Custom annotations and exception handling

src/main/java/com/linkurlshorter/urlshortener/link/EndTimeLinkValidator.java

@@ -0,0 +1,44 @@
+package com.linkurlshorter.urlshortener.link;
+
+
+import jakarta.validation.Constraint;
+import jakarta.validation.Payload;
+
+import java.lang.annotation.*;
+
+/**
+ * The {@link EndTimeLinkValidator} annotation is used to validate the link's end time.
+ * This annotation can be applied to fields, methods, or other annotations.
+ * It uses the UrlShortValidatorImpl implementation to perform the validation.
+ *
+ * @author Vlas Pototskyi
+ */
+@Documented
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ElementType.FIELD, ElementType.METHOD, ElementType.ANNOTATION_TYPE})
+@Constraint(validatedBy = UrlShortValidatorImpl.class)
+public @interface EndTimeLinkValidator {
+
+    /**
+     * The message to be used to inform about the failed validation.
+     * Default: "Link time is not valid!".
+     *
+     * @return Error message.
+     */
+    String message() default "Link time is not valid!";
+
+    /**
+     * Groups to which this constraint belongs. Default: empty array.
+     *
+     * @return Constraint groups.
+     */
+    Class<?>[] groups() default {};
+
+    /**
+     * Parameters that can be used to configure the constraint.
+     * Default: an empty array.
+     *
+     * @return The parameters of the constraint.
+     */
+    Class<? extends Payload>[] payload() default {};
+}

src/main/java/com/linkurlshorter/urlshortener/link/EndTimeLinkValidatorImpl.java

@@ -0,0 +1,28 @@
+package com.linkurlshorter.urlshortener.link;
+
+import jakarta.validation.ConstraintValidator;
+import jakarta.validation.ConstraintValidatorContext;
+
+import java.time.LocalDateTime;
+
+/**
+ * The EndTimeLinkValidatorImpl class implements the {@link ConstraintValidator} interface
+ * for annotating an EndTimeLinkValidator. It is used to validate the LocalDateTime value to check
+ * that the time to which the link is valid is correct.
+ *
+ * @author Vlas Pototskyi
+ */
+public class EndTimeLinkValidatorImpl implements ConstraintValidator<EndTimeLinkValidator, LocalDateTime> {
+    /**
+     * Checks if the time to which the reference is valid is greater than the current time.
+     *
+     * @param value   LocalDateTime The value to be validated.
+     * @param context The context to validate.
+     * @return true if the time to which the reference is valid is greater than the current time; false otherwise.
+     */
+    @Override
+    public boolean isValid(LocalDateTime value, ConstraintValidatorContext context) {
+        LocalDateTime currentTime = LocalDateTime.now();
+        return value.isAfter(currentTime);
+    }
+}

src/main/java/com/linkurlshorter/urlshortener/link/Link.java

@@ -50,6 +50,7 @@ public class Link {
     @Column(name = "statistics")
     private int statistics;
     @Column(name = "status")
+    @Builder.Default
     @Enumerated(EnumType.STRING)
-    private LinkStatus status;
+    private LinkStatus status = LinkStatus.ACTIVE;
 }

src/main/java/com/linkurlshorter/urlshortener/link/LinkController.java

@@ -13,10 +13,8 @@
 import org.springframework.web.bind.annotation.*;
 
 import java.time.LocalDateTime;
-import java.util.Comparator;
-import java.util.List;
 import java.util.UUID;
-import java.util.stream.Collectors;
+
 
 /**
  * Controller for Link-related operations such as create, delete, update and get info + statistics
@@ -34,7 +32,9 @@ public class LinkController {
     private final LinkService linkService;
     private final UserService userService;
     private final EntityManager entityManager;
-    private final LinkInfoDtoMapper linkDtoMapper;
+    private final LinkInfoResponseMapper infoResponseMapper;
+
+    private final LinkInfoResponseMapper infoResponseMapper;
 
     /**
      * Controller method for creating a new link.
@@ -137,50 +137,6 @@ public ResponseEntity<LinkModifyingResponse> refreshLink(@RequestParam UUID id)
             throw new ForbiddenException(OPERATION_FORBIDDEN_MSG);
         }
     }
-        //TODO: for info and all-links-info exclude all results of status DELETED!
-    @GetMapping("/info")
-    public ResponseEntity<LinkInfoResponse> getInfoByShortLink(@RequestParam String shortLink) {
-        Link link = linkService.findByShortLink(shortLink);
-        if (doesUserHaveRightsForLinkById(link.getId())) {
-            LinkInfoDto dto = linkDtoMapper.mapLinkToDto(link);
-            LinkInfoResponse response = new LinkInfoResponse(List.of(dto), "ok");
-            return ResponseEntity.ok(response);
-        } else {
-            throw new ForbiddenException(OPERATION_FORBIDDEN_MSG);
-        }
-    }
-
-    @GetMapping("/all-links-info")
-    public ResponseEntity<LinkInfoResponse> getAllLinksForUser() {
-        try {
-            Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
-            User requesterUser = userService.findByEmail(authentication.getName());
-            List<LinkInfoDto> linksDto = linkService
-                    .findAllByUser(requesterUser)
-                    .stream()
-                    .map(linkDtoMapper::mapLinkToDto)
-                    .sorted(Comparator.comparing(LinkInfoDto::getUsageStatistics).reversed())
-                    .collect(Collectors.toList());
-            return ResponseEntity.ok(new LinkInfoResponse(linksDto, "ok"));
-        } catch (Exception e) {
-            throw new InternalServerLinkException();
-        }
-
-    }
-
-    //TODO: exclude all results of non-Active (or only of DELETED?)
-    @GetMapping("/url-usage-top-for-user")
-    public ResponseEntity<LinkStatisticsResponse> getLinksStatsForUser() {
-        try {
-            Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
-            User requesterUser = userService.findByEmail(authentication.getName());
-            List<LinkStatisticsDto> stats = linkService.getLinkUsageStatsByUserId(requesterUser.getId());
-            stats.sort(Comparator.comparing(LinkStatisticsDto::getUsageStatistics).reversed());
-            return ResponseEntity.ok(new LinkStatisticsResponse(stats, "ok"));
-        } catch (Exception e) {
-            throw new InternalServerLinkException();
-        }
-    }
 
     /**
      * Generates a new short link.

src/main/java/com/linkurlshorter/urlshortener/link/LinkInfoResponse.java

@@ -7,6 +7,15 @@
 
 import java.util.List;
 
+/**
+ * Represents a response containing information about a link.
+ * This class provides various properties related to a link, such as its ID, long link,
+ * short link, creation time, expiration time, usage statistics, and status.
+ * Instances of this class can be created using the provided builder pattern.
+ *
+ * @author Artem Poliakov
+ * @version 1.0
+ */
 @Data
 @AllArgsConstructor
 @NoArgsConstructor

src/main/java/com/linkurlshorter/urlshortener/link/LinkInfoResponseMapper.java

@@ -0,0 +1,29 @@
+package com.linkurlshorter.urlshortener.link;
+
+import org.springframework.stereotype.Component;
+
+/**
+ * Mapper class responsible for mapping a Link entity to a LinkInfoResponse object.
+ * <p>
+ * This mapper class provides a method to map a Link entity along with an optional error message
+ * <p>
+ * to a LinkInfoResponse object.
+ *
+ * @author Artem Poliakov
+ * @version 1.0
+ */
+@Component
+public class LinkInfoResponseMapper {
+    public LinkInfoResponse mapLinkToResponse(Link link, String error) {
+        return LinkInfoResponse.builder()
+                .id(link.getId())
+                .longLink(link.getLongLink())
+                .shortLink(link.getShortLink())
+                .createdTime(link.getCreatedTime())
+                .expirationTime(link.getExpirationTime())
+                .usageStatistics(link.getStatistics())
+                .status(link.getStatus())
+                .error(error)
+                .build();
+    }
+}

src/main/java/com/linkurlshorter/urlshortener/link/LinkRepository.java

@@ -3,13 +3,9 @@
 import com.linkurlshorter.urlshortener.user.User;
 import org.springframework.data.jpa.repository.JpaRepository;
 import org.springframework.stereotype.Repository;
-import org.springframework.data.jpa.repository.Modifying;
 import org.springframework.data.jpa.repository.Query;
 import org.springframework.data.repository.query.Param;
-import org.springframework.transaction.annotation.Transactional;
 
-import java.sql.Timestamp;
-import java.time.LocalDateTime;
 import java.util.List;
 import java.util.Optional;
 import java.util.UUID;
@@ -34,9 +30,10 @@ public interface LinkRepository extends JpaRepository<Link, UUID> {
      */
     Optional<Link> findByShortLink(String shortLink);
 
-    List<Link> findAllByUser(User user);
+    @Query("SELECT l from Link l WHERE l.user.id = :userId AND l.status <> 'DELETED'")
+    List<Link> findAllByUserId(@Param(value = "userId") UUID userId);
 
     @Query("SELECT new com.linkurlshorter.urlshortener.link.LinkStatisticsDto(l.id, l.shortLink, l.statistics)" +
-            " FROM Link l WHERE l.user.id = :userId")
+            " FROM Link l WHERE l.user.id = :userId AND l.status <> 'DELETED'")
     List<LinkStatisticsDto> getLinkUsageStatsForUser(@Param(value = "userId") UUID userId);
 }

src/main/java/com/linkurlshorter/urlshortener/link/LinkService.java

@@ -38,6 +38,7 @@ public Link save(Link link) {
      * @throws NullLinkPropertyException If the 'link' parameter is null.
      * @throws DeletedLinkException      If the link has been marked as deleted.
      */
+
     public Link update(Link link) {
         if (Objects.isNull(link)) {
             throw new NullLinkPropertyException();
@@ -88,19 +89,20 @@ public Link findByShortLink(String shortLink) {
         return link;
     }
 
-    public List<Link> findAllByUser(User user){
-        if(Objects.isNull(user)){
+    public List<Link> findAllByUser(User user) {
+        if (Objects.isNull(user)) {
             throw new NullLinkPropertyException();
         }
-        return linkRepository.findAllByUser(user);
+        return linkRepository.findAllByUserId(userId);
     }
 
-    public List<LinkStatisticsDto> getLinkUsageStatsByUserId(UUID userId){
-        if(Objects.isNull(userId)){
+    public List<LinkStatisticsDto> getLinkUsageStatsByUserId(UUID userId) {
+        if (Objects.isNull(userId)) {
             throw new NullLinkPropertyException();
         }
         return linkRepository.getLinkUsageStatsForUser(userId);
     }
+
     /**
      * Marks a link entity as deleted by its short link.
      *
@@ -125,6 +127,25 @@ public void deleteById(UUID id) {        //TODO: needs test
         linkRepository.deleteById(id);
     }
 
+    /**
+     * Searches for a unique existing link by a short link.
+     * If an active link is found for the specified short link, returns that link.
+     *
+     * @param shortLink A string representing the short link to be searched.
+     * @return The active link found for the specified short link.
+     * @throws NoLinkFoundByShortLinkException If no link was found by the short link.
+     * @throws NullLinkPropertyException       If the found link does not have the ACTIVE status.
+     */
+    public Link findByExistUniqueLink(String shortLink) {
+        Link existingLink = linkRepository.findByShortLink(shortLink).orElseThrow(NoLinkFoundByShortLinkException::new);
+        if (existingLink.getStatus() == LinkStatus.ACTIVE) {
+            return existingLink;
+        } else {
+            throw new NullLinkPropertyException();
+        }
+    }
+
+
     /**
      * Throws a DeletedLinkException if the link has been marked as deleted.
      *
@@ -137,3 +158,4 @@ private void throwIfDeleted(Link link) {
         }
     }
 }
+

src/main/java/com/linkurlshorter/urlshortener/link/LinkStatisticsDto.java

@@ -6,7 +6,13 @@
 import lombok.NoArgsConstructor;
 
 import java.util.UUID;
-
+/**
+ * Data transfer object (DTO) for representing link statistics.
+ * This class encapsulates information about a link's ID, short link, and usage statistics.
+ *
+ * @author Artem Poliakov
+ * @version 1.0
+ */
 @Data
 @AllArgsConstructor
 @NoArgsConstructor

src/main/java/com/linkurlshorter/urlshortener/link/LinkStatisticsResponse.java

@@ -6,7 +6,14 @@
 import lombok.NoArgsConstructor;
 
 import java.util.List;
-
+/**
+ * Data transfer object (DTO) for representing a response containing statistics of links.
+ * This class encapsulates a list of {@link LinkStatisticsDto} objects representing link statistics,
+ * along with an optional error message.
+ *
+ * @author Artem Poliakov
+ * @version 1.0
+ */
 @Data
 @AllArgsConstructor
 @NoArgsConstructor

src/main/java/com/linkurlshorter/urlshortener/link/UrlShortValidator.java

@@ -0,0 +1,40 @@
+package com.linkurlshorter.urlshortener.link;
+
+import jakarta.validation.Constraint;
+import jakarta.validation.Payload;
+
+import java.lang.annotation.*;
+/**
+ * An annotation {@link UrlShortValidator} used to validate short URLs.
+ * Can be applied to fields, methods, or other annotations.
+ * Uses the {@link UrlShortValidatorImpl} implementation to perform the validation.
+ */
+@Documented
+@Retention(RetentionPolicy.RUNTIME)
+@Target({ElementType.FIELD, ElementType.METHOD, ElementType.ANNOTATION_TYPE})
+@Constraint(validatedBy = UrlShortValidatorImpl.class)
+public @interface UrlShortValidator {
+
+    /**
+     * The message to be used to inform about the failed validation.
+     * Default: "".
+     *
+     * @return Error message.
+     */
+    String message() default "";
+
+    /**
+     * Groups to which this constraint belongs. Default: empty array.
+     *
+     * @return Constraint groups.
+     */
+    Class<?>[] groups() default {};
+
+    /**
+     * Parameters that can be used to configure the constraint.
+     * Default: an empty array.
+     *
+     * @return The parameters of the constraint.
+     */
+    Class<? extends Payload>[] payload() default {};
+}