Merge branch 'feature/java-optional' into develop

src/main/java/com/leanstacks/ws/repository/AccountRepository.java

@@ -1,27 +1,28 @@
 package com.leanstacks.ws.repository;
 
+import java.util.Optional;
+
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.stereotype.Repository;
 
 import com.leanstacks.ws.model.Account;
 
 /**
- * The AccountRepository interface is a Spring Data JPA data repository for
- * Account entities. The AccountRepository provides all the data access
- * behaviors exposed by <code>JpaRepository</code> and additional custom
- * behaviors may be defined in this interface.
+ * The AccountRepository interface is a Spring Data JPA data repository for Account entities. The AccountRepository
+ * provides all the data access behaviors exposed by <code>JpaRepository</code> and additional custom behaviors may be
+ * defined in this interface.
  * 
  * @author Matt Warman
  */
 @Repository
 public interface AccountRepository extends JpaRepository<Account, Long> {
 
     /**
-     * Query for a single Account entities by username.
+     * Query for a single Account entity by username.
      * 
      * @param username The username value to query the repository.
-     * @return An Account or <code>null</code> if none found.
+     * @return An Optional Account.
      */
-    Account findByUsername(String username);
+    Optional<Account> findByUsername(String username);
 
 }

src/main/java/com/leanstacks/ws/security/AccountUserDetailsService.java

@@ -1,8 +1,8 @@
 package com.leanstacks.ws.security;
 
-import java.util.ArrayList;
-import java.util.Collection;
+import java.util.Optional;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -43,25 +43,21 @@ public class AccountUserDetailsService implements UserDetailsService {
     public UserDetails loadUserByUsername(final String username) throws UsernameNotFoundException {
         logger.info("> loadUserByUsername {}", username);
 
-        final Account account = accountService.findByUsername(username);
-        if (account == null) {
-            // Not found...
-            throw new UsernameNotFoundException("Invalid credentials.");
-        }
+        final Optional<Account> accountOptional = accountService.findByUsername(username);
+        final Account account = accountOptional
+                .orElseThrow(() -> new UsernameNotFoundException("Invalid credentials."));
 
         final Set<Role> roles = account.getRoles();
         if (roles == null || roles.isEmpty()) {
             // No Roles assigned to Account...
             throw new UsernameNotFoundException("Invalid credentials.");
         }
 
-        final Collection<GrantedAuthority> grantedAuthorities = new ArrayList<GrantedAuthority>();
-        for (final Role role : roles) {
-            grantedAuthorities.add(new SimpleGrantedAuthority(role.getCode()));
-        }
+        final Set<GrantedAuthority> authorities = roles.stream().map(role -> new SimpleGrantedAuthority(role.getCode()))
+                .collect(Collectors.toSet());
 
         final User userDetails = new User(account.getUsername(), account.getPassword(), account.isEnabled(),
-                !account.isExpired(), !account.isCredentialsexpired(), !account.isLocked(), grantedAuthorities);
+                !account.isExpired(), !account.isCredentialsexpired(), !account.isLocked(), authorities);
 
         logger.info("< loadUserByUsername {}", username);
         return userDetails;

src/main/java/com/leanstacks/ws/service/AccountService.java

@@ -1,5 +1,7 @@
 package com.leanstacks.ws.service;
 
+import java.util.Optional;
+
 import com.leanstacks.ws.model.Account;
 
 /**
@@ -19,8 +21,8 @@ public interface AccountService {
      * Find an Account by the username attribute value.
      * 
      * @param username A String username to query the repository.
-     * @return An Account instance or <code>null</code> if none found.
+     * @return An Optional wrapped Account.
      */
-    Account findByUsername(String username);
+    Optional<Account> findByUsername(String username);
 
 }

src/main/java/com/leanstacks/ws/service/AccountServiceBean.java

@@ -1,5 +1,7 @@
 package com.leanstacks.ws.service;
 
+import java.util.Optional;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -29,13 +31,13 @@ public class AccountServiceBean implements AccountService {
     private transient AccountRepository accountRepository;
 
     @Override
-    public Account findByUsername(final String username) {
+    public Optional<Account> findByUsername(final String username) {
         logger.info("> findByUsername");
 
-        final Account account = accountRepository.findByUsername(username);
+        final Optional<Account> accountOptional = accountRepository.findByUsername(username);
 
         logger.info("< findByUsername");
-        return account;
+        return accountOptional;
     }
 
 }

src/main/java/com/leanstacks/ws/service/GreetingService.java

@@ -1,6 +1,7 @@
 package com.leanstacks.ws.service;
 
-import java.util.Collection;
+import java.util.List;
+import java.util.Optional;
 
 import com.leanstacks.ws.model.Greeting;
 
@@ -19,17 +20,17 @@ public interface GreetingService {
     /**
      * Find all Greeting entities.
      * 
-     * @return A Collection of Greeting objects.
+     * @return A List of Greeting objects.
      */
-    Collection<Greeting> findAll();
+    List<Greeting> findAll();
 
     /**
-     * Find a single Greeting entity by primary key identifier.
+     * Find a single Greeting entity by primary key identifier. Returns an Optional wrapped Greeting.
      * 
-     * @param id A BigInteger primary key identifier.
-     * @return A Greeting or <code>null</code> if none found.
+     * @param id A Long primary key identifier.
+     * @return A Optional Greeting
      */
-    Greeting findOne(Long id);
+    Optional<Greeting> findOne(Long id);
 
     /**
      * Persists a Greeting entity in the data store.
@@ -50,7 +51,7 @@ public interface GreetingService {
     /**
      * Removes a previously persisted Greeting entity from the data store.
      * 
-     * @param id A BigInteger primary key identifier.
+     * @param id A Long primary key identifier.
      */
     void delete(Long id);
 

src/main/java/com/leanstacks/ws/service/GreetingServiceBean.java

@@ -1,11 +1,8 @@
 package com.leanstacks.ws.service;
 
-import java.util.Collection;
+import java.util.List;
 import java.util.Optional;
 
-import javax.persistence.EntityExistsException;
-import javax.persistence.NoResultException;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -83,12 +80,12 @@ public GreetingServiceBean(final GreetingRepository greetingRepository, final Me
     }
 
     @Override
-    public Collection<Greeting> findAll() {
+    public List<Greeting> findAll() {
         logger.info("> findAll");
 
         findAllMethodInvocationCounter.increment();
 
-        final Collection<Greeting> greetings = greetingRepository.findAll();
+        final List<Greeting> greetings = greetingRepository.findAll();
 
         logger.info("< findAll");
         return greetings;
@@ -97,19 +94,19 @@ public Collection<Greeting> findAll() {
     @Cacheable(value = Application.CACHE_GREETINGS,
             key = "#id")
     @Override
-    public Greeting findOne(final Long id) {
+    public Optional<Greeting> findOne(final Long id) {
         logger.info("> findOne {}", id);
 
         findOneMethodInvocationCounter.increment();
 
-        final Optional<Greeting> result = greetingRepository.findById(id);
+        final Optional<Greeting> greetingOptional = greetingRepository.findById(id);
 
         logger.info("< findOne {}", id);
-        return result.isPresent() ? result.get() : null;
+        return greetingOptional;
     }
 
     @CachePut(value = Application.CACHE_GREETINGS,
-            key = "#result.id")
+            key = "#result?.id")
     @Transactional
     @Override
     public Greeting create(final Greeting greeting) {
@@ -123,7 +120,7 @@ public Greeting create(final Greeting greeting) {
         if (greeting.getId() != null) {
             logger.error("Attempted to create a Greeting, but id attribute was not null.");
             logger.info("< create");
-            throw new EntityExistsException(
+            throw new IllegalArgumentException(
                     "Cannot create new Greeting with supplied id.  The id attribute must be null to create an entity.");
         }
 
@@ -142,15 +139,10 @@ public Greeting update(final Greeting greeting) {
 
         updateMethodInvocationCounter.increment();
 
-        // Ensure the entity object to be updated exists in the repository to
-        // prevent the default behavior of save() which will persist a new
+        // findOne returns an Optional which will throw NoSuchElementException when null.
+        // This will prevent the default behavior of save() which will persist a new
         // entity if the entity matching the id does not exist
-        final Greeting greetingToUpdate = findOne(greeting.getId());
-        if (greetingToUpdate == null) {
-            logger.error("Attempted to update a Greeting, but the entity does not exist.");
-            logger.info("< update {}", greeting.getId());
-            throw new NoResultException("Requested Greeting not found.");
-        }
+        final Greeting greetingToUpdate = findOne(greeting.getId()).get();
 
         greetingToUpdate.setText(greeting.getText());
         final Greeting updatedGreeting = greetingRepository.save(greetingToUpdate);

src/main/java/com/leanstacks/ws/web/api/GreetingController.java

@@ -1,11 +1,10 @@
 package com.leanstacks.ws.web.api;
 
-import java.util.Collection;
+import java.util.List;
+import java.util.Optional;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
 
-import javax.persistence.NoResultException;
-
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
@@ -61,7 +60,7 @@ public class GreetingController {
      * Web service endpoint to fetch all Greeting entities. The service returns the collection of Greeting entities as
      * JSON.
      * 
-     * @return A ResponseEntity containing a Collection of Greeting objects.
+     * @return A List of Greeting objects.
      */
     @ApiOperation(value = "${GreetingController.getGreetings.title}",
             notes = "${GreetingController.getGreetings.notes}",
@@ -73,10 +72,10 @@ public class GreetingController {
             dataType = "string",
             paramType = "header"))
     @GetMapping
-    public Collection<Greeting> getGreetings() {
+    public List<Greeting> getGreetings() {
         logger.info("> getGreetings");
 
-        final Collection<Greeting> greetings = greetingService.findAll();
+        final List<Greeting> greetings = greetingService.findAll();
 
         logger.info("< getGreetings");
         return greetings;
@@ -92,8 +91,7 @@ public Collection<Greeting> getGreetings() {
      * </p>
      * 
      * @param id A Long URL path variable containing the Greeting primary key identifier.
-     * @return A ResponseEntity containing a single Greeting object, if found, and a HTTP status code as described in
-     *         the method comment.
+     * @return A Greeting object, if found, and a HTTP status code as described in the method comment.
      */
     @ApiOperation(value = "${GreetingController.getGreeting.title}",
             notes = "${GreetingController.getGreeting.notes}",
@@ -107,14 +105,10 @@ public Collection<Greeting> getGreetings() {
     public Greeting getGreeting(@ApiParam("Greeting ID") @PathVariable final Long id) {
         logger.info("> getGreeting");
 
-        final Greeting greeting = greetingService.findOne(id);
-        if (greeting == null) {
-            logger.info("< getGreeting");
-            throw new NoResultException("Greeting not found.");
-        }
+        final Optional<Greeting> greetingOptional = greetingService.findOne(id);
 
         logger.info("< getGreeting");
-        return greeting;
+        return greetingOptional.get();
     }
 
     /**
@@ -124,12 +118,11 @@ public Greeting getGreeting(@ApiParam("Greeting ID") @PathVariable final Long id
      * </p>
      * <p>
      * If created successfully, the persisted Greeting is returned as JSON with HTTP status 201. If not created
-     * successfully, the service returns an empty response body with HTTP status 500.
+     * successfully, the service returns an ExceptionDetail response body with HTTP status 400 or 500.
      * </p>
      * 
      * @param greeting The Greeting object to be created.
-     * @return A ResponseEntity containing a single Greeting object, if created successfully, and a HTTP status code as
-     *         described in the method comment.
+     * @return A Greeting object, if created successfully, and a HTTP status code as described in the method comment.
      */
     @ApiOperation(value = "${GreetingController.createGreeting.title}",
             notes = "${GreetingController.createGreeting.notes}",
@@ -158,13 +151,12 @@ public Greeting createGreeting(@RequestBody final Greeting greeting) {
      * </p>
      * <p>
      * If updated successfully, the persisted Greeting is returned as JSON with HTTP status 200. If not found, the
-     * service returns an empty response body and HTTP status 404. If not updated successfully, the service returns an
-     * empty response body with HTTP status 500.
+     * service returns an ExceptionDetail response body and HTTP status 404. If not updated successfully, the service
+     * returns an empty response body with HTTP status 400 or 500.
      * </p>
      * 
      * @param greeting The Greeting object to be updated.
-     * @return A ResponseEntity containing a single Greeting object, if updated successfully, and a HTTP status code as
-     *         described in the method comment.
+     * @return A Greeting object, if updated successfully, and a HTTP status code as described in the method comment.
      */
     @ApiOperation(value = "${GreetingController.updateGreeting.title}",
             notes = "${GreetingController.updateGreeting.notes}",
@@ -194,7 +186,7 @@ public Greeting updateGreeting(@ApiParam("Greeting ID") @PathVariable("id") fina
      * </p>
      * <p>
      * If deleted successfully, the service returns an empty response body with HTTP status 204. If not deleted
-     * successfully, the service returns an empty response body with HTTP status 500.
+     * successfully, the service returns an ExceptionDetail response body with HTTP status 500.
      * </p>
      * 
      * @param id A Long URL path variable containing the Greeting primary key identifier.
@@ -223,14 +215,13 @@ public void deleteGreeting(@ApiParam("Greeting ID") @PathVariable("id") final Lo
      * </p>
      * <p>
      * If found, the Greeting is returned as JSON with HTTP status 200 and sent via Email. If not found, the service
-     * returns an empty response body with HTTP status 404.
+     * returns an Exception response body with HTTP status 404.
      * </p>
      * 
      * @param id A Long URL path variable containing the Greeting primary key identifier.
      * @param waitForAsyncResult A boolean indicating if the web service should wait for the asynchronous email
      *            transmission.
-     * @return A ResponseEntity containing a single Greeting object, if found, and a HTTP status code as described in
-     *         the method comment.
+     * @return A Greeting object, if found, and a HTTP status code as described in the method comment.
      */
     @ApiOperation(value = "${GreetingController.sendGreeting.title}",
             notes = "${GreetingController.sendGreeting.notes}",
@@ -250,11 +241,7 @@ public Greeting sendGreeting(@ApiParam("Greeting ID") @PathVariable("id") final
         Greeting greeting;
 
         try {
-            greeting = greetingService.findOne(id);
-            if (greeting == null) {
-                logger.info("< sendGreeting");
-                throw new NoResultException("Greeting not found.");
-            }
+            greeting = greetingService.findOne(id).get();
 
             if (waitForAsyncResult) {
                 final Future<Boolean> asyncResponse = emailService.sendAsyncWithResult(greeting);