+

Author: tsiupa-coder

src/main/java/com/example/controller/BookController.java

@@ -23,7 +23,7 @@ public class BookController {
     @Inject
     private BookService service;
 
-    @Get
+    @Get("/dto")
     public List<BookDTO> books() {
         return service.findAll();
     }
@@ -43,6 +43,11 @@ public Long count() {
         return service.countBooks();
     }
 
+    @Get("/pages")
+    public Long pages(){
+        return service.sumPages();
+    }
+
     @Post
     public HttpMessage create(Book book) {
         service.create(book);

src/main/java/com/example/controller/api/URlConstants.java

@@ -0,0 +1,14 @@
+package com.example.controller.api;
+
+public final class URlConstants {
+
+    public URlConstants() throws IllegalAccessException {
+        throw new IllegalAccessException("it is just for constants");
+    }
+
+    private static final String BOOKS = "books";
+    private static final String TITLE = "title";
+    private static final String MODEL = "model";
+    private static final String INIT = "init";
+    private static final String COUNT = "count";
+    }

src/main/java/com/example/repository/BookRepository.java

@@ -10,6 +10,7 @@
 import io.micronaut.data.repository.CrudRepository;
 
 import java.util.List;
+import java.util.Optional;
 
 @Repository
 public interface BookRepository extends CrudRepository<Book, Long>, JpaSpecificationExecutor<Book> {
@@ -24,5 +25,9 @@ public interface BookRepository extends CrudRepository<Book, Long>, JpaSpecifica
     @EntityGraph(attributePaths = {"author", "title"})
     List<Book> findAll();
 
+    Optional<Integer> findPagesById(Long id);
+
+    Long findSumPages();
+
     List<BookDTO> find();
 }

src/main/java/com/example/service/BookService.java

@@ -11,6 +11,7 @@
 import java.util.List;
 import java.util.NoSuchElementException;
 import java.util.Optional;
+import java.util.stream.Collectors;
 
 @Primary
 @Singleton
@@ -60,6 +61,24 @@ public Book fall() {
 
     }
 
+    @Transactional
+    public Long totalPages(List<Long> id){
+
+        return id.stream()
+                .map(this::getPages)
+                .collect(Collectors.summarizingLong(Integer::intValue))
+                .getCount();
+    }
+
+    @Transactional
+    public Integer getPages(Long bookId){
+        return repository.findPagesById(bookId).orElse(0);
+    }
+
+    @Transactional
+    public Long sumPages(){
+        return repository.findSumPages();
+    }
     @Transactional
     public void create(Book book) {
         repository.save(book);

src/main/resources/db/liquibase-changelog.xml

@@ -78,5 +78,4 @@
         </sql>
     </changeSet>
 
-
 </databaseChangeLog>