updated the code for exceptions

Author: sumanmathad

src/main/java/com/learn/SpringBootRESTService/LibraryController.java

@@ -9,6 +9,7 @@
 import org.springframework.web.bind.annotation.RequestBody;
 import org.springframework.web.bind.annotation.RestController;
 
+import com.learn.SpringBootRESTService.Service.LibraryService;
 import com.learn.SpringBootRESTService.repository.LibraryRepository;
 
 @RestController
@@ -20,10 +21,14 @@ public class LibraryController {
 	@Autowired
 	AddResponse addResponse;
 
+	@Autowired
+	LibraryService libraryService;
 
 	@PostMapping("/addBook")
 	public ResponseEntity addBookImplementation(@RequestBody Library library) {
-		String id= library.getIsbn()+library.getAisle();
+		String id= libraryService.buildId(library.getIsbn(),library.getAisle());
+		
+		if (!libraryService.checkBookExists(id)) {
 		library.setId(id);
 		repository.save(library);
 		addResponse.setMsg("Success!! Book is added");
@@ -32,6 +37,14 @@ public ResponseEntity addBookImplementation(@RequestBody Library library) {
 		headers.add("Unique-Header", "First");
 		//return addResponse; without response headers!
 		return new ResponseEntity<AddResponse>(addResponse,headers,HttpStatus.CREATED);
+		}
+		else 
+		{
+			addResponse.setMsg("Book Already Exists");
+			addResponse.setId(id);
+			
+			return new ResponseEntity<AddResponse>(addResponse,HttpStatus.ACCEPTED);
+		}
 
 	}
 

src/main/java/com/learn/SpringBootRESTService/Service/LibraryService.java

@@ -0,0 +1,34 @@
+package com.learn.SpringBootRESTService.Service;
+
+import java.util.Optional;
+
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+
+import com.learn.SpringBootRESTService.Library;
+import com.learn.SpringBootRESTService.repository.LibraryRepository;
+@Service
+public class LibraryService {
+	@Autowired
+	LibraryRepository libraryRepository;
+	
+	public String buildId(String isbn, int aisle) {
+		return isbn+aisle;		
+	}
+	
+	public boolean checkBookExists(String id) {
+		
+		Optional<Library> lib = libraryRepository.findById(id);
+		if(lib.isPresent()) {
+			return true;
+		}
+		else {
+			return false;
+		}
+		
+		
+	}
+	
+	
+
+}