Java example source code file (LargeZip.java)

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Java - Java tags/keywords

bufferedoutputstream, bytearrayoutputstream, data_size, file, fileoutputstream, filesystemprovider, inputstream, ioexception, largezip, nio, object, path, string, throwable, util, zip, zipentry

The LargeZip.java Java example source code

/*
 * Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

import java.io.*;
import java.nio.*;
import java.nio.file.*;
import java.nio.file.attribute.*;
import java.nio.file.spi.*;
import java.util.*;
import java.util.zip.*;

import static java.nio.file.StandardCopyOption.*;

public class LargeZip {
     // If true, don't delete large ZIP file created for test.
     static final boolean debug = System.getProperty("debug") != null;

     //static final int DATA_LEN = 1024 * 1024;
     static final int DATA_LEN = 80 * 1024;
     static final int DATA_SIZE = 8;

     static long fileSize = 6L * 1024L * 1024L * 1024L; // 6GB

     static boolean userFile = false;
     static byte[] data;
     static File largeFile;
     static String lastEntryName;

     /* args can be empty, in which case check a 3 GB file which is created for
      * this test (and then deleted).  Or it can be a number, in which case
      * that designates the size of the file that's created for this test (and
      * then deleted).  Or it can be the name of a file to use for the test, in
      * which case it is *not* deleted.  Note that in this last case, the data
      * comparison might fail.
      */
     static void realMain (String[] args) throws Throwable {
         if (args.length > 0) {
             try {
                 fileSize = Long.parseLong(args[0]);
                 System.out.println("Testing with file of size " + fileSize);
             } catch (NumberFormatException ex) {
                 largeFile = new File(args[0]);
                 if (!largeFile.exists()) {
                     throw new Exception("Specified file " + args[0] + " does not exist");
                 }
                 userFile = true;
                 System.out.println("Testing with user-provided file " + largeFile);
             }
         }
         File testDir = null;
         if (largeFile == null) {
             testDir = new File(System.getProperty("test.scratch", "."),
                                     "LargeZip");
             if (testDir.exists()) {
                 if (!testDir.delete()) {
                     throw new Exception("Cannot delete already-existing test directory");
                 }
             }
             check(!testDir.exists() && testDir.mkdirs());
             largeFile = new File(testDir, "largezip.zip");
             createLargeZip();
         } else {
             if (args.length > 1)
                 updateLargeZip(args[1]); // add new entry with zfs
         }
         readLargeZip1();
         readLargeZip2();

         if (!userFile && !debug) {
             check(largeFile.delete());
             check(testDir.delete());
         }
     }

     static void createLargeZip() throws Throwable {
         int iterations = DATA_LEN / DATA_SIZE;
         ByteBuffer bb = ByteBuffer.allocate(DATA_SIZE);
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
         for (int i = 0; i < iterations; i++) {
             bb.putDouble(0, Math.random());
             baos.write(bb.array(), 0, DATA_SIZE);
         }
         data = baos.toByteArray();

         try (FileOutputStream fos = new FileOutputStream(largeFile);
              BufferedOutputStream bos = new BufferedOutputStream(fos);
              ZipOutputStream zos = new ZipOutputStream(bos))
         {
             long length = 0;
             while (length < fileSize) {
                 ZipEntry ze = new ZipEntry("entry-" + length);
                 lastEntryName = ze.getName();
                 zos.putNextEntry(ze);
                 zos.write(data, 0, data.length);
                 zos.closeEntry();
                 length = largeFile.length();
             }
             System.out.println("Last entry written is " + lastEntryName);
         }
     }

     private static byte buf[] = new byte[4096];

     static void checkEntry(ZipEntry e, InputStream is) throws Throwable {
         long N = 0;
         int n = 0;
         while ((n = is.read(buf)) >= 0) {
            N += n;
         }
         check(N == e.getSize());
     }

     static void readLargeZip1() throws Throwable {
          ZipFile zipFile = new ZipFile(largeFile);
          ZipEntry entry = null;
          String entryName = null;
          int count = 0;
          System.out.println("ZipFile:");
          Enumeration<? extends ZipEntry> entries = zipFile.entries();
          while (entries.hasMoreElements()) {
               entry = entries.nextElement();
               entryName = entry.getName();
               System.out.println("    checking " + entryName);
               if (!entry.isDirectory()) {
                    try (InputStream zeis = zipFile.getInputStream(entry)) {
                        checkEntry(entry, zeis);
                    }
               }
               count++;
          }
          System.out.println("Number of entries read: " + count);
          check(!entry.isDirectory());
          if (userFile || check(entryName.equals(lastEntryName))) {
               ByteArrayOutputStream baos = new ByteArrayOutputStream();
               InputStream is = zipFile.getInputStream(entry);
               int len;
               while ((len = is.read(buf)) >= 0) {
                    baos.write(buf, 0, len);
               }
               baos.close();
               is.close();
               if (!userFile)
                   check(Arrays.equals(data, baos.toByteArray()));
          }
     }

     static void readLargeZip2() throws Throwable {
         System.out.println("ZipInputStream:");
         try (FileInputStream fis = new FileInputStream(largeFile);
              BufferedInputStream bis = new BufferedInputStream(fis);
              ZipInputStream zis = new ZipInputStream(bis))
         {
             ZipEntry entry = null;
             String entryName = null;
             int count = 0;
             while ((entry = zis.getNextEntry()) != null) {
                  entryName = entry.getName();

                  System.out.println("    checking " + entryName +
                                     ", method=" + entry.getMethod());
                  if (entryName.equals(lastEntryName)) {
                       break;
                  }
                  if (!entry.isDirectory()) {
                       checkEntry(entry, zis);
                  }
                  count++;
             }
             System.out.println("Number of entries read: " + count);
             System.out.println("Last entry read is " + entryName);
             if (!userFile) {
                  check(!entry.isDirectory());
                  ByteArrayOutputStream baos = new ByteArrayOutputStream();
                  byte buf[] = new byte[4096];
                  int len;
                  while ((len = zis.read(buf)) >= 0) {
                       baos.write(buf, 0, len);
                  }
                  baos.close();
                  check(Arrays.equals(data, baos.toByteArray()));
                  check(zis.getNextEntry() == null);
             }
         }
     }

     private static void updateFile(FileSystem fs, Path src) throws IOException {
          Path dst = fs.getPath(src.toString());
          Path parent = dst.getParent();
          if (parent != null && Files.notExists(parent))
               Files.createDirectories(parent);
          Files.copy(src, dst, REPLACE_EXISTING);
     }

     private static FileSystemProvider getZipFSProvider() {
         for (FileSystemProvider provider : FileSystemProvider.installedProviders()) {
              if ("jar".equalsIgnoreCase(provider.getScheme()))
                   return provider;
         }
         return null;
     }

     static void updateLargeZip(String pName) throws Throwable {
         FileSystemProvider provider = getZipFSProvider();
         if (provider == null) {
             System.err.println("ZIP filesystem provider is not installed");
             System.exit(1);
         }
         Map<String, Object> env = env = new HashMap<>();
         try (FileSystem fs = provider.newFileSystem(largeFile.toPath(), env)) {
             Path path = FileSystems.getDefault().getPath(pName);
             Files.walkFileTree(
                 path,
                 new SimpleFileVisitor<Path>() {
                     @Override
                     public FileVisitResult visitFile(Path file,
                                                      BasicFileAttributes attrs)
                         throws IOException
                     {
                         updateFile(fs, file);
                         return FileVisitResult.CONTINUE;
                     }
             });
         }
     }


     //--------------------- Infrastructure ---------------------------
     static volatile int passed = 0, failed = 0;
     static void pass() {passed++;}
     static void pass(String msg) {System.out.println(msg); passed++;}
     static void fail() {failed++; Thread.dumpStack();}
     static void fail(String msg) {System.out.println(msg); fail();}
     static void unexpected(Throwable t) {failed++; t.printStackTrace();}
     static void unexpected(Throwable t, String msg) {
         System.out.println(msg); failed++; t.printStackTrace();}
     static boolean check(boolean cond) {if (cond) pass(); else fail(); return cond;}
     static void equal(Object x, Object y) {
          if (x == null ? y == null : x.equals(y)) pass();
          else fail(x + " not equal to " + y);}
     public static void main(String[] args) throws Throwable {
          try {realMain(args);} catch (Throwable t) {unexpected(t);}
          System.out.println("\nPassed = " + passed + " failed = " + failed);
          if (failed > 0) throw new AssertionError("Some tests failed");}
}