List authors along with their books

Author: ajaycode

JPATableJoins/src/main/kotlin/com/hello/bookinventory/controller/BookController.kt

@@ -46,6 +46,7 @@ class BookController {
 
     //curl http://localhost:8080/deleteBook
     // Deletes a random book from the book table
+    // Will not delete the author from the author table as orphanRemoval = false
     @RequestMapping ("/deleteBook")
     fun deleteBook () : String {
         val returnTriple  =  bookService.deleteBook ()
@@ -64,4 +65,37 @@ class BookController {
     fun updateBook (): String {
         return bookService.updateBook()
     }
+
+    //curl http://localhost:8080/listAuthors
+    @RequestMapping ("/listAuthors")
+    fun listAuthors (): String {
+        val authorList : List<Author> = bookService.findAllAuthors()
+        var outputString : String = ""
+        for (author in authorList)
+        {
+            val bookList : List<Book> = author.bookList
+
+            if (bookList.isNotEmpty()) {
+                logger.info (bookList.toString())
+                outputString += "[${author.name} wrote ${bookList.toString()}]\n "
+            }
+        }
+        return outputString
+    }
+
+    //curl http://localhost:8080/deleteAuthor
+    // Deletes a random author from the author table
+    // Will not delete the author's book from the book table as orphanRemoval = false
+   /* @RequestMapping ("/deleteAuthor")
+    fun deleteAuthor () : String {
+        val returnTriple  =  bookService.deleteAuthor ()
+        if (returnTriple.first == true)
+        {
+            return "Author # ${returnTriple.second} named ${returnTriple.third} was deleted"
+        }
+        else {
+            return "Author could not be deleted."
+        }
+    }*/
+
 }

JPATableJoins/src/main/kotlin/com/hello/bookinventory/model/Author.kt

@@ -10,7 +10,7 @@ data class Author (
 
     var name : String = "",
 
-    @OneToMany(cascade = arrayOf(CascadeType.ALL), mappedBy = "author", orphanRemoval = false)
+    @OneToMany(mappedBy = "author", orphanRemoval = false)
     var bookList : List<Book> = mutableListOf()
 ){
     override fun toString(): String {

JPATableJoins/src/main/kotlin/com/hello/bookinventory/service/BookService.kt

@@ -91,14 +91,47 @@ class BookService {
         else {
             return ("Title was not updated")
         }
+    }
 
 
+    fun findAllAuthors () : List<Author> {
+        val authors = authorRepository.findAll()
+        for (author in authors){
+            logger.info (author.name)
+        }
+        return authors
 
     }
 
-    fun findAllAuthors () : List <Author> {
-        return authorRepository.findAll()
-    }
+    /*fun deleteAuthor () : KotlinTriple<Boolean, Long, String> {
+        val authorCount = authorRepository.count()
+        val authorToDelete : Long = Random.nextLong(1, authorCount)
+        logger.info ("Will attempt to delete author # $authorToDelete")
+        if (authorRepository.existsById(authorToDelete))
+        {
+            val author  = authorRepository.findById(authorToDelete)
+            var name : String = ""
+            if (author.isPresent())
+                name = author.get().name
+            logger.info ("Title of author to be deleted : ${name}")
+            var status : Boolean = true
+            val bookList = authorRepository.getBookListById(authorToDelete)
+            if (bookList.isNotEmpty())
+                logger.info ("Author has written ${bookList.size} books.")
+            try {
+                authorRepository.deleteById(authorToDelete)
+            }
+            catch (e: Exception)
+            {
+                logger.error("Unable to delete author # $authorToDelete, named ${name} .")
+                logger.error ("Exception thrown. ${e.message}")
+                status = false
+            }
+            if (status == true)
+                return KotlinTriple(true, second = authorToDelete, third = name)
+        }
+        return KotlinTriple(false, second = 0L, third = "null")
+    }*/
 
     fun findBooksByAuthor () : List <Book> {
         TODO ()