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In JAX-RS, entire JSON string is being posted

I have a simple Jersey POST method that accepts JSON. I am using SOAP UI to test, using POST and media type application/JSON.
Within the request body I have JSON:
{
email:"test"
}
When I test this, the string I expect to come into the service as test actually comes in as the entire JSON string. Not sure what's wrong here, it should work according to the docs.
#POST
#Path("/TEST")
#Consumes(MediaType.APPLICATION_JSON)
public Response testJaxRs(String email){
// email = "{
// email:"test"
// }"
return Response.ok().build();
}

If you do not want to deserialize it to a bean, then you can accept the post body as a map of key-value pairs. For example:
public Response testJaxRs(Map<String, String> body) {
body.get("email") // "test"
...

You need a bean
public class Email{
private String email;
//getters&setters
}
public Response testJaxRs(Email emailBean){
Note that you need to add the dependencies to decode json. e.g Jackson and add this mapping to jersey servlet in web.xml> See full example here: https://www.mkyong.com/webservices/jax-rs/json-example-with-jersey-jackson/
<web-app ...>
<servlet>
<servlet-name>jersey-servlet</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>com.yourpackage</param-value>
</init-param>
<init-param>
<param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
<param-value>true</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>

If you're using Jersey 1.x, then to receive your Json as an object you need to declare the POJO and annotate it with javax.xml.bind.annotation.XmlRootElement:
#XmlRootElement
public class EmailTest{
String email;
public String getEmail(){
return this.email;
}
public void setEmail(String email) {
this.email = email;
}
}
Then you have to use this class in your controller:
#POST
#Path("/TEST")
#Consumes(MediaType.APPLICATION_JSON)
public Response testJaxRs(Email email){
System.out.println(email.getEmail()); // prints "test"
return Response.ok().build();
}
Finally you've to add com.sun.jersey.config.property.packages as <init-param> of your servlet adding the package or packages (separated by ,) pointing to your controller packages. For example in your web.xml:
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value>org.app.controllers</param-value>
</init-param>

Jersey: Unable to Get Sub-Sub-Resource

I have a web application implementing REST API using Jersey. The web container id Tomcat
Here is a summary of the API:
/rest/patients
Gets a list of patients' metadata.
/rest/patients/{id}
Gets detailed data about a specific patient.
/rest/patients/{id}/visits
Gets a list of visits` metadata for a specific patient.
/rest/patients/{id}/visits/{visitId}
Gets detailed data about a specific visit of a specific patient.
My problem is that I can't get the sub-sub resources. For example, when I request /rest/patients/1 the detailed data of patient #1 is received correctly.
But when I request /rest/patients/1/visits I get 404 error, and the flow doesn't even enter the getVisits() method.
It looks like that when a request for a specific patient id received (patients/{id}), Jersey is directing it correctly from PatientsMetadataResource to PatientsResource.
But when a visits sub-sub-resource is being requested (patients/{id}/visits), Jersey doesn't direct it into the PatientsResource.
So how can I direct a sub resource along with all of its sub-sub resources into the same class?
Code for PatientsMetadataResource (The name is a bit vague, and I need to change it):
#Path("/patients")
public class PatientsMetadataResource {
#GET
#Produces(MediaType.APPLICATION_JSON)
public Response getPatients(#QueryParam("page") int pageIndex) {
//.... Loads, Builds and returns the patients' metadata list correctly
}
#GET
#Produces(MediaType.APPLICATION_JSON)
#Path("/{uid:\\d+}")
public PatientResource getPatient(#PathParam("uid") int uid) {
return new PatientResource(uid);
}
}
Code for PatientResource:
public class PatientResource {
private final int uid;
public PatientResource(int uid) {
this.uid = uid;
}
#GET
#Produces(MediaType.APPLICATION_JSON)
public Response getPatient() {
//Returns the patient correctly
System.out.println("A Patient was asked");
Patient patient = PersistentDataProvider.loadPatientByUid(uid);
return Response.ok(patient).build();
}
#GET
#Path("/visits")
#Produces(MediaType.APPLICATION_JSON)
public VisitsResource getVisits(#PathParam("uid") int patientUid) {
//The flow doesn't even enter here. A 404 is being returned instead.
System.out.println("Visits were asked");
return new VisitsResource(patientUid);
}
}
Code for Jersey part in web.xml:
<servlet>
<servlet-name>Jersey REST Service</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>il.co.site_building.dvardy.resources</param-value>
</init-param>
<init-param>
<param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
<param-value>true</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Jersey REST Service</servlet-name>
<url-pattern>/rest/*</url-pattern>
</servlet-mapping>

Sub-Resource Locators aren't supposed to have HTTP method annotations
// #GET <--- Remove this
// #Produces(MediaType.APPLICATION_JSON)
#Path("/{uid:\\d+}")
public PatientResource getPatient(#PathParam("uid") int uid) {
return new PatientResource(uid);
}
Their main purpose is simply to forward request to the sub-resource class, not GET/POST/etc anything. When Jersey sees that HTTP method annotation, it no longer gets treated as a sub-resource locator.
Also you don't need need to pass the id. It will get passed accordingly
#Path("parent")
class ParentResource {
#Path("{id}")
public ChildResource getChild() {
return new ChildResource();
}
}
class ChildResource {
#GET
public Response get(#PathParam("id") long id) {}
#GET
#Path("something")
public Response something(#PathParam("id") long id) {}
}
Here GET 'parent/1' goes to ChildResource.get, passing the path param and GET parent/1/something goes to ChilsResource.something, passing the path param

Swagger - Extending SwaggerSpecFilter

I'm trying to write my own Swagger API Filter to hide certain things from appearing in the API. I think I have a pretty good idea of what I should be doing but I must be missing something in the details.
I'm using Swagger Core 1.3.10 and Spring 3.1. Here's some of what I have now:
SwaggerApiAuthorizationFilter
public class SwaggerApiAuthorizationFilter implements SwaggerSpecFilter {
private final static Logger logger = LoggerFactory.getLogger(SwaggerApiAuthorizationFilter.class);
#Override
public boolean isOperationAllowed(Operation operation, ApiDescription api, Map<String, List<String>> params,
Map<String, String> cookies, Map<String, List<String>> headers) {
return true;
}
#Override
public boolean isParamAllowed(Parameter parameter, Operation operation, ApiDescription api, Map<String, List<String>> params,
Map<String, String> cookies, Map<String, List<String>> headers) {
// do not allow the documentation to be generated on parameters that have their access set to "internal"
if (parameter.paramAccess().isDefined() && parameter.paramAccess().get().equalsIgnoreCase("internal")) {
logger.debug("The following parameter has been hidden from the Swagger API documentation: " + parameter.name());
return false;
} else {
return true;
}
}
}
SwaggerServlet
public class SwaggerServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
private final static Logger logger = LoggerFactory.getLogger(SwaggerServlet.class);
BeanConfig beanConfig;
SwaggerApiAuthorizationFilter swaggerApiAuthorizationFilter;
public void setBeanConfig(BeanConfig beanConfig) {
this.beanConfig = beanConfig;
}
public void setSwaggerApiAuthorizationFilter(SwaggerApiAuthorizationFilter swaggerApiAuthorizationFilter) {
this.swaggerApiAuthorizationFilter = swaggerApiAuthorizationFilter;
}
#Override
public void init(ServletConfig servletConfig) throws ServletException {
try {
super.init(servletConfig);
beanConfig.setBasePath("/mbl/services");
beanConfig.setVersion("1.0");
beanConfig.setResourcePackage("com.whatever.resources");
beanConfig.setScan(true);
FilterFactory.setFilter(swaggerApiAuthorizationFilter);
logger.debug("The Swagger servlet has been initialized");
} catch (Exception e) {
e.printStackTrace();
}
}
}
spring config file
<!-- Swagger Configuration and Providers -->
<bean id="beanConfig" class="com.wordnik.swagger.jaxrs.config.BeanConfig">
<property name="title" value="Java API"/>
<property name="version" value="1.0" />
<property name="basePath" value="/mbl/services"/>
<property name="resourcePackage" value="com.whatever.resources"/>
<property name="scan" value="true"/>
</bean>
<bean id="swaggerApiAuthorizationFilter" class="com.whatever.util.SwaggerApiAuthorizationFilter" />
web.xml
<!-- Enabling Swagger servlet -->
<servlet>
<servlet-name>Swagger Servlet</servlet-name>
<servlet-class>com.whatever.web.SwaggerServlet</servlet-class>
<init-param>
<param-name>swagger.filter</param-name>
<param-value>com.whatever.util.SwaggerApiAuthorizationFilter</param-value>
</init-param>
<load-on-startup>-1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Swagger Servlet</servlet-name>
<url-pattern>/api-docs</url-pattern>
</servlet-mapping>
Resource class
public Response getUserInfo(
#Context HttpHeaders headers,
#ApiParam(name="brand", access="internal") #CookieParam(value = "brand") String brand) {
It appears that my SwaggerApiAuthorizationFilter isn't even being called. My guess is that something is wrong in my configuration either in the web.xml or the SwaggerServlet. Does anyone see anything above that looks incorrect or does anyone have any ideas?

I've just used the filter successfully. I had problems to make filter function properly. The problem was that there was a problem to find my filter's implemention class. When I changed the package to a place where swagger's class could access, everything funtioned correctly. Next, I just had to implement my logic on my filter class. My filter class implemented the interface SwaggerSpecFilter too. Best regards.
I'm using DefaultJaxrsConfig:
<servlet>
<servlet-name>Jersey2Config</servlet-name>
<servlet-class>io.swagger.jaxrs.config.DefaultJaxrsConfig</servlet-class>
<init-param>
<param-name>api.version</param-name>
<param-value>1.0.0</param-value>
</init-param>
<init-param>
<param-name>swagger.api.basepath</param-name>
<param-value>/my-service/service/</param-value>
</init-param>
<init-param>
<param-name>swagger.filter</param-name>
<param-value>mypackage.SwaggerFilter</param-value>
</init-param>
<load-on-startup>3</load-on-startup>
</servlet>

I'm just guessing but I think you need to implement Filter as well as the SwaggerSpecFilter interface instead of extending HttpServlet (looking at the source it does not appear SwaggerSpecFilter extends Filter as one would expect), then configure it as a filter in your web.xml instead of a servlet. It would be something like this:
<filter>
<filter-name>Swagger Filter</filter-name>
<filter-class>com.whatever.util.SwaggerApiAuthorizationFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>Swagger Filter</filter-name>
<url-pattern>/api-docs</url-pattern>
</filter-mapping>
Again, not sure if this will work but just a guess off the top of my head.

Rest JAX-RS exception, MessageBodyWriter not found

I am using Jersey 2.13
I get MessageBoddyWriter not found exception when I try to access a resource via a url in a browser.
Exception:
MessageBodyWriter not found for media type=application/json,
type=class java.util.ArrayList, genericType=java.util.List<com.webservices.entity.Book>.
I have another method that produces "APPLICATION_XML" and that seems to work fine.
#XmlRootElement
#XmlAccessorType(XmlAccessType.FIELD)
public class Book {
#XmlElement
private String name;
#XmlElement
private String author;
//getters setters
}
#GET
#Path("/json")
#Produces(MediaType.APPLICATION_JSON)
public List<Book> getJsonResponse(JAXBElement<Book> book){
return new ArrayList<Book>();
}
My thought was jersey would automatically find the "JacksonJsonProvider", a message writer class, provided by Jackson but it doesn't.
My lib folder:

According to mkyong jersey+jackson tutorial, you need to add com.sun.jersey.api.json.POJOMappingFeature param in your web.xml to integrate them
<servlet>
<servlet-name>jersey-serlvet</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>com.mkyong.rest</param-value>
</init-param>
<init-param>
<param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
<param-value>true</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>

Starting with Jersey 2.9, automatic discovery of converter classes has been disabled. You have to register the converter class of your JSON library with Jersey manually. Here is what I do (I'm using Genson):
#ApplicationPath( "/api/library" )
public class RestService extends Application {
#Override
public Set<Class<?>> getClasses( ) {
final Set<Class<?>> returnValue = new HashSet<Class<?>>( );
returnValue.add( GensonJsonConverter.class );
return returnValue;
}
}

If you want to make your application code support both xml and json you need to create a wrapper object to support the collection rather than returning a GenericType. The PojoMappingFeature will work as it uses the native Jackson ObjectMapper instead of using the jaxb annotations for marshalling the object.
If you want it to be portable the best solution is to create a simple wrapper object as such.
#XmlRootElement
public class Books {
private List<Book> books;
public Books() {
}
public Books(List<Book> books) {
this.books = books;
}
#XmlElement(name="book")
public List<Book> getBooks() {
return books;
}
public void setBooks(List<Book> books) {
this.books = books;
}
}
#GET
#Path("/json")
#Produces(MediaType.APPLICATION_JSON)
public Books getJsonResponse(JAXBElement<Book> book){
return new Books(new ArrayList<Book>());
}
If you decide you want to also support MediaType.APPLICATION_XML then this is required. This will also solve the json (jackson) problem.

How to initialize a Servlet during startup with parameters?

Can we write an argument constructor in a Servlet? If yes, how can you call?

Can we write an argument constructor in a Servlet?
Yes, you can but it is useless since the servlet container won't invoke it.
The proper way to do it is to use the init() method:
#Override
public void init() throws ServletException {
String foo = getInitParameter("foo");
String bar = getServletContext().getInitParameter("bar");
// ...
}
In this example, getInitParameter("foo") returns the value of the <init-param> of the specific <servlet> entry in web.xml, and getServletContext().getInitParameter("bar") returns the value of the independent <context-param> in web.xml.

The problem can be state more generically:
"According to the servlets (2.3)
specification, the servlets are
instantiated by the servlet engine by
invoking the no-arg constructor. How
can I initialize a servlet properly
given that correct initialization
depends on the
central/global/unique/application
configuration?"
Actually, you can use serlvets with constructor and/or initialize them as you like. However, it requires a little bit of plumbing.
Assuming you have a servlet with a constructor having arguments:
package org.gawi.example.servlets;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class SampleServlet extends HttpServlet
{
private final String mMessage;
public SampleServlet(String message)
{
mMessage = message;
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
response.setContentType("text/plain");
response.getWriter().write(mMessage);
}
}
The first thing you need is a unique servlet whithin your application, let's call it InitializationServlet, to create all the required instances. Those instances must then be exported in the servlet context to be retrieve by another servlet (explained later). The InitializationServlet may look like this:
package org.gawi.example.servlets;
import javax.servlet.*;
import javax.servlet.http.*;
public class InitializationServlet extends HttpServlet
{
public void init() throws ServletException
{
SampleServlet servletA = new SampleServlet("this is servlet A");
SampleServlet servletB = new SampleServlet("this is servlet B");
SampleServlet servletC = new SampleServlet("this is servlet C");
getServletContext().setAttribute("servletA", servletA);
getServletContext().setAttribute("servletB", servletB);
getServletContext().setAttribute("servletC", servletC);
}
}
You see that only the init() method has been provided. This servlet is not servicing any HTTP request. Its only purpose is to store the servlet in the ServletContext. Note that you could have also use this servlet to load your application configuration. So this can act as the web-application entry point, like the main(String[] args) method of a program. This might remind you of the ContextLoaderServlet of SpringSource.
The last piece is the DelegateServlet that will effectively be instantiated by the servlet container, only this servlet will forward all the pertinent method calls to the wrapped servlet instance:
package org.gawi.example.servlets;
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class DelegateHttpServlet extends HttpServlet
{
private static final String SERVLET_CONTEXT_KEY_INIT_PARAMETER = "servletContextKey";
private HttpServlet mServlet;
public void init(ServletConfig servletConfig) throws ServletException
{
super.init(servletConfig);
locateServlet(servletConfig);
mServlet.init(servletConfig);
}
private void locateServlet(ServletConfig servletConfig) throws ServletException
{
String servletContextAttributeName = servletConfig.getInitParameter(SERVLET_CONTEXT_KEY_INIT_PARAMETER);
if (servletContextAttributeName == null)
{
throw new ServletException("Unable to find init parameter '" + SERVLET_CONTEXT_KEY_INIT_PARAMETER + "'");
}
Object object = servletConfig.getServletContext().getAttribute(servletContextAttributeName);
if (object == null)
{
throw new ServletException("Unable to find " + servletContextAttributeName + " in servlet context.");
}
if (!(object instanceof HttpServlet))
{
throw new ServletException("Object is not an instance of"
+ HttpServlet.class.getName()
+ ". Class is "
+ object.getClass().getName()
+ ".");
}
mServlet = (HttpServlet) object;
}
public void destroy()
{
mServlet.destroy();
}
public void service(ServletRequest req, ServletResponse res) throws ServletException, IOException
{
mServlet.service(req, res);
}
}
During its initialization, the DelegateServlet will look-up the target servlet in the servlet context using the servletContextKey servlet initial argument.
The web.xml for such an application might look like that:
<?xml version="1.0" encoding="ISO-8859-1"?>
<!DOCTYPE web-app
PUBLIC "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
"http://java.sun.com/dtd/web-app_2_3.dtd">
<web-app>
<display-name>Example</display-name>
<description>Example web showing handling of servlets w/ constructors.</description>
<servlet>
<servlet-name>Initialization</servlet-name>
<servlet-class>org.gawi.example.servlets.InitializationServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet>
<servlet-name>A</servlet-name>
<servlet-class>org.gawi.example.servlets.DelegateHttpServlet</servlet-class>
<init-param>
<param-name>servletContextKey</param-name>
<param-value>servletA</param-value>
</init-param>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet>
<servlet-name>B</servlet-name>
<servlet-class>org.gawi.example.servlets.DelegateHttpServlet</servlet-class>
<init-param>
<param-name>servletContextKey</param-name>
<param-value>servletB</param-value>
</init-param>
<load-on-startup>3</load-on-startup>
</servlet>
<servlet>
<servlet-name>C</servlet-name>
<servlet-class>org.gawi.example.servlets.DelegateHttpServlet</servlet-class>
<init-param>
<param-name>servletContextKey</param-name>
<param-value>servletC</param-value>
</init-param>
<load-on-startup>4</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>A</servlet-name>
<url-pattern>/servlet/a</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>B</servlet-name>
<url-pattern>/servlet/b</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>C</servlet-name>
<url-pattern>/servlet/c</url-pattern>
</servlet-mapping>
<session-config>
<session-timeout>5</session-timeout>
</session-config>
</web-app>
Be sure to load the InitializationServlet first, using a low <load-on-startup> value.
The benefit of this approach is that HttpServlet objects can be handled like any other regular Java object or bean. Hence, it provides a better control over initialization: no more tricky stuff to do in the init() method, nor messy servlet init-arg handling.

You can't. Servlet is instantiated reflectively by container. If servlet spec have allowed arguments in constructor, you would have to have some complicated deployment descriptor like,
<servlet>
<servlet-name>MyServlet</servlet-name>
<servlet-class>MyServlet</servlet-class>
<servlet-argument id="1" type="string">Test<servlet-argument>
<servlet-argument id="2" type="int">10</servlet-argument>
<load-on-startup>1</load-on-startup>
</servlet>
I guess no one wants that.

Constructors are objects managed by the application server.
For initialization, see the init() method.
Update:
Can I use a constructor in my servlet?
A: A servlet is a normal Java class, so when there are no custom
constructors, there is an implicit
default constructor with no arguments.
Servlet containers typically use the
Class.newInstance() method to load
servlets, so you must be careful to
add an explicit default constructor if
you add non-default constructors.
source: http://www.codestyle.org/java/servlets/FAQ.shtml