    <wls:container-descriptor>
        <wls:prefer-application-packages>
            <wls:package-name>org.slf4j.*</wls:package-name>
            <wls:package-name>org.springframework.*</wls:package-name>
        </wls:prefer-application-packages>
    </wls:container-descriptor>

</wls:weblogic-web-app>
dispatcherServlet-servlet.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd">
    
</beans>

3- Install Spring Boot

In the next step, you need to use  Maven to create   WAR file. You have to ensure that your  Eclipse is using   JDK instead of  JRE. If not, en error will occur in this process.
Right click on the Project and select:
  • Run As/Maven Install

At this moment, you will have a WAR file in the target folder of the project, you can use this file to deploy on the Tomcat Server.

4- Deploy on WebLogic

After packaging the application into a  WAR file, you can deploy this file on the  WebLogic:
There are two approaches to deploy the application to the  WebLogic Server .
  1. Copy the WAR file to a folder of the server, and then deploy it to the WebLogic. If you want to re-deploy the application, you only need to copy the new WAR file overwriting the old file and notify to the WebLogic to update the application.
  2. Use Upload function to deploy the WAR file.
OK, here, I have copied the  WAR file and install it to a folder in the server.
Press  "Activate Changes" to activate changes.
At  this moment, your application has  "Prepared" status (prepared). It isn't really activated to work.

Test

5- Undeploy

Undeploy an application on the  WebLogic, you must carry out 2 steps.
  1. Stop the application.
  2. Delete the application out of the WebLogic.

6- Update deployment

If your application is upgraded, you repackage the application and get a new WAR file. To redeploy the application, you have 2 ways to do:
  1. Undeploy the application and Redeploy.
  2. Copy a new WAR file overwriting the old WAR file and notify to the WebLogic to update the application again (or restart the WebLogic). Note: This way is used only when your application is deployed directly from the WAR file put on the server.
In the previous step, I have deployed the application directly from the  WAR file placed on an folder of the server. Now I will copy the new file to overwrite the old file.
And update the application: