Disclaimer:
Started with simple settings (with
not even JUnit J.)
Pre-requisite:
1.
Jdk (tested with 1.8)
2.
Tomcat (tested with 8)
3.
Eclipse (tested with Mars)
Steps:
1.
Create a Maven project in Eclipse
Create a blank web-project with
maven-archtype-web
2.
Add dependencies in Maven
a. Add
jersey-bundle
b. Ensure
java 1.8 is used (not 1.5 as the default is set)
Pom.xml:
<dependencies>
<dependency>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-bundle</artifactId>
<version>1.19</version>
</dependency>
</dependencies>
<build>
<finalName>pidev</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
3.
Add Tomcat server library in Eclipse AND include
in Order and Export
·
Build Path -> Configure Build Path -> Libraries
-> Add Library -> Server Runtime -> Apache Tomcat 8.0
4.
Configure Jersey to listen for URI
<servlet>
<servlet-name>Jersey Web
Application</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value><your
package></param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Jersey Web
Application</servlet-name>
<url-pattern>/rest/*</url-pattern>
</servlet-mapping>
(Note that if the url-pattern is
/* then url to address doesn’t need “rest” in the URI J)
5.
Write code
package <your package>;
import
javax.ws.rs.GET;
import
javax.ws.rs.Path;
import
javax.ws.rs.PathParam;
import
javax.ws.rs.Produces;
@Path("/xmlapi")
public class XMLAPI {
@GET
@Produces("application/xml")
public String echo() {
return ("<xmlapi>default
echo</xmlapi>");
}
@Path("{c}")
@GET
@Produces("application/xml")
public String echo(@PathParam("c") String c) {
return ("<xmlapi>"+c+"</xmlapi>");
}
}
For json
package <your package>;
import
javax.ws.rs.GET;
import
javax.ws.rs.Path;
import
javax.ws.rs.PathParam;
import
javax.ws.rs.Produces;
@Path("/jsonapi")
public class JsonAPI {
@GET
@Produces("application/json")
public String echo() {
return "{\"message\":
\"default echo\"}";
}
@Path("{c}")
@GET
@Produces("application/xml")
public String echo(@PathParam("c") String c) {
return "{\"message\":
\"" + c + "\"}";
}
}
6.
Build and deploy
·
Maven -> Update project
·
Run project in Apache Tomcat
7.
Access the service
Output:
<?xml
version="1.0"?>
<xmlapi>default
echo</xmlapi>
Output:
<?xml
version="1.0"?>
<xmlapi>hi</xmlapi>
Potential problems:
1.
Project don’t compile:
Java compiler level does not
match the version of the installed Java project facet.
JAX-RS (REST Web Services) 2.0
requires Java 1.6 or newer.
One or more constraints have
not been satisfied.
Maven default uses 1.5 J
Solution:
Add/update build element of
pom.xml
<build>
<finalName><Project name></finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
2.
Jersey didn’t load your mapping
com.sun.jersey.api.core.ScanningResourceConfig.init
No provider classes found.
Solution:
In web.xml ensure that correct
package is specified in init-param
<servlet>
<servlet-name>Jersey Web
Application</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value><your
package></param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
3.
Status 500 UriBuilder
Duplicate UriBuilder J
Usually it happens if you try different dependencies and one of those dependencies
downloads it for you (e.g. jersey-bundle with jersey-server or
jersey-apache-connector)
Solution:
Remove javax.ws.rs-api.jar.
