Merge branch 'eximport' into dev

app/src/main/java/org/schabi/newpipe/util/ZipHelper.java

@@ -0,0 +1,94 @@
+package org.schabi.newpipe.util;
+
+import java.io.BufferedInputStream;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.util.zip.ZipEntry;
+import java.util.zip.ZipInputStream;
+import java.util.zip.ZipOutputStream;
+
+/**
+ * Created by Christian Schabesberger on 28.01.18.
+ * Copyright 2018 Christian Schabesberger <chris.schabesberger@mailbox.org>
+ * ZipHelper.java is part of NewPipe
+ *
+ * License: GPL-3.0+
+ * 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/>.
+ */
+
+public class ZipHelper {
+
+    private static final int BUFFER_SIZE = 2048;
+
+    /**
+     * This function helps to create zip files.
+     * Caution this will override the original file.
+     * @param outZip The ZipOutputStream where the data should be stored in
+     * @param file The path of the file that should be added to zip.
+     * @param name The path of the file inside the zip.
+     * @throws Exception
+     */
+    public static void addFileToZip(ZipOutputStream outZip, String file, String name) throws Exception {
+        byte data[] = new byte[BUFFER_SIZE];
+        FileInputStream fi = new FileInputStream(file);
+        BufferedInputStream inputStream = new BufferedInputStream(fi, BUFFER_SIZE);
+        ZipEntry entry = new ZipEntry(name);
+        outZip.putNextEntry(entry);
+        int count;
+        while((count = inputStream.read(data, 0, BUFFER_SIZE)) != -1) {
+            outZip.write(data, 0, count);
+        }
+        inputStream.close();
+    }
+
+    /**
+     * This will extract data from Zipfiles.
+     * Caution this will override the original file.
+     * @param inZip The ZipOutputStream where the data is stored in
+     * @param file The path of the file on the disk where the data should be extracted to.
+     * @param name The path of the file inside the zip.
+     * @return will return true if the file was found within the zip file
+     * @throws Exception
+     */
+    public static boolean extractFileFromZip(ZipInputStream inZip, String file, String name) throws Exception {
+        byte data[] = new byte[BUFFER_SIZE];
+
+        boolean found = false;
+
+        ZipEntry ze;
+        while((ze = inZip.getNextEntry()) != null) {
+            if(ze.getName().equals(name)) {
+                found = true;
+                // delete old file first
+                File oldFile = new File(file);
+                if(oldFile.exists()) {
+                    if(!oldFile.delete()) {
+                        throw new Exception("Could not delete " + file);
+                    }
+                }
+
+                FileOutputStream outFile = new FileOutputStream(file);
+                int count = 0;
+                while((count = inZip.read(data)) != -1) {
+                    outFile.write(data, 0, count);
+                }
+
+                outFile.close();
+                inZip.closeEntry();
+            }
+        }
+        return true;
+    }
+}