Tomcat is a servlet container and therefore does not provide some of the required JEE libraries out-of-the-box.
My basic set-up of a REST-based server, just as a demo (and no frameworks!), uses Java 15 with Tomcat 10.
The Maven POM:
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<?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>
<groupId>org.ajames</groupId>
<artifactId>JaxRsDemo</artifactId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>
<name>JaxRsDemo</name>
<properties>
<endorsed.dir>${project.build.directory}/endorsed</endorsed.dir>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<maven.compiler.source>15</maven.compiler.source>
<maven.compiler.target>15</maven.compiler.target>
</properties>
<dependencies>
<!-- the REST API -->
<dependency>
<groupId>jakarta.ws.rs</groupId>
<artifactId>jakarta.ws.rs-api</artifactId>
<version>3.0.0</version>
</dependency>
<!-- These next two are needed because we are using Tomcat, which -->
<!-- is not a full JEE server - it's just a servlet container. -->
<!-- the Jersey implementation -->
<dependency>
<groupId>org.glassfish.jersey.containers</groupId>
<artifactId>jersey-container-servlet</artifactId>
<version>3.0.2</version>
</dependency>
<!-- also needed for dependency injection -->
<dependency>
<groupId>org.glassfish.jersey.inject</groupId>
<artifactId>jersey-hk2</artifactId>
<version>3.0.2</version>
</dependency>
<!-- support for using Jackson (JSON) with Jersey -->
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-json-jackson</artifactId>
<version>3.0.2</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>15</source>
<target>15</target>
<compilerArguments>
<endorseddirs>${endorsed.dir}</endorseddirs>
</compilerArguments>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>3.3.1</version>
<configuration>
<failOnMissingWebXml>false</failOnMissingWebXml>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-dependency-plugin</artifactId>
<version>3.1.2</version>
<executions>
<execution>
<phase>validate</phase>
<goals>
<goal>copy</goal>
</goals>
<configuration>
<outputDirectory>${endorsed.dir}</outputDirectory>
<silent>true</silent>
<artifactItems>
<artifactItem>
<groupId>javax</groupId>
<artifactId>javaee-endorsed-api</artifactId>
<version>7.0</version>
<type>jar</type>
</artifactItem>
</artifactItems>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
</project>
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There is no web.xml needed - we use annotations instead.
For the main entry point:
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import jakarta.ws.rs.ApplicationPath;
import jakarta.ws.rs.core.Application;
@ApplicationPath("api")
public class App extends Application {
// the entry class - deliberately empty in this basic demo
}
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A demo resource:
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import jakarta.ws.rs.Consumes;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.POST;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.PathParam;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;
import jakarta.ws.rs.core.Response;
//
// Pingable at:
// http://localhost:8080/JaxRsDemo/api/demo/ping
//
@Path("/demo")
public class DemoResource {
@GET
@Path("/ping")
public Response ping() {
return Response.ok().entity("Service online").build();
}
@GET
@Path("/get/{id}")
@Produces(MediaType.APPLICATION_JSON)
public Response getNotification(@PathParam("id") int id) {
return Response.ok()
.entity(new DemoPojo(id, "test message"))
.build();
}
@POST
@Path("/post/")
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public Response postNotification(DemoPojo notification) {
return Response.status(201).entity(notification).build();
}
}
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The POJO:
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public class DemoPojo {
private int id;
private String message;
public DemoPojo() {
}
public DemoPojo(int id, String message) {
this.id = id;
this.message = message;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getMessage() {
return message;
}
public void setMessage(String message) {
this.message = message;
}
}
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Acknowledgement: The above is adapted and updated from the example here![]()
.
