+/* ownCloud Android client application
+ * Copyright (C) 2015 ownCloud Inc.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2,
+ * as published by the Free Software Foundation.
+ *
+ * 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 com.owncloud.android.files.services;
+
+import android.accounts.Account;
+
+import com.owncloud.android.datamodel.OCFile;
+
+import java.io.File;
+import java.util.HashSet;
+import java.util.Set;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.concurrent.ConcurrentMap;
+
+/**
+ * Helper structure to keep the trees of folders containing any file downloading or synchronizing.
+ *
+ * A map provides the indexation based in hashing.
+ *
+ * A tree is created per account.
+ *
+ * @author David A. Velasco
+ */
+public class IndexedForest<V> {
+
+ private ConcurrentMap<String, Node<V>> mMap = new ConcurrentHashMap<String, Node<V>>();
+
+ private class Node<V> {
+ String mKey = null;
+ Node<V> mParent = null;
+ Set<Node<V>> mChildren = new HashSet<Node<V>>(); // TODO be careful with hash()
+ V mPayload = null;
+
+ // payload is optional
+ public Node(String key, V payload) {
+ if (key == null) {
+ throw new IllegalArgumentException("Argument key MUST NOT be null");
+ }
+ mKey = key;
+ mPayload = payload;
+ }
+
+ public Node<V> getParent() {
+ return mParent;
+ };
+
+ public Set<Node<V>> getChildren() {
+ return mChildren;
+ }
+
+ public String getKey() {
+ return mKey;
+ }
+
+ public V getPayload() {
+ return mPayload;
+ }
+
+ public void addChild(Node<V> child) {
+ mChildren.add(child);
+ child.setParent(this);
+ }
+
+ private void setParent(Node<V> parent) {
+ mParent = parent;
+ }
+
+ public boolean hasChildren() {
+ return mChildren.size() > 0;
+ }
+
+ public void removeChild(Node<V> removed) {
+ mChildren.remove(removed);
+ }
+ }
+
+
+ public /* synchronized */ String putIfAbsent(Account account, String remotePath, V value) {
+ String targetKey = buildKey(account, remotePath);
+ Node<V> valuedNode = new Node(targetKey, value);
+ mMap.putIfAbsent(
+ targetKey,
+ valuedNode
+ );
+
+ String currentPath = remotePath, parentPath = null, parentKey = null;
+ Node<V> currentNode = valuedNode, parentNode = null;
+ boolean linked = false;
+ while (!OCFile.ROOT_PATH.equals(currentPath) && !linked) {
+ parentPath = new File(currentPath).getParent();
+ if (!parentPath.endsWith(OCFile.PATH_SEPARATOR)) {
+ parentPath += OCFile.PATH_SEPARATOR;
+ }
+ parentKey = buildKey(account, parentPath);
+ parentNode = mMap.get(parentKey);
+ if (parentNode == null) {
+ parentNode = new Node(parentKey, null);
+ parentNode.addChild(currentNode);
+ mMap.put(parentKey, parentNode);
+ } else {
+ parentNode.addChild(currentNode);
+ linked = true;
+ }
+ currentPath = parentPath;
+ currentNode = parentNode;
+ }
+
+ return targetKey;
+ };
+
+ public /* synchronized */ V remove(Account account, String remotePath) {
+ String targetKey = buildKey(account, remotePath);
+ Node<V> firstRemoved = mMap.remove(targetKey);
+
+ if (firstRemoved != null) {
+ Node<V> removed = firstRemoved;
+ Node<V> parent = removed.getParent();
+ while (parent != null) {
+ parent.removeChild(removed);
+ if (!parent.hasChildren()) {
+ removed = mMap.remove(parent.getKey());
+ parent = removed.getParent();
+ } else {
+ parent = null;
+ }
+ }
+ }
+
+ if (firstRemoved != null) {
+ return firstRemoved.getPayload();
+ } else {
+ return null;
+ }
+
+ }
+
+ public boolean contains(Account account, String remotePath) {
+ String targetKey = buildKey(account, remotePath);
+ return mMap.containsKey(targetKey);
+ }
+
+ public /* synchronized */ V get(String key) {
+ Node<V> node = mMap.get(key);
+ if (node != null) {
+ return node.getPayload();
+ } else {
+ return null;
+ }
+ }
+
+
+ /**
+ * Builds a key to index files
+ *
+ * @param account Account where the file to download is stored
+ * @param remotePath Path of the file in the server
+ */
+ private String buildKey(Account account, String remotePath) {
+ return account.name + remotePath;
+ }
+
+
+
+}
projects / pub / Android / ownCloud.git / commitdiff