Java – The jsonschema2pojo maven plugin does not generate Java classes

I’m trying to get the Java model for FHIR R4 specification. To accomplish this, I downloaded the JSON Schema, and I tried using the jsonschema2pojo maven plugin to generate the source code.

I created a simple Maven project and put the JSON schema under src/main/resources/schema. So, I defined the following pom:

<pre class=”lang-xml prettyprint-override”><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>
<groupId>com.example</groupId>
<artifactId>fhir-generator</artifactId>
<version>0.0.1-SNAPSHOT</version>

<dependencies>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-lang3</artifactId>
<version>3.9</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-databind</artifactId>
<version>2.9.9.2</version>
</dependency>
</dependencies>

<build>

<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>

<plugin>
<groupId>org.jsonschema2pojo</groupId>
<artifactId>jsonschema2pojo-maven-plugin</artifactId>
<version>1.0.1</version>
<configuration>
<sourceDirectory>${basedir}/src/main/resources/schema</sourceDirectory>
<targetPackage>com.example.fhir</targetPackage>
<useCommonsLang3>true</useCommonsLang3>
</configuration>
<executions>
<execution>
<goals>
<goal>generate</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>

</project>


When I run the target package, I get the following output:

[INFO] Scanning for projects...
[WARNING] 
[WARNING] Some problems were encountered while building the effective model for come.example:fhir-generator:jar:0.0.1-SNAPSHOT
[WARNING] 'build.plugins.plugin.version' for org.apache.maven.plugins:maven-compiler-plugin is missing. @ line 24, column 12
[WARNING] 
[WARNING] It is highly recommended to fix these problems because they threaten the stability of your build.
[WARNING] 
[WARNING] For this reason, future Maven versions might no longer support building such malformed projects.
[WARNING] 
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building fhir-generator 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- jsonschema2pojo-maven-plugin:1.0.1:generate (default) @ fhir-generator ---
[WARNING] useCommonsLang3 is deprecated. Please remove it from your config.
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ fhir-generator ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 1 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ fhir-generator ---
[INFO] Nothing to compile - all classes are up to date
[INFO] 
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ fhir-generator ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources, i.e. build is platform dependent!
[INFO] Copying 0 resource
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ fhir-generator ---
[INFO] Nothing to compile - all classes are up to date
[INFO] 
[INFO] --- maven-surefire-plugin:2.12.4:test (default-test) @ fhir-generator ---
[INFO] 
[INFO] --- maven-jar-plugin:2.4:jar (default-jar) @ fhir-generator ---
[INFO] Building jar: Z:\work\backend\fhir-generator\target\fhir-generator-0.0.1-SNAPSHOT.jar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 2.921 s
[INFO] Finished at: 2019-07-30T11:21:25+02:00
[INFO] Final Memory: 12M/208M
[INFO] ------------------------------------------------------------------------

The problem is that no classes are generated in the target/generated-sources folder. Any ideas? Tnx in advance

By default, the jsonschema2pojo plugin generates files to the target/java-gen/ folder instead of the folder you specify.