Refactor FileDownloadTask

HMCL/src/main/java/org/jackhuang/hmcl/game/HMCLDependencyManager.java

@@ -19,7 +19,7 @@ package org.jackhuang.hmcl.game;
 
 import org.jackhuang.hmcl.download.DefaultDependencyManager;
 import org.jackhuang.hmcl.download.DownloadProvider;
-import org.jackhuang.hmcl.download.GameBuilder;
+import org.jackhuang.hmcl.download.game.GameAssetDownloadTask;
 import org.jackhuang.hmcl.setting.Profile;
 import org.jackhuang.hmcl.task.ParallelTask;
 import org.jackhuang.hmcl.task.Task;
@@ -28,23 +28,15 @@ import org.jackhuang.hmcl.task.Task;
  * @author huangyuhui
  */
 public class HMCLDependencyManager extends DefaultDependencyManager {
-    private final Profile profile;
 
     public HMCLDependencyManager(Profile profile, DownloadProvider downloadProvider) {
         super(profile.getRepository(), downloadProvider);
-
-        this.profile = profile;
-    }
-
-    @Override
-    public GameBuilder gameBuilder() {
-        return new HMCLGameBuilder(profile);
     }
 
     @Override
     public Task checkGameCompletionAsync(Version version) {
         return new ParallelTask(
-                new HMCLGameAssetDownloadTask(this, version),
+                new GameAssetDownloadTask(this, version),
                 new HMCLGameLibrariesTask(this, version)
         );
     }

HMCL/src/main/java/org/jackhuang/hmcl/game/HMCLGameAssetDownloadTask.java

@@ -1,94 +0,0 @@
-/*
- * Hello Minecraft! Launcher.
- * Copyright (C) 2017  huangyuhui <huanghongxun2008@126.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see {http://www.gnu.org/licenses/}.
- */
-package org.jackhuang.hmcl.game;
-
-import org.jackhuang.hmcl.download.AbstractDependencyManager;
-import org.jackhuang.hmcl.task.FileDownloadTask;
-import org.jackhuang.hmcl.task.Task;
-import org.jackhuang.hmcl.util.*;
-
-import java.io.File;
-import java.nio.file.Path;
-import java.util.*;
-
-public class HMCLGameAssetDownloadTask extends Task {
-
-    private final AbstractDependencyManager dependencyManager;
-    private final Version version;
-    private final AssetIndexInfo assetIndexInfo;
-    private final File assetIndexFile;
-    private final List<Task> dependents = new LinkedList<>();
-    private final List<Task> dependencies = new LinkedList<>();
-
-    /**
-     * Constructor.
-     *
-     * @param dependencyManager the dependency manager that can provides {@link GameRepository}
-     * @param version           the <b>resolved</b> version
-     */
-    public HMCLGameAssetDownloadTask(HMCLDependencyManager dependencyManager, Version version) {
-        this.dependencyManager = dependencyManager;
-        this.version = version;
-        this.assetIndexInfo = version.getAssetIndex();
-        this.assetIndexFile = dependencyManager.getGameRepository().getIndexFile(version.getId(), assetIndexInfo.getId());
-
-        if (!assetIndexFile.exists())
-            dependents.add(new HMCLGameAssetIndexDownloadTask(dependencyManager, version));
-    }
-
-    @Override
-    public Collection<Task> getDependents() {
-        return dependents;
-    }
-
-    @Override
-    public Collection<Task> getDependencies() {
-        return dependencies;
-    }
-
-    @Override
-    public void execute() throws Exception {
-        AssetIndex index = Constants.GSON.fromJson(FileUtils.readText(assetIndexFile), AssetIndex.class);
-        int progress = 0;
-        if (index != null)
-            for (AssetObject assetObject : index.getObjects().values()) {
-                if (Thread.interrupted())
-                    throw new InterruptedException();
-
-                File file = dependencyManager.getGameRepository().getAssetObject(version.getId(), assetIndexInfo.getId(), assetObject);
-                if (file.isFile())
-                    HMCLLocalRepository.REPOSITORY.tryCacheAssetObject(assetObject, file.toPath());
-                else {
-                    Optional<Path> path = HMCLLocalRepository.REPOSITORY.getAssetObject(assetObject);
-                    if (path.isPresent()) {
-                        FileUtils.copyFile(path.get().toFile(), file);
-                    } else {
-                        String url = dependencyManager.getDownloadProvider().getAssetBaseURL() + assetObject.getLocation();
-                        FileDownloadTask task = new FileDownloadTask(NetworkUtils.toURL(url), file, new FileDownloadTask.IntegrityCheck("SHA-1", assetObject.getHash()));
-                        task.setName(assetObject.getHash());
-                        dependencies.add(task.finalized((v, succ) -> {
-                            if (succ)
-                                HMCLLocalRepository.REPOSITORY.cacheAssetObject(assetObject, file.toPath());
-                        }));
-                    }
-                }
-
-                updateProgress(++progress, index.getObjects().size());
-            }
-    }
-}

HMCL/src/main/java/org/jackhuang/hmcl/game/HMCLGameAssetIndexDownloadTask.java

@@ -1,73 +0,0 @@
-/*
- * Hello Minecraft! Launcher.
- * Copyright (C) 2017  huangyuhui <huanghongxun2008@126.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see {http://www.gnu.org/licenses/}.
- */
-package org.jackhuang.hmcl.game;
-
-import org.jackhuang.hmcl.task.FileDownloadTask;
-import org.jackhuang.hmcl.task.Task;
-import org.jackhuang.hmcl.util.FileUtils;
-import org.jackhuang.hmcl.util.NetworkUtils;
-
-import java.io.File;
-import java.net.URL;
-import java.nio.file.Path;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Optional;
-
-public class HMCLGameAssetIndexDownloadTask extends Task {
-
-    private final HMCLDependencyManager dependencyManager;
-    private final Version version;
-    private final List<Task> dependencies = new LinkedList<>();
-
-    /**
-     * Constructor.
-     *
-     * @param dependencyManager the dependency manager that can provides {@link org.jackhuang.hmcl.game.GameRepository}
-     * @param version the <b>resolved</b> version
-     */
-    public HMCLGameAssetIndexDownloadTask(HMCLDependencyManager dependencyManager, Version version) {
-        this.dependencyManager = dependencyManager;
-        this.version = version;
-        setSignificance(TaskSignificance.MODERATE);
-    }
-
-    @Override
-    public List<Task> getDependencies() {
-        return dependencies;
-    }
-
-    @Override
-    public void execute() throws Exception {
-        AssetIndexInfo assetIndexInfo = version.getAssetIndex();
-        File assetIndexFile = dependencyManager.getGameRepository().getIndexFile(version.getId(), assetIndexInfo.getId());
-
-        Optional<Path> path = HMCLLocalRepository.REPOSITORY.getAssetIndex(assetIndexInfo);
-        if (path.isPresent()) {
-            FileUtils.copyFile(path.get().toFile(), assetIndexFile);
-        } else {
-            URL url = NetworkUtils.toURL(dependencyManager.getDownloadProvider().injectURL(assetIndexInfo.getUrl()));
-            dependencies.add(new FileDownloadTask(url, assetIndexFile)
-                    .finalized((v, succ) -> {
-                        if (succ)
-                            HMCLLocalRepository.REPOSITORY.cacheAssetIndex(assetIndexInfo, assetIndexFile.toPath());
-                    }));
-        }
-    }
-
-}

HMCL/src/main/java/org/jackhuang/hmcl/game/HMCLGameBuilder.java

@@ -1,40 +0,0 @@
-/*
- * Hello Minecraft! Launcher.
- * Copyright (C) 2018  huangyuhui <huanghongxun2008@126.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see {http://www.gnu.org/licenses/}.
- */
-package org.jackhuang.hmcl.game;
-
-import org.jackhuang.hmcl.download.DefaultGameBuilder;
-import org.jackhuang.hmcl.setting.Profile;
-import org.jackhuang.hmcl.task.Task;
-
-/**
- * @author huangyuhui
- */
-public class HMCLGameBuilder extends DefaultGameBuilder {
-    private final Profile profile;
-
-    public HMCLGameBuilder(Profile profile) {
-        super(profile.getDependency());
-
-        this.profile = profile;
-    }
-
-    @Override
-    protected Task downloadGameAsync(String gameVersion, Version version) {
-        return new HMCLGameDownloadTask(profile, gameVersion, version);
-    }
-}

HMCL/src/main/java/org/jackhuang/hmcl/game/HMCLGameDownloadTask.java

@@ -1,86 +0,0 @@
-/*
- * Hello Minecraft! Launcher.
- * Copyright (C) 2018  huangyuhui <huanghongxun2008@126.com>
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see {http://www.gnu.org/licenses/}.
- */
-package org.jackhuang.hmcl.game;
-
-import org.jackhuang.hmcl.setting.Profile;
-import org.jackhuang.hmcl.task.FileDownloadTask;
-import org.jackhuang.hmcl.task.FileDownloadTask.IntegrityCheck;
-import org.jackhuang.hmcl.task.Task;
-import org.jackhuang.hmcl.util.FileUtils;
-import org.jackhuang.hmcl.util.Logging;
-import org.jackhuang.hmcl.util.NetworkUtils;
-
-import java.io.File;
-import java.io.IOException;
-import java.net.URL;
-import java.nio.file.Path;
-import java.util.Collection;
-import java.util.LinkedList;
-import java.util.List;
-import java.util.Optional;
-import java.util.logging.Level;
-
-/**
- * @author huangyuhui
- */
-public class HMCLGameDownloadTask extends Task {
-    private final Profile profile;
-    private final String gameVersion;
-    private final Version version;
-    private final List<Task> dependencies = new LinkedList<>();
-
-    public HMCLGameDownloadTask(Profile profile, String gameVersion, Version version) {
-        this.profile = profile;
-        this.gameVersion = gameVersion;
-        this.version = version;
-
-        setSignificance(TaskSignificance.MINOR);
-    }
-
-    @Override
-    public Collection<Task> getDependencies() {
-        return dependencies;
-    }
-
-    @Override
-    public void execute() {
-        File jar = profile.getRepository().getVersionJar(version);
-
-        Optional<Path> path = HMCLLocalRepository.REPOSITORY.getVersion(gameVersion, version);
-        if (path.isPresent()) {
-            try {
-                FileUtils.copyFile(path.get().toFile(), jar);
-                return;
-            } catch (IOException e) {
-                Logging.LOG.log(Level.SEVERE, "Unable to copy cached Minecraft jar from " + path.get() + " to " + jar, e);
-            }
-        }
-
-        URL url = NetworkUtils.toURL(profile.getDependency().getDownloadProvider().injectURL(version.getDownloadInfo().getUrl()));
-
-        if (version.getDownloadInfo().getSha1() == null) {
-            // We do not know jar's hash, then we will not cache it.
-            dependencies.add(new FileDownloadTask(url, jar));
-        } else {
-            dependencies.add(new FileDownloadTask(url, jar,
-                    new IntegrityCheck("SHA-1", version.getDownloadInfo().getSha1())
-            ).then(Task.of(v -> HMCLLocalRepository.REPOSITORY.cacheVersion(version, jar.toPath()))));
-        }
-    }
-
-}

HMCL/src/main/java/org/jackhuang/hmcl/game/HMCLLocalRepository.java

@@ -31,14 +31,10 @@ import java.util.*;
 import java.util.logging.Level;
 import java.util.stream.Collectors;
 
-public class HMCLLocalRepository {
+public class HMCLLocalRepository extends LocalRepository {
     private final StringProperty directory = new SimpleStringProperty();
 
-    private Path commonDir;
-    private Path cacheDir;
     private Path librariesDir;
-    private Path jarsDir;
-    private Path assetObjectsDir;
     private Path indexFile;
 
     private Index index = null;
@@ -59,13 +55,12 @@ public class HMCLLocalRepository {
         this.directory.set(directory);
     }
 
-    private void changeDirectory(Path commonDir) {
+    @Override
-        this.commonDir = commonDir;
+    protected void changeDirectory(Path commonDir) {
-        cacheDir = commonDir.resolve("cache");
+        super.changeDirectory(commonDir);
+
         librariesDir = commonDir.resolve("libraries");
-        jarsDir = commonDir.resolve("jars");
+        indexFile = getCacheDirectory().resolve("index.json");
-        assetObjectsDir = commonDir.resolve("assets").resolve("objects");
-        indexFile = cacheDir.resolve("index.json");
 
         try {
             index = Constants.GSON.fromJson(FileUtils.readText(indexFile.toFile()), Index.class);
@@ -75,15 +70,6 @@ public class HMCLLocalRepository {
         }
     }
 
-    private Path getFile(String algorithm, String hash) {
-        return cacheDir.resolve(algorithm).resolve(hash.substring(0, 2)).resolve(hash);
-    }
-
-    private boolean fileExists(String algorithm, String hash) {
-        if (hash == null) return false;
-        return Files.exists(getFile(algorithm, hash));
-    }
-
     /**
      * Try to cache the library given.
      * This library will be cached only if it is verified.
@@ -187,145 +173,6 @@ public class HMCLLocalRepository {
         return cache;
     }
 
-    /**
-     * Get the path of cached asset index file, empty if not cached
-     *
-     * @param info the asset index info
-     * @return the cached path if exists, otherwise empty
-     */
-    public synchronized Optional<Path> getAssetIndex(AssetIndexInfo info) {
-        String hash = info.getSha1();
-
-        if (fileExists(SHA1, hash))
-            return Optional.of(getFile(SHA1, hash));
-
-        // check old common directory
-        Path file = commonDir.resolve("assets").resolve("indexes").resolve(info.getId() + ".json");
-        if (Files.exists(file)) {
-            try {
-                if (hash != null) {
-                    String checksum = Hex.encodeHex(DigestUtils.digest("SHA-1", file));
-                    if (hash.equalsIgnoreCase(checksum))
-                        return Optional.of(restore(file, () -> cacheAssetIndex(info, file)));
-                } else {
-                    return Optional.of(file);
-                }
-            } catch (IOException e) {
-                // we cannot check the hashcode or unable to move file.
-            }
-        }
-
-        return Optional.empty();
-    }
-
-    /**
-     * Caches the asset index file to repository.
-     *
-     * @param assetIndexInfo the asset index of
-     * @param path the file being cached, must be verified
-     * @return cached file location
-     * @throws IOException if failed to calculate hash code of {@code path} or copy the file to cache
-     */
-    public synchronized Path cacheAssetIndex(AssetIndexInfo assetIndexInfo, Path path) throws IOException {
-        String hash = assetIndexInfo.getSha1();
-        if (hash == null)
-            hash = Hex.encodeHex(DigestUtils.digest(SHA1, path));
-
-        Path cache = getFile(SHA1, hash);
-        FileUtils.copyFile(path.toFile(), cache.toFile());
-
-        return cache;
-    }
-
-    public synchronized Optional<Path> getVersion(String gameVersion, Version version) {
-        DownloadInfo info = version.getDownloadInfo();
-        String hash = info.getSha1();
-
-        if (fileExists(SHA1, hash))
-            return Optional.of(getFile(SHA1, hash));
-
-        // check old common directory, but we will no longer maintain it.
-        Path jar = jarsDir.resolve(gameVersion + ".jar");
-        if (Files.exists(jar)) {
-            if (hash != null) {
-                try {
-                    String checksum = Hex.encodeHex(DigestUtils.digest("SHA-1", jar));
-                    if (!checksum.equalsIgnoreCase(hash)) {
-                        // The file is not the one we want
-                        return Optional.empty();
-                    } else {
-                        return Optional.of(restore(jar, () -> cacheVersion(version, jar)));
-                    }
-                } catch (IOException e) {
-                    // we cannot check the hashcode.
-                    return Optional.empty();
-                }
-            } else {
-                return Optional.of(jar);
-            }
-        }
-
-        return Optional.empty();
-    }
-
-    public synchronized Path cacheVersion(Version version, Path path) throws IOException {
-        if (version.getDownloadInfo().getSha1() == null)
-            throw new IllegalStateException();
-
-        Path cache = getFile(SHA1, version.getDownloadInfo().getSha1());
-        FileUtils.copyFile(path.toFile(), cache.toFile());
-        return cache;
-    }
-
-    public synchronized Optional<Path> getAssetObject(AssetObject assetObject) {
-        String hash = assetObject.getHash();
-
-        if (fileExists(SHA1, hash))
-            return Optional.of(getFile(SHA1, hash));
-
-        // check old common directory, but we will no longer maintain it.
-        Path file = assetObjectsDir.resolve(assetObject.getLocation());
-        if (Files.exists(file)) {
-            if (hash != null) {
-                try {
-                    String checksum = Hex.encodeHex(DigestUtils.digest("SHA-1", file));
-                    if (!checksum.equalsIgnoreCase(hash)) {
-                        // The file is not the one we want
-                        return Optional.empty();
-                    } else {
-                        return Optional.of(restore(file, () -> cacheAssetObject(assetObject, file)));
-                    }
-                } catch (IOException e) {
-                    // we cannot check the hashcode.
-                    return Optional.empty();
-                }
-            } else {
-                return Optional.of(file);
-            }
-        }
-
-        return Optional.empty();
-    }
-
-    public synchronized Path cacheAssetObject(AssetObject assetObject, Path path) throws IOException {
-        Path cache = getFile(SHA1, assetObject.getHash());
-        FileUtils.copyFile(path.toFile(), cache.toFile());
-        return cache;
-    }
-
-    public synchronized void tryCacheAssetObject(AssetObject assetObject, Path path) throws IOException {
-        Path cache = getFile(SHA1, assetObject.getHash());
-        if (Files.exists(cache)) return;
-        FileUtils.copyFile(path.toFile(), cache.toFile());
-    }
-
-    private Path restore(Path original, ExceptionalSupplier<Path, ? extends IOException> cacheSupplier) throws IOException {
-        Path cache = cacheSupplier.get();
-        Files.delete(original);
-        Files.createLink(original, cache);
-        return cache;
-    }
-
     private void saveIndex() {
         if (indexFile == null || index == null) return;
         try {

HMCL/src/main/java/org/jackhuang/hmcl/setting/Settings.java

@@ -21,6 +21,7 @@ import javafx.scene.text.Font;
 import org.jackhuang.hmcl.Launcher;
 import org.jackhuang.hmcl.download.DownloadProvider;
 import org.jackhuang.hmcl.game.HMCLLocalRepository;
+import org.jackhuang.hmcl.util.LocalRepository;
 
 import static org.jackhuang.hmcl.setting.ConfigHolder.config;
 
@@ -47,6 +48,7 @@ public class Settings {
         Accounts.init();
         Profiles.init();
 
+        LocalRepository.setInstance(HMCLLocalRepository.REPOSITORY);
         HMCLLocalRepository.REPOSITORY.directoryProperty().bind(config().commonDirectoryProperty());
     }
 

HMCL/src/main/java/org/jackhuang/hmcl/ui/construct/TaskListPane.java

@@ -24,9 +24,9 @@ import javafx.scene.layout.BorderPane;
 import javafx.scene.layout.StackPane;
 import javafx.scene.layout.VBox;
 import org.jackhuang.hmcl.download.forge.ForgeInstallTask;
+import org.jackhuang.hmcl.download.game.GameAssetDownloadTask;
 import org.jackhuang.hmcl.download.liteloader.LiteLoaderInstallTask;
 import org.jackhuang.hmcl.download.optifine.OptiFineInstallTask;
-import org.jackhuang.hmcl.game.HMCLGameAssetDownloadTask;
 import org.jackhuang.hmcl.game.HMCLModpackExportTask;
 import org.jackhuang.hmcl.game.HMCLModpackInstallTask;
 import org.jackhuang.hmcl.mod.*;
@@ -61,7 +61,7 @@ public final class TaskListPane extends StackPane {
                 if (!task.getSignificance().shouldShow())
                     return;
 
-                if (task instanceof HMCLGameAssetDownloadTask) {
+                if (task instanceof GameAssetDownloadTask) {
                     task.setName(i18n("assets.download_all"));
                 } else if (task instanceof ForgeInstallTask) {
                     task.setName(i18n("install.installer.install", i18n("install.installer.forge")));

HMCLCore/src/main/java/org/jackhuang/hmcl/download/DefaultGameBuilder.java

@@ -80,7 +80,7 @@ public class DefaultGameBuilder extends GameBuilder {
     }
 
     protected Task downloadGameAsync(String gameVersion, Version version) {
-        return new GameDownloadTask(dependencyManager, version);
+        return new GameDownloadTask(dependencyManager, gameVersion, version);
     }
 
 }

HMCLCore/src/main/java/org/jackhuang/hmcl/download/game/GameAssetDownloadTask.java

@@ -18,18 +18,21 @@
 package org.jackhuang.hmcl.download.game;
 
 import org.jackhuang.hmcl.download.AbstractDependencyManager;
+import org.jackhuang.hmcl.game.AssetIndex;
+import org.jackhuang.hmcl.game.AssetIndexInfo;
 import org.jackhuang.hmcl.game.AssetObject;
 import org.jackhuang.hmcl.game.Version;
 import org.jackhuang.hmcl.task.FileDownloadTask;
-import org.jackhuang.hmcl.task.FileDownloadTask.IntegrityCheck;
 import org.jackhuang.hmcl.task.Task;
+import org.jackhuang.hmcl.util.Constants;
 import org.jackhuang.hmcl.util.FileUtils;
-import org.jackhuang.hmcl.util.Logging;
+import org.jackhuang.hmcl.util.LocalRepository;
 import org.jackhuang.hmcl.util.NetworkUtils;
 
 import java.io.File;
-import java.util.*;
+import java.util.Collection;
-import java.util.logging.Level;
+import java.util.LinkedList;
+import java.util.List;
 
 /**
  *
@@ -39,7 +42,9 @@ public final class GameAssetDownloadTask extends Task {
     
     private final AbstractDependencyManager dependencyManager;
     private final Version version;
-    private final GameAssetRefreshTask refreshTask;
+    private final AssetIndexInfo assetIndexInfo;
+    private final File assetIndexFile;
+    private final List<Task> dependents = new LinkedList<>();
     private final List<Task> dependencies = new LinkedList<>();
 
     /**
@@ -51,12 +56,16 @@ public final class GameAssetDownloadTask extends Task {
     public GameAssetDownloadTask(AbstractDependencyManager dependencyManager, Version version) {
         this.dependencyManager = dependencyManager;
         this.version = version;
-        this.refreshTask = new GameAssetRefreshTask(dependencyManager, version);
+        this.assetIndexInfo = version.getAssetIndex();
+        this.assetIndexFile = dependencyManager.getGameRepository().getIndexFile(version.getId(), assetIndexInfo.getId());
+
+        if (!assetIndexFile.exists())
+            dependents.add(new GameAssetIndexDownloadTask(dependencyManager, version));
     }
 
     @Override
     public Collection<Task> getDependents() {
-        return Collections.singleton(refreshTask);
+        return dependents;
     }
 
     @Override
@@ -66,23 +75,28 @@ public final class GameAssetDownloadTask extends Task {
     
     @Override
     public void execute() throws Exception {
-        for (Map.Entry<File, AssetObject> entry : refreshTask.getResult()) {
+        AssetIndex index = Constants.GSON.fromJson(FileUtils.readText(assetIndexFile), AssetIndex.class);
-            if (Thread.interrupted())
+        int progress = 0;
-                throw new InterruptedException();
+        if (index != null)
+            for (AssetObject assetObject : index.getObjects().values()) {
+                if (Thread.interrupted())
+                    throw new InterruptedException();
 
-            File file = entry.getKey();
+                File file = dependencyManager.getGameRepository().getAssetObject(version.getId(), assetIndexInfo.getId(), assetObject);
-            AssetObject assetObject = entry.getValue();
+                if (file.isFile())
-            String url = dependencyManager.getDownloadProvider().getAssetBaseURL() + assetObject.getLocation();
+                    LocalRepository.getInstance().tryCacheFile(file.toPath(), LocalRepository.SHA1, assetObject.getHash());
-            if (!FileUtils.makeDirectory(file.getAbsoluteFile().getParentFile())) {
+                else {
-                Logging.LOG.log(Level.SEVERE, "Unable to create new file " + file + ", because parent directory cannot be created");
+                    String url = dependencyManager.getDownloadProvider().getAssetBaseURL() + assetObject.getLocation();
-                continue;
+                    FileDownloadTask task = new FileDownloadTask(NetworkUtils.toURL(url), file, new FileDownloadTask.IntegrityCheck("SHA-1", assetObject.getHash()));
+                    task.setName(assetObject.getHash());
+                    dependencies.add(task
+                            .setCaching(true)
+                            .setCandidate(LocalRepository.getInstance().getCommonDirectory()
+                                    .resolve("assets").resolve("objects").resolve(assetObject.getLocation())));
+                }
+
+                updateProgress(++progress, index.getObjects().size());
             }
-            if (file.isDirectory() || file.isFile() && file.exists())
-                continue;
-            FileDownloadTask task = new FileDownloadTask(NetworkUtils.toURL(url), file, new IntegrityCheck("SHA-1", assetObject.getHash()));
-            task.setName(assetObject.getHash());
-            dependencies.add(task);
-        }
     }
     
 }

HMCLCore/src/main/java/org/jackhuang/hmcl/download/game/GameAssetIndexDownloadTask.java

@@ -22,11 +22,10 @@ import org.jackhuang.hmcl.game.AssetIndexInfo;
 import org.jackhuang.hmcl.game.Version;
 import org.jackhuang.hmcl.task.FileDownloadTask;
 import org.jackhuang.hmcl.task.Task;
-import org.jackhuang.hmcl.util.FileUtils;
+import org.jackhuang.hmcl.util.LocalRepository;
 import org.jackhuang.hmcl.util.NetworkUtils;
 
 import java.io.File;
-import java.io.IOException;
 import java.util.LinkedList;
 import java.util.List;
 
@@ -61,9 +60,6 @@ public final class GameAssetIndexDownloadTask extends Task {
     @Override
     public void execute() throws Exception {
         AssetIndexInfo assetIndexInfo = version.getAssetIndex();
-        File assetDir = dependencyManager.getGameRepository().getAssetDirectory(version.getId(), assetIndexInfo.getId());
-        if (!FileUtils.makeDirectory(assetDir))
-            throw new IOException("Cannot create directory: " + assetDir);
         File assetIndexFile = dependencyManager.getGameRepository().getIndexFile(version.getId(), assetIndexInfo.getId());
 
         // We should not check the hash code of asset index file since this file is not consistent
@@ -71,7 +67,9 @@ public final class GameAssetIndexDownloadTask extends Task {
         dependencies.add(new FileDownloadTask(
                 NetworkUtils.toURL(dependencyManager.getDownloadProvider().injectURL(assetIndexInfo.getUrl())),
                 assetIndexFile
-        ));
+        ).setCaching(true)
+                .setCandidate(LocalRepository.getInstance().getCommonDirectory()
+                        .resolve("assets").resolve("indexes").resolve(assetIndexInfo.getId() + ".json")));
     }
 
 }

HMCLCore/src/main/java/org/jackhuang/hmcl/download/game/GameAssetRefreshTask.java

@@ -1,94 +0,0 @@
-/*
- * Hello Minecraft! Launcher.
- * Copyright (C) 2018  huangyuhui <huanghongxun2008@126.com>
- * 
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation, either version 3 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program.  If not, see {http://www.gnu.org/licenses/}.
- */
-package org.jackhuang.hmcl.download.game;
-
-import org.jackhuang.hmcl.download.AbstractDependencyManager;
-import org.jackhuang.hmcl.game.AssetIndex;
-import org.jackhuang.hmcl.game.AssetIndexInfo;
-import org.jackhuang.hmcl.game.AssetObject;
-import org.jackhuang.hmcl.game.Version;
-import org.jackhuang.hmcl.task.Task;
-import org.jackhuang.hmcl.task.TaskResult;
-import org.jackhuang.hmcl.util.Constants;
-import org.jackhuang.hmcl.util.FileUtils;
-import org.jackhuang.hmcl.util.Pair;
-
-import java.io.File;
-import java.util.Collection;
-import java.util.LinkedList;
-import java.util.List;
-
-import static org.jackhuang.hmcl.util.Pair.pair;
-
-/**
- * This task is to extract all asset objects described in asset index json.
- *
- * @author huangyuhui
- */
-public final class GameAssetRefreshTask extends TaskResult<Collection<Pair<File, AssetObject>>> {
-
-    private final AbstractDependencyManager dependencyManager;
-    private final Version version;
-    private final AssetIndexInfo assetIndexInfo;
-    private final File assetIndexFile;
-    private final List<Task> dependents = new LinkedList<>();
-
-    /**
-     * Constructor.
-     *
-     * @param dependencyManager the dependency manager that can provides {@link org.jackhuang.hmcl.game.GameRepository}
-     * @param version the <b>resolved</b> version
-     */
-    public GameAssetRefreshTask(AbstractDependencyManager dependencyManager, Version version) {
-        this.dependencyManager = dependencyManager;
-        this.version = version;
-        this.assetIndexInfo = version.getAssetIndex();
-        this.assetIndexFile = dependencyManager.getGameRepository().getIndexFile(version.getId(), assetIndexInfo.getId());
-
-        if (!assetIndexFile.exists())
-            dependents.add(new GameAssetIndexDownloadTask(dependencyManager, version));
-    }
-
-    @Override
-    public List<Task> getDependents() {
-        return dependents;
-    }
-
-    @Override
-    public String getId() {
-        return ID;
-    }
-
-    @Override
-    public void execute() throws Exception {
-        AssetIndex index = Constants.GSON.fromJson(FileUtils.readText(assetIndexFile), AssetIndex.class);
-        List<Pair<File, AssetObject>> res = new LinkedList<>();
-        int progress = 0;
-        if (index != null)
-            for (AssetObject assetObject : index.getObjects().values()) {
-                if (Thread.interrupted())
-                    throw new InterruptedException();
-
-            res.add(pair(dependencyManager.getGameRepository().getAssetObject(version.getId(), assetIndexInfo.getId(), assetObject), assetObject));
-                updateProgress(++progress, index.getObjects().size());
-            }
-        setResult(res);
-    }
-
-    public static final String ID = "game_asset_refresh_task";
-}

HMCLCore/src/main/java/org/jackhuang/hmcl/download/game/GameDownloadTask.java

@@ -22,6 +22,7 @@ import org.jackhuang.hmcl.game.Version;
 import org.jackhuang.hmcl.task.FileDownloadTask;
 import org.jackhuang.hmcl.task.FileDownloadTask.IntegrityCheck;
 import org.jackhuang.hmcl.task.Task;
+import org.jackhuang.hmcl.util.LocalRepository;
 import org.jackhuang.hmcl.util.NetworkUtils;
 
 import java.io.File;
@@ -34,11 +35,13 @@ import java.util.List;
  */
 public final class GameDownloadTask extends Task {
     private final DefaultDependencyManager dependencyManager;
+    private final String gameVersion;
     private final Version version;
     private final List<Task> dependencies = new LinkedList<>();
 
-    public GameDownloadTask(DefaultDependencyManager dependencyManager, Version version) {
+    public GameDownloadTask(DefaultDependencyManager dependencyManager, String gameVersion, Version version) {
         this.dependencyManager = dependencyManager;
+        this.gameVersion = gameVersion;
         this.version = version;
 
         setSignificance(TaskSignificance.MODERATE);
@@ -56,8 +59,9 @@ public final class GameDownloadTask extends Task {
         dependencies.add(new FileDownloadTask(
                 NetworkUtils.toURL(dependencyManager.getDownloadProvider().injectURL(version.getDownloadInfo().getUrl())),
                 jar,
-                new IntegrityCheck("SHA-1", version.getDownloadInfo().getSha1())
+                IntegrityCheck.of(LocalRepository.SHA1, version.getDownloadInfo().getSha1()))
-        ));
+                .setCaching(true)
+                .setCandidate(LocalRepository.getInstance().getCommonDirectory().resolve("jars").resolve(gameVersion + ".jar")));
     }
     
 }

HMCLCore/src/main/java/org/jackhuang/hmcl/task/FileDownloadTask.java

@@ -28,7 +28,9 @@ import java.io.RandomAccessFile;
 import java.math.BigInteger;
 import java.net.HttpURLConnection;
 import java.net.URL;
+import java.nio.file.Path;
 import java.security.MessageDigest;
+import java.util.Optional;
 import java.util.logging.Level;
 
 import static java.util.Objects.requireNonNull;
@@ -50,6 +52,11 @@ public class FileDownloadTask extends Task {
             this.checksum = requireNonNull(checksum);
         }
 
+        public static IntegrityCheck of(String algorithm, String checksum) {
+            if (checksum == null) return null;
+            else return new IntegrityCheck(algorithm, checksum);
+        }
+
         public String getAlgorithm() {
             return algorithm;
         }
@@ -75,6 +82,8 @@ public class FileDownloadTask extends Task {
     private final IntegrityCheck integrityCheck;
     private final int retry;
     private final EventManager<FailedEvent<URL>> onFailed = new EventManager<>();
+    private Path candidate;
+    private boolean caching;
     private RandomAccessFile rFile;
     private InputStream stream;
 
@@ -146,9 +155,35 @@ public class FileDownloadTask extends Task {
         return file;
     }
 
+    public FileDownloadTask setCandidate(Path candidate) {
+        this.candidate = candidate;
+        return this;
+    }
+
+    public FileDownloadTask setCaching(boolean caching) {
+        this.caching = caching;
+        return this;
+    }
+
     @Override
     public void execute() throws Exception {
         URL currentURL = url;
+
+        // Check cache
+        if (integrityCheck != null && caching) {
+            Optional<Path> cache = LocalRepository.getInstance()
+                    .checkExistentFile(candidate, integrityCheck.getAlgorithm(), integrityCheck.getChecksum());
+            if (cache.isPresent()) {
+                try {
+                    FileUtils.copyFile(cache.get().toFile(), file);
+                    Logging.LOG.log(Level.FINER, "Successfully verified file " + file + " from " + currentURL);
+                    return;
+                } catch (IOException e) {
+                    Logging.LOG.log(Level.WARNING, "Failed to copy cache files", e);
+                }
+            }
+        }
+
         Logging.LOG.log(Level.FINER, "Downloading " + currentURL + " to " + file);
         Exception exception = null;
 
@@ -257,6 +292,17 @@ public class FileDownloadTask extends Task {
 
         if (exception != null)
             throw new IOException("Unable to download file " + currentURL + ". " + exception.getMessage(), exception);
+
+        if (caching) {
+            try {
+                if (integrityCheck == null)
+                    LocalRepository.getInstance().cacheFile(file.toPath(), LocalRepository.SHA1, Hex.encodeHex(DigestUtils.digest(LocalRepository.SHA1, file.toPath())));
+                else
+                    LocalRepository.getInstance().cacheFile(file.toPath(), integrityCheck.getAlgorithm(), integrityCheck.getChecksum());
+            } catch (IOException e) {
+                Logging.LOG.log(Level.WARNING, "Failed to cache file", e);
+            }
+        }
     }
 
 }

HMCLCore/src/main/java/org/jackhuang/hmcl/util/LocalRepository.java

@@ -0,0 +1,111 @@
+/*
+ * Hello Minecraft! Launcher.
+ * Copyright (C) 2017  huangyuhui <huanghongxun2008@126.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see {http://www.gnu.org/licenses/}.
+ */
+package org.jackhuang.hmcl.util;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.Optional;
+
+public class LocalRepository {
+    private Path commonDirectory;
+    private Path cacheDirectory;
+
+    protected void changeDirectory(Path commonDir) {
+        commonDirectory = commonDir;
+        cacheDirectory = commonDir.resolve("cache");
+    }
+
+    public Path getCommonDirectory() {
+        return commonDirectory;
+    }
+
+    public Path getCacheDirectory() {
+        return cacheDirectory;
+    }
+
+    protected Path getFile(String algorithm, String hash) {
+        return getCacheDirectory().resolve(algorithm).resolve(hash.substring(0, 2)).resolve(hash);
+    }
+
+    protected boolean fileExists(String algorithm, String hash) {
+        if (hash == null) return false;
+        Path file = getFile(algorithm, hash);
+        if (Files.exists(file)) {
+            try {
+                return Hex.encodeHex(DigestUtils.digest(algorithm, file)).equalsIgnoreCase(hash);
+            } catch (IOException e) {
+                return false;
+            }
+        } else {
+            return false;
+        }
+    }
+
+    public void tryCacheFile(Path path, String algorithm, String hash) throws IOException {
+        Path cache = getFile(algorithm, hash);
+        if (Files.exists(cache)) return;
+        FileUtils.copyFile(path.toFile(), cache.toFile());
+    }
+
+    public Path cacheFile(Path path, String algorithm, String hash) throws IOException {
+        Path cache = getFile(algorithm, hash);
+        FileUtils.copyFile(path.toFile(), cache.toFile());
+        return cache;
+    }
+
+    public Optional<Path> checkExistentFile(Path original, String algorithm, String hash) {
+        if (fileExists(algorithm, hash))
+            return Optional.of(getFile(algorithm, hash));
+
+        if (original != null && Files.exists(original)) {
+            if (hash != null) {
+                try {
+                    String checksum = Hex.encodeHex(DigestUtils.digest(algorithm, original));
+                    if (checksum.equalsIgnoreCase(hash))
+                        return Optional.of(restore(original, () -> cacheFile(original, algorithm, hash)));
+                } catch (IOException e) {
+                    // we cannot check the hashcode.
+                }
+            } else {
+                return Optional.of(original);
+            }
+        }
+
+        return Optional.empty();
+    }
+
+    protected Path restore(Path original, ExceptionalSupplier<Path, ? extends IOException> cacheSupplier) throws IOException {
+        Path cache = cacheSupplier.get();
+        Files.delete(original);
+        Files.createLink(original, cache);
+        return cache;
+    }
+
+    private static LocalRepository instance = new LocalRepository();
+
+    public static LocalRepository getInstance() {
+        return instance;
+    }
+
+    public static void setInstance(LocalRepository instance) {
+        LocalRepository.instance = instance;
+    }
+
+    public static final String SHA1 = "SHA-1";
+}