Assumes that your Java, Maven, and eclipse are set up as per: Setting up Java, Maven, and eclipse
Step 1: Create a simple maven project using the maven “archetype” plugin.
1 2 | mvn archetype:generate -DgroupId=com.mytutorial -DartifactId=simple-spring-boot -DinteractiveMode=false |
The above command creates a folder “simple-spring-boot”
Step 2: import it into eclipse by choosing File –> Import –> Maven –> Existing Maven projects and select the folder “simple-spring-boot” you had just created with Maven.
Check “Maven Dependencies“:
Step 3: Add Spring boot dependency “spring-boot-starter-actuator“. The actuators enable production-ready features like health, metrics, info, dump, env etc to a Spring Boot application – without having to actually implement these things yourself.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 | <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/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.mytutorial</groupId> <artifactId>simple-spring-boot</artifactId> <packaging>jar</packaging> <version>1.0-SNAPSHOT</version> <name>simple-spring-boot</name> <url>http://maven.apache.org</url> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.4.RELEASE</version> </parent> <properties> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> </dependencies> </project> |
Note: The “parent” tag and the “dependency” tags having spring boot references.
What if you want to extend a different company level parent project?
You can use the Spring IO BOM (Bill Of Material) config
Note: dependency “spring-boot-dependencies” and the plugin “spring-boot-maven-plugin” with “repackage” goal.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 | <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/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.mytutorial</groupId> <artifactId>simple-spring-boot</artifactId> <packaging>jar</packaging> <version>1.0-SNAPSHOT</version> <name>simple-spring-boot</name> <url>http://maven.apache.org</url> <properties> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> <java.version>1.8</java.version> </properties> <dependencyManagement> <dependencies> <dependency> <!-- Import dependency management from Spring Boot --> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-dependencies</artifactId> <version>1.5.4.RELEASE</version> <type>pom</type> <scope>import</scope> </dependency> </dependencies> </dependencyManagement> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <!-- Build an executable jar --> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-jar-plugin</artifactId> <configuration> <archive> <manifest> <addClasspath>true</addClasspath> <classpathPrefix>lib/</classpathPrefix> <mainClass>com.mytutorial.App</mainClass> </manifest> </archive> </configuration> </plugin> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>1.5.4.RELEASE</version> <executions> <execution> <goals> <goal>repackage</goal> </goals> </execution> </executions> </plugin> </plugins> </build> </project> |
Step 4:Run the “mvn package” command.
1 2 3 | c:/projects/simple-spring-boot> mvn package |
Check “Maven Dependencies“: “spring-boot-starter-actuator” has added
May have to click “F5” within eclipse to refersh the projects.
Spring-boot brought in all these Spring framework jars
Step 5: Modify the “App.java” as shown below
1 2 3 4 5 6 7 8 9 10 11 12 13 | package com.mytutorial; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class App { public static void main( String[] args ) { System.out.println( "Hello Spring Boot!" ); } } |
Step 6: To run the jar file, you need to create a “META-INF/MANIFEST.MF” file. Using the maven jar plugin to generate the “MANIFEST.MF” file.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 | <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/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.mytutorial</groupId> <artifactId>simple-spring-boot</artifactId> <packaging>jar</packaging> <version>1.0-SNAPSHOT</version> <name>simple-spring-boot</name> <url>http://maven.apache.org</url> <properties> <maven.compiler.source>1.8</maven.compiler.source> <maven.compiler.target>1.8</maven.compiler.target> <java.version>1.8</java.version> </properties> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.4.RELEASE</version> </parent> <dependencies> <dependency> <groupId>junit</groupId> <artifactId>junit</artifactId> <scope>test</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-actuator</artifactId> </dependency> </dependencies> <build> <plugins> <plugin> <!-- Build an executable JAR --> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-jar-plugin</artifactId> <configuration> <archive> <manifest> <addClasspath>true</addClasspath> <classpathPrefix>lib/</classpathPrefix> <mainClass>com.mytutorial.App</mainClass> </manifest> </archive> </configuration> </plugin> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project> |
Note in pom.xml: “<mainClass>com.mytutorial.App</mainClass>”
1 | <mainClass>com.mytutorial.App</mainClass> |
Step 7: Ready to build the “jar” now.
1 2 3 | c:/projects/simple-spring-boot> mvn package |
The “target” directory will have the jar file “simple-spring-boot-1.0-SNAPSHOT.jar”
Deployable “jar” is built
Step 8: Deploy the very simple Spring boot application & run as shown below
right-click on the jar, and then select “properties” to get the full file path of the jar file.
“c:/projects/simple-spring-boot/target/simple-spring-boot-1.0-SNAPSHOT.jar”
1 2 3 | c:/projects/simple-spring-boot>java -jar c:/projects/simple-spring-boot/target/simple-spring-boot-1.0-SNAPSHOT.jar |
Output:
Hello Spring Boot!
Conclusion:
If you look at the packaged “simple-spring-boot-1.0-SNAPSHOT.jar” with
1 2 | jar -tvf target/simple-spring-boot-1.0-SNAPSHOT.jar |
you will get
UBER jar with Spring spring-boot-maven-plugin
Java does not provide any standard way to load nested jar files, so we use “uber” jars. An uber jar simply packages all classes, from all jars, into a single archive. The following plugin creates an uber jar.
1 2 3 4 5 6 7 | <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>1.5.4.RELEASE</version> </plugin> |
In the next tutorial I will expand this to a simple “RESTful” web service. Simple Spring Boot Restful Web Service Tutorial
