src/main/java/net/pterodactylus/sone/database/memory/MemoryBookmarkDatabase.java

   1 package net.pterodactylus.sone.database.memory;
   2
   3 import static com.google.common.collect.FluentIterable.from;
   4
   5 import java.util.HashSet;
   6 import java.util.Set;
   7 import java.util.concurrent.locks.ReadWriteLock;
   8 import java.util.concurrent.locks.ReentrantReadWriteLock;
   9
  10 import net.pterodactylus.sone.data.Post;
  11 import net.pterodactylus.sone.database.BookmarkDatabase;
  12
  13 import com.google.common.base.Function;
  14
  15 /**
  16  * Memory-based {@link BookmarkDatabase} implementation.
  17  *
  18  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  19  */
  20 public class MemoryBookmarkDatabase implements BookmarkDatabase {
  21
  22         private final ReadWriteLock lock = new ReentrantReadWriteLock();
  23         private final MemoryDatabase memoryDatabase;
  24         private final Set<String> bookmarkedPosts = new HashSet<String>();
  25
  26         public MemoryBookmarkDatabase(MemoryDatabase memoryDatabase) {
  27                 this.memoryDatabase = memoryDatabase;
  28         }
  29
  30         @Override
  31         public void bookmarkPost(String postId) {
  32                 lock.writeLock().lock();
  33                 try {
  34                         bookmarkedPosts.add(postId);
  35                 } finally {
  36                         lock.writeLock().unlock();
  37                 }
  38         }
  39
  40         @Override
  41         public void bookmarkPost(Post post) {
  42                 lock.writeLock().lock();
  43                 try {
  44                         bookmarkedPosts.add(post.getId());
  45                 } finally {
  46                         lock.writeLock().unlock();
  47                 }
  48         }
  49
  50         @Override
  51         public void unbookmarkPost(Post post) {
  52                 lock.writeLock().lock();
  53                 try {
  54                         bookmarkedPosts.remove(post.getId());
  55                 } finally {
  56                         lock.writeLock().unlock();
  57                 }
  58         }
  59
  60         @Override
  61         public boolean isPostBookmarked(Post post) {
  62                 lock.readLock().lock();
  63                 try {
  64                         return bookmarkedPosts.contains(post.getId());
  65                 } finally {
  66                         lock.readLock().unlock();
  67                 }
  68         }
  69
  70         @Override
  71         public Set<Post> getBookmarkedPosts() {
  72                 lock.readLock().lock();
  73                 try {
  74                         return from(bookmarkedPosts).transformAndConcat(
  75                                         new Function<String, Iterable<Post>>() {
  76                                                 @Override
  77                                                 public Iterable<Post> apply(String postId) {
  78                                                         return memoryDatabase.getPost(postId).asSet();
  79                                                 }
  80                                         }).toSet();
  81                 } finally {
  82                         lock.readLock().unlock();
  83                 }
  84         }
  85
  86 }