Implemented Search Book Functionality

src/main/java/com/libraryman_api/book/BookController.java

@@ -1,6 +1,8 @@
 package com.libraryman_api.book;
 
 import com.libraryman_api.exception.ResourceNotFoundException;
+
+
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.data.domain.Page;
 import org.springframework.data.domain.PageRequest;
@@ -100,4 +102,21 @@ public BookDto updateBook(@PathVariable int id, @RequestBody BookDto bookDtoDeta
     public void deleteBook(@PathVariable int id) {
         bookService.deleteBook(id);
     }
+
+    /**
+     * Searches book based on title, author, genre, etc.
+     * It uses a keyword parameter to filter the books, and pagination is applied to the search results.
+     * If no book is found it will return 204(No content found) http response.
+     * If keyword is null then it will return all books.
+     * @param keyword the Keyword to search Book
+     * @param pageable
+     * @return
+     */
+    @GetMapping("/search")
+    public ResponseEntity<Page<Book>> searchBook(@RequestParam String keyword, @PageableDefault(page = 0, size = 5, sort = "title") Pageable pageable){
+    	Page<Book> books=bookService.searchBook(keyword,pageable);
+    	if(!books.isEmpty())
+    		return ResponseEntity.ok(books);
+    	return ResponseEntity.noContent().build();
+    }
 }

src/main/java/com/libraryman_api/book/BookRepository.java

@@ -1,10 +1,33 @@
 package com.libraryman_api.book;
 
+import org.springframework.data.domain.Page;
+import org.springframework.data.domain.Pageable;
 import org.springframework.data.jpa.repository.JpaRepository;
+import org.springframework.data.jpa.repository.Query;
+import org.springframework.data.repository.query.Param;
 import org.springframework.stereotype.Repository;
 
 @Repository
 public interface BookRepository extends JpaRepository<Book, Integer> {
+
+	/**
+	 * This method use SQL Query for finding book based on
+	 * title, author, genre, publishedYear, etc. By using LIKE operator
+	 * it search from database based on keyword entered.
+	 * 
+	 * @param keyword
+	 * @param pageable
+	 * @return
+	 */
+
+	@Query("SELECT b FROM Book b WHERE "
+	        + "(LOWER(b.title) LIKE LOWER(CONCAT('%', :keyword, '%')) OR "
+	        + "LOWER(b.author) LIKE LOWER(CONCAT('%', :keyword, '%')) OR "
+	        + "LOWER(b.publisher) LIKE LOWER(CONCAT('%', :keyword, '%')) OR "
+	        + "LOWER(b.genre) LIKE LOWER(CONCAT('%', :keyword, '%')) OR "
+	        + "CAST(b.publishedYear AS string) LIKE %:keyword% OR "
+	        + "CAST(b.copiesAvailable AS string) LIKE %:keyword%)")
+	Page<Book> searchBook(@Param("keyword") String keyword,Pageable pageable);
 }
 
 

src/main/java/com/libraryman_api/book/BookService.java

@@ -181,4 +181,16 @@ public Book DtoToEntity(BookDto bookDto) {
         book.setIsbn(bookDto.getIsbn());
         return book;
     }
+
+    /**
+     * <p>This method takes String keyword and search book based on 
+     * title, author, genre, publishedYear, etc. from Book Entity. </p>
+     * 
+     * @param keyword
+     * @param pageable
+     * @return
+     */
+    public Page<Book> searchBook(String keyword,Pageable pageable ){
+    	return bookRepository.searchBook(keyword,pageable);
+    }
 }