ConcurrentLinkedHashMap as a cache for stored regions.

amorphine · Nov 24, 2016 · 005e91d · 005e91d
1 parent f072508
commit 005e91d
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Showing 3 changed files with 31 additions and 10 deletions.
diff --git a/pom.xml b/pom.xml
@@ -30,13 +30,18 @@
             <scope>test</scope>
         </dependency>
 
-        <!-- https://mvnrepository.com/artifact/org.ini4j/ini4j -->
         <dependency>
             <groupId>org.ini4j</groupId>
             <artifactId>ini4j</artifactId>
             <version>0.5.1</version>
         </dependency>
 
+        <dependency>
+            <groupId>com.googlecode.concurrentlinkedhashmap</groupId>
+            <artifactId>concurrentlinkedhashmap-lru</artifactId>
+            <version>1.4.2</version>
+        </dependency>
+
 
     </dependencies>
 

diff --git a/src/main/java/ru/wpstuio/amorphine/mcaliases/Region.java b/src/main/java/ru/wpstuio/amorphine/mcaliases/Region.java
@@ -4,13 +4,15 @@
 import com.mojang.nbt.CompoundTag;
 import com.mojang.nbt.NbtIo;
 import net.minecraft.world.level.chunk.storage.RegionFile;
+import org.apache.commons.collections4.map.LRUMap;
 
 import java.io.DataInputStream;
 
 /**
  * Created by amorphine on 21.11.16.
  */
 public class Region {
+
     private Chunk chunks[][] = new Chunk[32][32];
 
     public Region(RegionFile region_file) {

diff --git a/src/main/java/ru/wpstuio/amorphine/mcaliases/World.java b/src/main/java/ru/wpstuio/amorphine/mcaliases/World.java
@@ -1,24 +1,28 @@
 package ru.wpstuio.amorphine.mcaliases;
 
+import com.googlecode.concurrentlinkedhashmap.ConcurrentLinkedHashMap;
 import net.minecraft.world.level.chunk.storage.RegionFile;
 
-import java.io.DataInputStream;
-import java.io.DataOutputStream;
 import java.io.File;
 import java.io.IOException;
-import java.util.ArrayList;
 import java.util.HashMap;
+import java.util.concurrent.ConcurrentMap;
 
 /**
  * Created by amorphine on 21.11.16.
  */
 public class World {
+
     private File world_dir;
 
-    private HashMap region_files = new HashMap<int[], File>();
-    private HashMap regions = new HashMap<int[], Region>();
+    private HashMap<int[], RegionFile> region_files = new HashMap<int[], RegionFile>();
+
+    private ConcurrentMap<int[], Region> regions = new ConcurrentLinkedHashMap.Builder<int[], Region>()
+            .maximumWeightedCapacity(2)
+            .build();
 
     public World(File world_dir) throws IOException {
+
         this.world_dir = world_dir;
         if (!world_dir.exists()) {
             throw new IOException("Cannot access " + world_dir.getAbsolutePath() + ": No such file or directory");
@@ -27,7 +31,9 @@ public World(File world_dir) throws IOException {
         String[] file_list = world_dir.list();
         for(String file_name: file_list) {
             if (file_name.endsWith(".mca")) {
+
                 String[] splitted_file_name = file_name.split("\\.");
+
                 if (splitted_file_name.length < 4) {
                     continue;
                 }
@@ -39,13 +45,21 @@ public World(File world_dir) throws IOException {
                         Integer.parseInt(splitted_file_name[1]),
                         Integer.parseInt(splitted_file_name[2])
                 };
-                region_files.put(cords, region_file);
 
-                RegionFile rg_file = new RegionFile(region_file);
-                Region region = new Region(rg_file);
-                regions.put(cords, region);
+                region_files.put(cords, new RegionFile(region_file));
             }
         }
     }
+    public Region getRegion(int x, int z) {
+        int[] coords = {x, z};
+
+        if(regions.containsKey(coords)) {
+            return  regions.get(coords);
+        } else {
+            Region region = new Region(region_files.get(coords));
+            regions.put(coords, region);
 
+            return region;
+        }
+    }
 }