#139 Convert usages of Optional to Kotlin nullables - WIP

generators/entity-server/templates/src/main/kotlin/package/common/get_template.ejs

@@ -23,6 +23,6 @@
     const returnPrefix = returnDirectly ? 'return' : 'val ' + instanceName + ' =';
     if (!viaService) {
 %>
-        <%- returnPrefix %> <%= entityInstance %>Repository.<% if (fieldsContainOwnerManyToMany === true) { %>findOneWithEagerRelationships(id)<% } else { %>findById(id)<% } %><% if (dto !== 'mapstruct') { %><% } else { %>
-            .map(<%= entityToDtoReference %>)<% } } else { %>
+        <%- returnPrefix %> <%= entityInstance %>Repository.<% if (fieldsContainOwnerManyToMany === true) { %>findOneWithEagerRelationships(id)<% } else { %>findByIdOrNull(id)<% } %><% if (dto !== 'mapstruct') { %><% } else { %>
+            ?.let(<%= entityToDtoReference %>)<% } } else { %>
         <%- returnPrefix %> <%= entityInstance %>Service.findOne(id)<% } %>

generators/entity-server/templates/src/main/kotlin/package/repository/EntityRepository.kt.ejs

@@ -46,7 +46,6 @@ import org.springframework.stereotype.Repository
 <%_ if (databaseType === 'sql' || databaseType === 'mongodb') { _%>
 <%_ if (fieldsContainOwnerManyToMany) { _%>
 
-import java.util.Optional
     <%_ } _%>
 <%_ } _%>
 <%_ if (databaseType === 'cassandra') { _%>
@@ -84,7 +83,7 @@ interface <%=entityClass%>Repository : <% if (databaseType === 'sql') { %>JpaRep
 
     @Query("select <%= entityInstance %> from <%= asEntity(entityClass) %> <%= entityInstance %><% for (idx in relationships) {
     if (relationships[idx].relationshipType === 'many-to-many' && relationships[idx].ownerSide === true) { %> left join fetch <%=entityInstance%>.<%=relationships[idx].relationshipFieldNamePlural%><%} }%> where <%=entityInstance%>.id =:id")
-    fun findOneWithEagerRelationships(@Param("id") id: <%= primaryKeyType %>): Optional<<%= asEntity(entityClass) %>>
+    fun findOneWithEagerRelationships(@Param("id") id: <%= primaryKeyType %>): <%= asEntity(entityClass) %>?
     <%_
         } else if (databaseType === 'mongodb')  { _%>
 
@@ -95,7 +94,7 @@ interface <%=entityClass%>Repository : <% if (databaseType === 'sql') { %>JpaRep
     fun findAllWithEagerRelationships(): MutableList<<%= asEntity(entityClass) %>>
 
     @Query("{'id': ?0}")
-    fun findOneWithEagerRelationships(id: <%= primaryKeyType %>): Optional<<%= asEntity(entityClass) %>>
+    fun findOneWithEagerRelationships(id: <%= primaryKeyType %>): <%= asEntity(entityClass) %>?
     <%_ }
     } _%>
 }

generators/entity-server/templates/src/main/kotlin/package/service/EntityService.kt.ejs

@@ -35,7 +35,6 @@ import org.springframework.data.domain.Pageable
 import reactor.core.publisher.Flux
 <%_ } _%>
 
-import java.util.Optional
 <%_ if (databaseType === 'cassandra') { _%>
 import java.util.UUID
 <%_ } _%>
@@ -92,7 +91,7 @@ interface <%= entityClass %>Service {
      * @param id the id of the entity.
      * @return the entity.
      */
-    fun findOne(id: <%= primaryKeyType %>): Optional<<%= instanceType %>>
+    fun findOne(id: <%= primaryKeyType %>): <%= instanceType %>?
 
     /**
      * Delete the "id" <%= entityInstance %>.

generators/entity-server/templates/src/main/kotlin/package/service/impl/EntityServiceImpl.kt.ejs

@@ -43,6 +43,8 @@ package <%= packageName %>.service<% if (service === 'serviceImpl') { %>.impl<%
 import <%= packageName %>.service.<%= entityClass %>Service<% } %>
 import <%= packageName %>.domain.<%= asEntity(entityClass) %>
 import <%= packageName %>.repository.<%= entityClass %>Repository
+import org.springframework.data.repository.findByIdOrNull
+
 <%_ if (isUsingMapsId === true) { _%>
 import <%=packageName%>.repository.<%= mapsIdAssoc.otherEntityNameCapitalized %>Repository
 <%_ } _%>
@@ -70,7 +72,6 @@ import org.springframework.transaction.annotation.Transactional
 import reactor.core.publisher.Flux
 <%_ } _%>
 
-import java.util.Optional
 <%_ if (databaseType === 'cassandra') { _%>
 import java.util.UUID
 <%_ } _%>
@@ -153,7 +154,7 @@ class <%= serviceClassName %>(
     <%_ if (databaseType === 'sql') { _%>
     @Transactional(readOnly = true)
     <%_ } _%>
-    <% if (service === 'serviceImpl') { %>override <% } %>fun findOne(id: <%= primaryKeyType %>): Optional<<%= instanceType %>> {
+    <% if (service === 'serviceImpl') { %>override <% } %>fun findOne(id: <%= primaryKeyType %>): <%= instanceType %>? {
         log.debug("Request to get <%= entityClass %> : {}", id)<%- include('../../common/get_template', {asEntity, asDto, viaService, returnDirectly:true}); -%>
     }
 

generators/entity-server/templates/src/main/kotlin/package/web/rest/EntityResource.kt.ejs

@@ -104,8 +104,8 @@ import reactor.core.publisher.Flux
 import javax.validation.Valid
 <%_ } _%>
 import java.net.URI
-import java.net.URISyntaxException<% if (isUsingMapsId === true) { %>
-import java.util.Objects<% } %>
+import java.net.URISyntaxException
+import java.util.*
 <%_ if (databaseType === 'cassandra') { _%>
 import java.util.UUID
 <%_ } _%>
@@ -255,7 +255,7 @@ _%><%- include('../../common/inject_template', {viaService: viaService, construc
     <%_ } _%>
     fun get<%= entityClass %>(@PathVariable id: <%= primaryKeyType %>): ResponseEntity<<%= instanceType %>> {
         log.debug("REST request to get <%= entityClass %> : {}", id)<%- include('../../common/get_template', {asEntity, asDto, viaService, returnDirectly:false}); -%>
-        return ResponseUtil.wrapOrNotFound(<%= instanceName %>)
+        return ResponseUtil.wrapOrNotFound(Optional.ofNullable(<%= instanceName %>))
     }
 <%_ if (!readOnly) { _%>
     /**

generators/server/index.js

@@ -115,4 +115,16 @@ module.exports = class extends ServerGenerator {
         // Here we are not overriding this phase and hence its being handled by JHipster
         return super._end();
     }
+
+    /**
+     * Construct nullable or Mono (for reactive) type
+     * @param {String} classType entity name
+     */
+    // TODO test me
+    nullableOrMono(classType) {
+        if (this.reactive) {
+            return `Mono<${classType}>`;
+        }
+        return `${classType}?`;
+    }
 };

generators/server/templates/src/main/kotlin/package/client/JWT_UserFeignClientInterceptor.kt.ejs

@@ -29,6 +29,7 @@ private const val BEARER_TOKEN_TYPE = "Bearer"
 @Component
 class UserFeignClientInterceptor : RequestInterceptor {
 
-    override fun apply(template: RequestTemplate) =
-        getCurrentUserJWT().ifPresent { s -> template.header(AUTHORIZATION_HEADER,"$BEARER_TOKEN_TYPE $s") }
+    override fun apply(template: RequestTemplate) {
+        getCurrentUserJWT()?.let { s -> template.header(AUTHORIZATION_HEADER, "$BEARER_TOKEN_TYPE $s") }
+    }
 }

generators/server/templates/src/main/kotlin/package/config/ReactivePageableHandlerMethodArgumentResolver.kt.ejs

@@ -19,7 +19,6 @@
 package <%=packageName%>.config
 
 import java.lang.reflect.Method
-import java.util.Optional
 
 import org.springframework.beans.factory.annotation.Qualifier
 import org.springframework.core.MethodParameter
@@ -156,29 +155,25 @@ constructor(
     ): Pageable {
         assertPageableUniqueness(methodParameter)
 
-        val defaultOrFallback = getDefaultFromAnnotationOrFallback(methodParameter)!!.toOptional()
+        val defaultOrFallback = getDefaultFromAnnotationOrFallback(methodParameter)
 
         val page = parseAndApplyBoundaries(pageString, Integer.MAX_VALUE, true)
         val pageSize = parseAndApplyBoundaries(pageSizeString, maxPageSize, false)
 
-        if (!(page.isPresent && pageSize.isPresent) && !defaultOrFallback.isPresent) {
+        if (page != null && pageSize != null && defaultOrFallback == null) {
             return Pageable.unpaged()
         }
 
-        val p = page.orElseGet {
-            defaultOrFallback.map { it.pageNumber }.orElseThrow { IllegalStateException() }
-        }
-        var ps = pageSize.orElseGet {
-            defaultOrFallback.map { it.pageSize }.orElseThrow { IllegalStateException() }
-        }
-
+        val p = page ?: defaultOrFallback?.pageNumber ?: throw IllegalStateException()
+        var ps = pageSize ?: defaultOrFallback?.pageSize ?: throw IllegalStateException()
+
         // Limit lower bound
-        ps =
-            if (ps < 1) defaultOrFallback.map { it.pageSize }.orElseThrow { IllegalStateException() } else ps
+        ps = if (ps < 1) defaultOrFallback?.pageSize ?: throw IllegalStateException() else ps
         // Limit upper bound
         ps = if (ps > maxPageSize) maxPageSize else ps
-
-        return PageRequest.of(p, ps, defaultOrFallback.map<Sort> { it.sort }.orElseGet { Sort.unsorted() })
+
+        return PageRequest.of(p, ps, defaultOrFallback?.sort ?: Sort.unsorted())
+
     }
 
     /**
@@ -218,16 +213,16 @@ constructor(
      * @param shiftIndex whether to shift the index if [.oneIndexedParameters] is set to true.
      * @return the parsed integer.
      */
-    private fun parseAndApplyBoundaries(@Nullable parameter: String?, upper: Int, shiftIndex: Boolean): Optional<Int> {
+    private fun parseAndApplyBoundaries(@Nullable parameter: String?, upper: Int, shiftIndex: Boolean): Int? {
         if (!StringUtils.hasText(parameter)) {
-            return Optional.empty()
+            return null
         }
 
         return try {
             val parsed = Integer.parseInt(parameter!!) - if (isOneIndexedParameters && shiftIndex) 1 else 0
-            Optional.of(if (parsed < 0) 0 else if (parsed > upper) upper else parsed)
+            if (parsed < 0) 0 else if (parsed > upper) upper else parsed
         } catch (e: NumberFormatException) {
-            Optional.of(0)
+            0
         }
     }
 

generators/server/templates/src/main/kotlin/package/config/ReactiveSortHandlerMethodArgumentResolver.kt.ejs

@@ -18,8 +18,6 @@
 -%>
 package <%=packageName%>.config
 
-import java.util.Optional
-
 import org.springframework.beans.factory.annotation.Qualifier
 import org.springframework.core.MethodParameter
 import org.springframework.core.annotation.AnnotationUtils
@@ -133,13 +131,10 @@ class ReactiveSortHandlerMethodArgumentResolver : SyncHandlerMethodArgumentResol
         }
 
         if (annotatedDefaults != null) {
-
             var sort = Sort.unsorted()
-
             for (currentAnnotatedDefault in annotatedDefaults.value) {
                 sort = appendOrCreateSortTo(currentAnnotatedDefault, sort)
             }
-
             return sort
         }
 
@@ -200,15 +195,15 @@ class ReactiveSortHandlerMethodArgumentResolver : SyncHandlerMethodArgumentResol
             val elements = part.split(delimiter.toRegex()).dropLastWhile { it.isEmpty() }.toTypedArray()
 
             val direction = if (elements.isEmpty()) {
-                Optional.empty()
+                null
             } else {
-                Direction.fromOptionalString(elements[elements.size - 1])
+                Direction.fromString(elements[elements.size - 1])
             }
 
-            val lastIndex = direction.map { elements.size - 1 }.orElseGet { elements.size }
+            val lastIndex = direction?.let { elements.size - 1 } ?: elements.size
 
             for (i in 0 until lastIndex) {
-                toOrder(elements[i], direction).ifPresent { allOrders.add(it) }
+                toOrder(elements[i], direction)?.let { allOrders.add(it) }
             }
         }
 
@@ -335,11 +330,11 @@ class ReactiveSortHandlerMethodArgumentResolver : SyncHandlerMethodArgumentResol
         private val SORT_DEFAULTS_NAME = SortDefaults::class.java.simpleName
         private val SORT_DEFAULT_NAME = SortDefault::class.java.simpleName
 
-        private fun toOrder(property: String, direction: Optional<Direction>) =
+        private fun toOrder(property: String, direction: Direction?) =
             if (!StringUtils.hasText(property)) {
-                Optional.empty()
+                null
             } else {
-                Optional.of(direction.map { Order(it, property) }.orElseGet { Order.by(property) })
+                direction?.let { Order(it, property) } ?: Order.by(property)
             }
 
         /**

generators/server/templates/src/main/kotlin/package/config/WebsocketConfiguration.kt.ejs

@@ -38,7 +38,6 @@ import org.springframework.web.socket.server.HandshakeInterceptor
 import org.springframework.web.socket.server.support.DefaultHandshakeHandler
 
 import java.security.Principal
-import java.util.Optional
 
 @Configuration
 @EnableWebSocketMessageBroker
@@ -49,10 +48,9 @@ class WebsocketConfiguration(private val jHipsterProperties: JHipsterProperties)
     }
 
     override fun registerStompEndpoints(registry: StompEndpointRegistry?) {
-        val allowedOrigins =
-            Optional.ofNullable(jHipsterProperties.cors.allowedOrigins)
-                .map { origins -> origins.toTypedArray() }
-                .orElse(arrayOfNulls(0))
+        val allowedOrigins = jHipsterProperties.cors.allowedOrigins
+            ?.let { origins -> origins.toTypedArray() }
+            ?: arrayOfNulls(0)
 
         registry!!.addEndpoint("/websocket/tracker")
             .setHandshakeHandler(defaultHandshakeHandler())

generators/server/templates/src/main/kotlin/package/gateway/ratelimiting/RateLimitingFilter.kt.ejs

@@ -119,7 +119,7 @@ class RateLimitingFilter(private val jHipsterProperties: JHipsterProperties) : Z
      * The ID that will identify the limit: the user login or the user IP address.
      */
     private fun getId(httpServletRequest: HttpServletRequest): String =
-        getCurrentUserLogin().orElse(httpServletRequest.remoteAddr)
+        getCurrentUserLogin() ?: httpServletRequest.remoteAddr
 
     companion object {
         const val GATEWAY_RATE_LIMITING_CACHE_NAME = "gateway-rate-limiting"

generators/server/templates/src/main/kotlin/package/repository/PersistentTokenRepository.kt.ejs

@@ -42,7 +42,6 @@ import javax.validation.Validator
 <%_ } _%>
 <%_ if (databaseType === 'cassandra' || databaseType === 'couchbase') { _%>
 
-import java.util.Optional
 <%_ } _%>
 <%_ if (databaseType === 'couchbase') { _%>
 
@@ -60,7 +59,7 @@ import <%=packageName%>.config.ID_DELIMITER
  */<% } %><% if (databaseType === 'sql' || databaseType === 'mongodb' || databaseType === 'couchbase') { %>
 interface PersistentTokenRepository : <% if (databaseType === 'sql') { %>JpaRepository<% } %><% if (databaseType === 'mongodb') { %>MongoRepository<% } %><% if (databaseType === 'couchbase') { %>N1qlCouchbaseRepository<% } %><PersistentToken, String> {
 <% if (databaseType === 'couchbase') { %>
-    fun findBySeries(series: String): Optional<PersistentToken> {
+    fun findBySeries(series: String): PersistentToken? {
         return findById(PersistentToken.PREFIX + ID_DELIMITER + series)
     }
 
@@ -102,8 +101,7 @@ class PersistentTokenRepository (private val session: Session, private val valid
         "DELETE FROM persistent_token_by_user WHERE user_id = :user_id AND persistent_token_series = :persistent_token_series"
     )
 
-    fun findById(presentedSeries: String): Optional<PersistentToken> =
-        Optional.ofNullable(mapper.get(presentedSeries))
+    fun findById(presentedSeries: String): PersistentToken? = mapper.get(presentedSeries)
 
     fun findByUser( user: <%= asEntity('User') %>): MutableList<PersistentToken> {
         val stmt = findPersistentTokenSeriesByUserIdStmt.bind()