feat: implement password update endpoint with DTO and exception handling

src/main/java/com/libraryman_api/exception/GlobalExceptionHandler.java

@@ -9,42 +9,64 @@
 import java.util.Date;
 
 /**
- * Global exception handler for the LibraryMan API.
- * This class provides centralized exception handling across all controllers in the application.
- * It handles specific exceptions and returns appropriate HTTP responses.
+ * Global exception handler for the LibraryMan API. This class provides
+ * centralized exception handling across all controllers in the application. It
+ * handles specific exceptions and returns appropriate HTTP responses.
  */
 @ControllerAdvice
 public class GlobalExceptionHandler {
 
-    /**
-     * Handles {@link ResourceNotFoundException} exceptions.
-     * This method is triggered when a {@code ResourceNotFoundException} is thrown in the application.
-     * It constructs an {@link ErrorDetails} object containing the exception details and returns
-     * a {@link ResponseEntity} with an HTTP status of {@code 404 Not Found}.
-     *
-     * @param ex the exception that was thrown.
-     * @param request the current web request in which the exception was thrown.
-     * @return a {@link ResponseEntity} containing the {@link ErrorDetails} and an HTTP status of {@code 404 Not Found}.
-     */
-    @ExceptionHandler(ResourceNotFoundException.class)
-    public ResponseEntity<?> resourceNotFoundException(ResourceNotFoundException ex, WebRequest request) {
-        ErrorDetails errorDetails = new ErrorDetails(new Date(), ex.getMessage(), request.getDescription(false));
-        return new ResponseEntity<>(errorDetails, HttpStatus.NOT_FOUND);
-    }
-
-    /**
-     * Handles {@link InvalidSortFieldException} exceptions.
-     * This method is triggered when an {@code InvalidSortFieldException} is thrown in the application.
-     * It constructs an {@link ErrorDetails} object containing the exception details and returns
-     * a {@link ResponseEntity} with an HTTP status of {@code 400 Bad Request}.
-     *
-     * @param ex      the exception that was thrown.
-     * @param request the current web request in which the exception was thrown.
-     * @return a {@link ResponseEntity} containing the {@link ErrorDetails} and an HTTP status of {@code 400 Bad Request}.
-     */
-    @ExceptionHandler(InvalidSortFieldException.class)
-    public ResponseEntity<?> invalidSortFieldException(InvalidSortFieldException ex, WebRequest request) {
-        ErrorDetails errorDetails = new ErrorDetails(new Date(), ex.getMessage(), request.getDescription(false));
-        return new ResponseEntity<>(errorDetails, HttpStatus.BAD_REQUEST);
-    }
+	/**
+	 * Handles {@link ResourceNotFoundException} exceptions. This method is
+	 * triggered when a {@code ResourceNotFoundException} is thrown in the
+	 * application. It constructs an {@link ErrorDetails} object containing the
+	 * exception details and returns a {@link ResponseEntity} with an HTTP status of
+	 * {@code 404 Not Found}.
+	 *
+	 * @param ex      the exception that was thrown.
+	 * @param request the current web request in which the exception was thrown.
+	 * @return a {@link ResponseEntity} containing the {@link ErrorDetails} and an
+	 *         HTTP status of {@code 404 Not Found}.
+	 */
+	@ExceptionHandler(ResourceNotFoundException.class)
+	public ResponseEntity<?> resourceNotFoundException(ResourceNotFoundException ex, WebRequest request) {
+		ErrorDetails errorDetails = new ErrorDetails(new Date(), ex.getMessage(), request.getDescription(false));
+		return new ResponseEntity<>(errorDetails, HttpStatus.NOT_FOUND);
+	}
+
+	/**
+	 * Handles {@link InvalidSortFieldException} exceptions. This method is
+	 * triggered when an {@code InvalidSortFieldException} is thrown in the
+	 * application. It constructs an {@link ErrorDetails} object containing the
+	 * exception details and returns a {@link ResponseEntity} with an HTTP status of
+	 * {@code 400 Bad Request}.
+	 *
+	 * @param ex      the exception that was thrown.
+	 * @param request the current web request in which the exception was thrown.
+	 * @return a {@link ResponseEntity} containing the {@link ErrorDetails} and an
+	 *         HTTP status of {@code 400 Bad Request}.
+	 */
+	@ExceptionHandler(InvalidSortFieldException.class)
+	public ResponseEntity<?> invalidSortFieldException(InvalidSortFieldException ex, WebRequest request) {
+		ErrorDetails errorDetails = new ErrorDetails(new Date(), ex.getMessage(), request.getDescription(false));
+		return new ResponseEntity<>(errorDetails, HttpStatus.BAD_REQUEST);
+	}
+
+	/**
+	 * Handles {@link InvalidPasswordException} exceptions. This method is triggered
+	 * when an {@code InvalidPasswordException} is thrown in the application. It
+	 * constructs an {@link ErrorDetails} object containing the exception details
+	 * and returns a {@link ResponseEntity} with an HTTP status of
+	 * {@code 400 Bad Request}.
+	 *
+	 * @param ex      the exception that was thrown.
+	 * @param request the current web request in which the exception was thrown.
+	 * @return a {@link ResponseEntity} containing the {@link ErrorDetails} and an
+	 *         HTTP status of {@code 400 Bad Request}.
+	 */
+	@ExceptionHandler(InvalidPasswordException.class)
+	public ResponseEntity<?> invalidPasswordException(InvalidPasswordException ex, WebRequest request) {
+		ErrorDetails errorDetails = new ErrorDetails(new Date(), ex.getMessage(), request.getDescription(false));
+		return new ResponseEntity<>(errorDetails, HttpStatus.BAD_REQUEST);
+	}
 }

src/main/java/com/libraryman_api/exception/InvalidPasswordException.java

@@ -0,0 +1,50 @@
+package com.libraryman_api.exception;
+
+import java.io.Serial;
+
+/**
+ * Custom exception class to handle scenarios where an invalid password is provided
+ * in the Library Management System. This exception is thrown when a password update
+ * operation fails due to invalid password criteria.
+ */
+public class InvalidPasswordException extends RuntimeException {
+
+    /**
+     * The {@code serialVersionUID} is a unique identifier for each version of a serializable class.
+     * It is used during the deserialization process to verify that the sender and receiver of a
+     * serialized object have loaded classes for that object that are compatible with each other.
+     *
+     * The {@code serialVersionUID} field is important for ensuring that a serialized class
+     * (especially when transmitted over a network or saved to disk) can be successfully deserialized,
+     * even if the class definition changes in later versions. If the {@code serialVersionUID} does not
+     * match during deserialization, an {@code InvalidClassException} is thrown.
+     *
+     * This field is optional, but it is good practice to explicitly declare it to prevent
+     * automatic generation, which could lead to compatibility issues when the class structure changes.
+     *
+     * The {@code @Serial} annotation is used here to indicate that this field is related to
+     * serialization. This annotation is available starting from Java 14 and helps improve clarity
+     * regarding the purpose of this field.
+     */
+    @Serial
+    private static final long serialVersionUID = 1L;
+
+    /**
+     * Constructs a new {@code InvalidPasswordException} with the specified detail message.
+     *
+     * @param message the detail message explaining the reason for the exception
+     */
+    public InvalidPasswordException(String message) {
+        super(message);
+    }
+
+    /**
+     * Constructs a new {@code InvalidPasswordException} with the specified detail message and cause.
+     *
+     * @param message the detail message explaining the reason for the exception
+     * @param cause   the cause of the exception (which is saved for later retrieval by the {@link #getCause()} method)
+     */
+    public InvalidPasswordException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/com/libraryman_api/member/MemberController.java

@@ -99,4 +99,21 @@ public MembersDto updateMember(@PathVariable int id, @RequestBody UpdateMembersD
     public void deleteMember(@PathVariable int id) {
         memberService.deleteMember(id);
     }
+
+    /**
+     * Updates the password for a library member.
+     * If the member is not found or the update fails, an appropriate exception will be thrown.
+     *
+     * @param id the ID of the member whose password is to be updated
+     * @param updatePasswordDto the {@link UpdatePasswordDto} object containing the password details
+     * @return a {@link ResponseEntity} containing a success message indicating the password was updated successfully
+     */
+    @PutMapping("/{id}/password")
+    @PreAuthorize("#id == authentication.principal.memberId")
+    public ResponseEntity<?> updatePassword(@PathVariable int id, 
+                                             @RequestBody UpdatePasswordDto updatePasswordDto) {
+        memberService.updatePassword(id, updatePasswordDto);
+        return ResponseEntity.ok("Password updated successfully.");
+    }
+
 }

src/main/java/com/libraryman_api/member/MemberService.java

@@ -9,9 +9,11 @@
 import org.springframework.data.mapping.PropertyReferenceException;
 import org.springframework.stereotype.Service;
 
+import com.libraryman_api.exception.InvalidPasswordException;
 import com.libraryman_api.exception.InvalidSortFieldException;
 import com.libraryman_api.exception.ResourceNotFoundException;
 import com.libraryman_api.notification.NotificationService;
+import com.libraryman_api.security.config.PasswordEncoder;
 
 
 
@@ -35,16 +37,18 @@ public class MemberService {
 
     private final MemberRepository memberRepository;
     private final NotificationService notificationService;
+    private final PasswordEncoder passwordEncoder;
 
     /**
      * Constructs a new {@code MemberService} with the specified repositories and services.
      *
      * @param memberRepository the repository for managing member records
      * @param notificationService the service for sending notifications related to member activities
      */
-    public MemberService(MemberRepository memberRepository, NotificationService notificationService) {
+    public MemberService(MemberRepository memberRepository, NotificationService notificationService, PasswordEncoder passwordEncoder) {
         this.memberRepository = memberRepository;
         this.notificationService = notificationService;
+        this.passwordEncoder = passwordEncoder;
     }
 
     /**
@@ -143,6 +147,39 @@ public void deleteMember(int memberId) {
         memberRepository.delete(member);
     }
 
+    /**
+     * Updates the password for a library member.
+     *
+     * <p>This method verifies the current password provided by the member, checks if the 
+     * new password is different, and then updates the member's password in the database. 
+     * If the current password is incorrect or the new password is the same as the current 
+     * password, an {@link InvalidPasswordException} is thrown.</p>
+     *
+     * @param memberId the ID of the member whose password is to be updated
+     * @param updatePasswordDto the {@link UpdatePasswordDto} object containing the password details
+     * @throws ResourceNotFoundException if the member with the specified ID is not found
+     * @throws InvalidPasswordException if the current password is incorrect or the new password is the same as the current password
+     */
+    public void updatePassword(int memberId, UpdatePasswordDto updatePasswordDto) {
+        Members member = memberRepository.findById(memberId)
+                .orElseThrow(() -> new ResourceNotFoundException("Member not found"));
+
+        // Check the current password
+        String currentAuthPassword = member.getPassword(); 
+
+        if (!passwordEncoder.bCryptPasswordEncoder().matches(updatePasswordDto.getCurrentPassword(), currentAuthPassword)) {
+            throw new InvalidPasswordException("Current password is incorrect");
+        }
+
+        // Check if new password is different from old password
+        if (updatePasswordDto.getCurrentPassword().equals(updatePasswordDto.getNewPassword())) {
+            throw new InvalidPasswordException("New password must be different from the old password");
+        }
+
+        member.setPassword(passwordEncoder.bCryptPasswordEncoder().encode(updatePasswordDto.getNewPassword()));
+        memberRepository.save(member);
+    }
+
     /**
      * Converts a MembersDto object to a Members entity.
      *

src/main/java/com/libraryman_api/member/UpdatePasswordDto.java

@@ -0,0 +1,40 @@
+package com.libraryman_api.member;
+
+public class UpdatePasswordDto {
+
+    private String currentPassword;
+
+    private String newPassword;
+
+    public UpdatePasswordDto(String currentPassword, String newPassword) {
+		this.currentPassword = currentPassword;
+		this.newPassword = newPassword;
+	}
+
+    public UpdatePasswordDto() {
+    }
+
+    public String getCurrentPassword() {
+		return currentPassword;
+	}
+
+	public void setCurrentPassword(String currentPassword) {
+		this.currentPassword = currentPassword;
+	}
+
+	public String getNewPassword() {
+		return newPassword;
+	}
+
+	public void setNewPassword(String newPassword) {
+		this.newPassword = newPassword;
+	}
+
+	@Override
+    public String toString() {
+        return "UpdatePasswordDto{" +
+        "currentPassword='" + currentPassword + '\'' +
+        ", newPassword='" + newPassword + '\'' +
+        '}';
+    }
+}