/**
* JBoss, Home of Professional Open Source
* Copyright 2012, Red Hat, Inc., and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.acme.example.rest;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.logging.Logger;
import javax.ejb.Stateful;
import javax.enterprise.context.RequestScoped;
import javax.inject.Inject;
import javax.persistence.NoResultException;
import javax.validation.ConstraintViolation;
import javax.validation.ConstraintViolationException;
import javax.validation.ValidationException;
import javax.validation.Validator;
import javax.ws.rs.Consumes;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.WebApplicationException;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import com.acme.example.data.MemberRepository;
import com.acme.example.model.Member;
import com.acme.example.service.MemberRegistration;
/**
* JAX-RS Example
* <p/>
* This class produces a RESTful service to read/write the contents of the members table.
*/
@Path("/members")
@RequestScoped
@Stateful
public class MemberService {
@Inject
private Logger log;
@Inject
private Validator validator;
@Inject
private MemberRepository repository;
@Inject
MemberRegistration registration;
@GET
@Produces(MediaType.APPLICATION_JSON)
public List<Member> listAllMembers() {
return repository.findAllOrderedByName();
}
@GET
@Path("/{id:[0-9][0-9]*}")
@Produces(MediaType.APPLICATION_JSON)
public Member lookupMemberById(@PathParam("id") long id) {
Member member = repository.findById(id);
if (member == null) {
throw new WebApplicationException(Response.Status.NOT_FOUND);
}
return member;
}
/**
* Creates a new member from the values provided. Performs validation, and will return a JAX-RS response with either
* 200 ok, or with a map of fields, and related errors.
*/
@POST
@Consumes(MediaType.APPLICATION_JSON)
@Produces(MediaType.APPLICATION_JSON)
public Response createMember(Member member) {
Response.ResponseBuilder builder = null;
try {
//Validates member using bean validation
validateMember(member);
registration.register(member);
//Create an "ok" response
builder = Response.ok();
} catch (ConstraintViolationException ce) {
//Handle bean validation issues
builder = createViolationResponse(ce.getConstraintViolations());
} catch (ValidationException e) {
//Handle the unique constrain violation
Map<String, String> responseObj = new HashMap<String, String>();
responseObj.put("email", "Email taken");
builder = Response.status(Response.Status.CONFLICT).entity(responseObj);
} catch (Exception e) {
// Handle generic exceptions
Map<String, String> responseObj = new HashMap<String, String>();
responseObj.put("error", e.getMessage());
builder = Response.status(Response.Status.BAD_REQUEST).entity(responseObj);
}
return builder.build();
}
/**
* <p>Validates the given Member variable and throws validation exceptions based on the type of error.
* If the error is standard bean validation errors then it will throw a ConstraintValidationException
* with the set of the constraints violated.</p>
* <p>If the error is caused because an existing member with the same email is registered it throws a regular
* validation exception so that it can be interpreted separately.</p>
*
* @param member Member to be validated
* @throws ConstraintViolationException If Bean Validation errors exist
* @throws ValidationException If member with the same email already exists
*/
private void validateMember(Member member) throws ConstraintViolationException, ValidationException {
//Create a bean validator and check for issues.
Set<ConstraintViolation<Member>> violations = validator.validate(member);
if (!violations.isEmpty()) {
throw new ConstraintViolationException(new HashSet<ConstraintViolation<?>>(violations));
}
//Check the uniqueness of the email address
if (emailAlreadyExists(member.getEmail())) {
throw new ValidationException("Unique Email Violation");
}
}
/**
* Creates a JAX-RS "Bad Request" response including a map of all violation fields, and their message.
* This can then be used by clients to show violations.
*
* @param violations A set of violations that needs to be reported
* @return JAX-RS response containing all violations
*/
private Response.ResponseBuilder createViolationResponse(Set<ConstraintViolation<?>> violations) {
log.fine("Validation completed. violations found: " + violations.size());
Map<String, String> responseObj = new HashMap<String, String>();
for (ConstraintViolation<?> violation : violations) {
responseObj.put(violation.getPropertyPath().toString(), violation.getMessage());
}
return Response.status(Response.Status.BAD_REQUEST).entity(responseObj);
}
/**
* Checks if a member with the same email address is already registered. This is the only way to
* easily capture the "@UniqueConstraint(columnNames = "email")" constraint from the Member class.
*
* @param email The email to check
* @return True if the email already exists, and false otherwise
*/
public boolean emailAlreadyExists(String email) {
Member member = null;
try {
member = repository.findByEmail(email);
} catch (NoResultException e) {
// ignore
}
return member != null;
}
}