#333 Fix issue with reading 7Zip split files with headers not just in…

… first split part

src/main/java/net/lingala/zip4j/io/inputstream/NumberedSplitFileInputStream.java

@@ -0,0 +1,47 @@
+package net.lingala.zip4j.io.inputstream;
+
+import net.lingala.zip4j.model.FileHeader;
+import net.lingala.zip4j.model.enums.RandomAccessFileMode;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.RandomAccessFile;
+
+/**
+ * A split input stream for zip file split with 7-zip. They end with .zip.001, .zip.002, etc
+ */
+public class NumberedSplitFileInputStream extends SplitFileInputStream {
+
+  private RandomAccessFile randomAccessFile;
+
+  public NumberedSplitFileInputStream(File zipFile) throws IOException {
+    this.randomAccessFile = new NumberedSplitRandomAccessFile(zipFile, RandomAccessFileMode.READ.getValue());
+  }
+
+  @Override
+  public int read() throws IOException {
+    return randomAccessFile.read();
+  }
+
+  @Override
+  public int read(byte[] b) throws IOException {
+    return this.read(b,0, b.length);
+  }
+
+  @Override
+  public int read(byte[] b, int off, int len) throws IOException {
+    return randomAccessFile.read(b, off, len);
+  }
+
+  @Override
+  public void prepareExtractionForFileHeader(FileHeader fileHeader) throws IOException {
+    randomAccessFile.seek(fileHeader.getOffsetLocalHeader());
+  }
+
+  @Override
+  public void close() throws IOException {
+    if (randomAccessFile != null) {
+      randomAccessFile.close();
+    }
+  }
+}

src/main/java/net/lingala/zip4j/io/inputstream/SplitFileInputStream.java

@@ -0,0 +1,13 @@
+package net.lingala.zip4j.io.inputstream;
+
+import net.lingala.zip4j.model.FileHeader;
+
+import java.io.IOException;
+import java.io.InputStream;
+
+// Even though this abstract class has only abstract method definitions, it is not implemented as an interface because
+// implementations of this class has to be used as an inputstream to ZipInputStream
+public abstract class SplitFileInputStream extends InputStream {
+
+  public abstract void prepareExtractionForFileHeader(FileHeader fileHeader) throws IOException;
+}

src/main/java/net/lingala/zip4j/io/inputstream/SplitInputStream.java → src/main/java/net/lingala/zip4j/io/inputstream/ZipStandardSplitFileInputStream.java

@@ -6,27 +6,25 @@
 import java.io.File;
 import java.io.FileNotFoundException;
 import java.io.IOException;
-import java.io.InputStream;
 import java.io.RandomAccessFile;
 
-public abstract class SplitInputStream extends InputStream {
+/**
+ * A split input stream for zip file split as per zip specification. They end with .z01, .z02... .zip
+ */
+public class ZipStandardSplitFileInputStream extends SplitFileInputStream {
 
   protected RandomAccessFile randomAccessFile;
   protected File zipFile;
-
+  private int lastSplitZipFileNumber;
   private boolean isSplitZipArchive;
   private int currentSplitFileCounter = 0;
   private byte[] singleByteArray = new byte[1];
 
-  public SplitInputStream(File zipFile, boolean isSplitZipArchive, int lastSplitZipFileNumber) throws FileNotFoundException {
+  public ZipStandardSplitFileInputStream(File zipFile, boolean isSplitZipArchive, int lastSplitZipFileNumber) throws FileNotFoundException {
     this.randomAccessFile = new RandomAccessFile(zipFile, RandomAccessFileMode.READ.getValue());
     this.zipFile = zipFile;
     this.isSplitZipArchive = isSplitZipArchive;
-
-
-    if (isSplitZipArchive) {
-      currentSplitFileCounter = lastSplitZipFileNumber;
-    }
+    this.lastSplitZipFileNumber = lastSplitZipFileNumber;
   }
 
   @Override
@@ -60,6 +58,7 @@ public int read(byte[] b, int off, int len) throws IOException {
     return readLen;
   }
 
+  @Override
   public void prepareExtractionForFileHeader(FileHeader fileHeader) throws IOException {
 
     if (isSplitZipArchive && (currentSplitFileCounter != fileHeader.getDiskNumberStart())) {
@@ -70,6 +69,13 @@ public void prepareExtractionForFileHeader(FileHeader fileHeader) throws IOExcep
     randomAccessFile.seek(fileHeader.getOffsetLocalHeader());
   }
 
+  @Override
+  public void close() throws IOException {
+    if (randomAccessFile != null) {
+      randomAccessFile.close();
+    }
+  }
+
   protected void openRandomAccessFileForIndex(int zipFileIndex) throws IOException {
     File nextSplitFile = getNextSplitFile(zipFileIndex);
     if (!nextSplitFile.exists()) {
@@ -79,12 +85,18 @@ protected void openRandomAccessFileForIndex(int zipFileIndex) throws IOException
     randomAccessFile = new RandomAccessFile(nextSplitFile, RandomAccessFileMode.READ.getValue());
   }
 
-  protected abstract File getNextSplitFile(int zipFileIndex) throws IOException;
+  protected File getNextSplitFile(int zipFileIndex) throws IOException {
+    if (zipFileIndex == lastSplitZipFileNumber) {
+      return zipFile;
+    }
 
-  @Override
-  public void close() throws IOException {
-    if (randomAccessFile != null) {
-      randomAccessFile.close();
+    String currZipFileNameWithPath = zipFile.getCanonicalPath();
+    String extensionSubString = ".z0";
+    if (zipFileIndex >= 9) {
+      extensionSubString = ".z";
     }
+
+    return new File(currZipFileNameWithPath.substring(0,
+        currZipFileNameWithPath.lastIndexOf(".")) + extensionSubString + (zipFileIndex + 1));
   }
 }

src/main/java/net/lingala/zip4j/tasks/ExtractAllFilesTask.java

@@ -1,6 +1,6 @@
 package net.lingala.zip4j.tasks;
 
-import net.lingala.zip4j.io.inputstream.SplitInputStream;
+import net.lingala.zip4j.io.inputstream.SplitFileInputStream;
 import net.lingala.zip4j.io.inputstream.ZipInputStream;
 import net.lingala.zip4j.model.FileHeader;
 import net.lingala.zip4j.model.UnzipParameters;
@@ -17,7 +17,7 @@
 public class ExtractAllFilesTask extends AbstractExtractFileTask<ExtractAllFilesTaskParameters> {
 
   private final char[] password;
-  private SplitInputStream splitInputStream;
+  private SplitFileInputStream splitInputStream;
 
   public ExtractAllFilesTask(ZipModel zipModel, char[] password, UnzipParameters unzipParameters,
                              AsyncTaskParameters asyncTaskParameters) {

src/main/java/net/lingala/zip4j/tasks/ExtractFileTask.java

@@ -2,7 +2,7 @@
 
 import net.lingala.zip4j.exception.ZipException;
 import net.lingala.zip4j.headers.HeaderUtil;
-import net.lingala.zip4j.io.inputstream.SplitInputStream;
+import net.lingala.zip4j.io.inputstream.SplitFileInputStream;
 import net.lingala.zip4j.io.inputstream.ZipInputStream;
 import net.lingala.zip4j.model.FileHeader;
 import net.lingala.zip4j.model.UnzipParameters;
@@ -26,7 +26,7 @@
 public class ExtractFileTask extends AbstractExtractFileTask<ExtractFileTaskParameters> {
 
   private char[] password;
-  private SplitInputStream splitInputStream;
+  private SplitFileInputStream splitInputStream;
 
   public ExtractFileTask(ZipModel zipModel, char[] password, UnzipParameters unzipParameters,
                          AsyncTaskParameters asyncTaskParameters) {

src/main/java/net/lingala/zip4j/util/UnzipUtil.java

@@ -1,10 +1,10 @@
 package net.lingala.zip4j.util;
 
 import net.lingala.zip4j.exception.ZipException;
-import net.lingala.zip4j.io.inputstream.NumberedSplitInputStream;
-import net.lingala.zip4j.io.inputstream.SplitInputStream;
+import net.lingala.zip4j.io.inputstream.NumberedSplitFileInputStream;
+import net.lingala.zip4j.io.inputstream.SplitFileInputStream;
 import net.lingala.zip4j.io.inputstream.ZipInputStream;
-import net.lingala.zip4j.io.inputstream.ZipStandardSplitInputStream;
+import net.lingala.zip4j.io.inputstream.ZipStandardSplitFileInputStream;
 import net.lingala.zip4j.model.FileHeader;
 import net.lingala.zip4j.model.ZipModel;
 
@@ -21,7 +21,7 @@ public class UnzipUtil {
   public static ZipInputStream createZipInputStream(ZipModel zipModel, FileHeader fileHeader, char[] password)
       throws IOException {
 
-    SplitInputStream splitInputStream = null;
+    SplitFileInputStream splitInputStream = null;
     try {
       splitInputStream = createSplitInputStream(zipModel);
       splitInputStream.prepareExtractionForFileHeader(fileHeader);
@@ -51,15 +51,14 @@ public static void applyFileAttributes(FileHeader fileHeader, File file) {
     }
   }
 
-  public static SplitInputStream createSplitInputStream(ZipModel zipModel) throws IOException {
+  public static SplitFileInputStream createSplitInputStream(ZipModel zipModel) throws IOException {
     File zipFile = zipModel.getZipFile();
 
     if (zipFile.getName().endsWith(InternalZipConstants.SEVEN_ZIP_SPLIT_FILE_EXTENSION_PATTERN)) {
-      return new NumberedSplitInputStream(zipModel.getZipFile(), true,
-          zipModel.getEndOfCentralDirectoryRecord().getNumberOfThisDisk());
+      return new NumberedSplitFileInputStream(zipModel.getZipFile());
     }
 
-    return new ZipStandardSplitInputStream(zipModel.getZipFile(), zipModel.isSplitArchive(),
+    return new ZipStandardSplitFileInputStream(zipModel.getZipFile(), zipModel.isSplitArchive(),
         zipModel.getEndOfCentralDirectoryRecord().getNumberOfThisDisk());
   }
 

src/test/java/net/lingala/zip4j/ExtractZipFileIT.java

@@ -516,15 +516,15 @@ public void testExtractZipFileCRCError() throws IOException {
   @Test
   public void testExtractZipFileOf7ZipFormatSplitWithoutEncryption() throws IOException {
     List<File> filesToAddToZip = new ArrayList<>(FILES_TO_ADD);
-    filesToAddToZip.add(getTestFileFromResources("file_PDF_1MB.pdf"));
+    filesToAddToZip.add(0, getTestFileFromResources("file_PDF_1MB.pdf"));
     File firstSplitFile = createZipFileAndSplit(filesToAddToZip, 102400, false, null);
     verifyZipFileByExtractingAllFiles(firstSplitFile, outputFolder, 4);
   }
 
   @Test
   public void testExtractZipFileOf7ZipFormatSplitWithAESEncryption() throws IOException {
     List<File> filesToAddToZip = new ArrayList<>(FILES_TO_ADD);
-    filesToAddToZip.add(getTestFileFromResources("file_PDF_1MB.pdf"));
+    filesToAddToZip.add(0, getTestFileFromResources("file_PDF_1MB.pdf"));
     File firstSplitFile = createZipFileAndSplit(filesToAddToZip, 102000, true, EncryptionMethod.AES);
     verifyZipFileByExtractingAllFiles(firstSplitFile, PASSWORD, outputFolder, 4);
   }

src/test/java/net/lingala/zip4j/util/UnzipUtilIT.java

@@ -3,9 +3,9 @@
 import net.lingala.zip4j.AbstractIT;
 import net.lingala.zip4j.ZipFile;
 import net.lingala.zip4j.exception.ZipException;
-import net.lingala.zip4j.io.inputstream.NumberedSplitInputStream;
-import net.lingala.zip4j.io.inputstream.SplitInputStream;
-import net.lingala.zip4j.io.inputstream.ZipStandardSplitInputStream;
+import net.lingala.zip4j.io.inputstream.NumberedSplitFileInputStream;
+import net.lingala.zip4j.io.inputstream.SplitFileInputStream;
+import net.lingala.zip4j.io.inputstream.ZipStandardSplitFileInputStream;
 import net.lingala.zip4j.model.FileHeader;
 import net.lingala.zip4j.model.ZipModel;
 import net.lingala.zip4j.testutils.TestUtils;
@@ -109,19 +109,19 @@ public void testCreateSplitInputStreamForNumberedSplitZipReturnsInstance() throw
     ZipModel zipModel = createZipModel();
     zipModel.setZipFile(zipFile);
 
-    SplitInputStream splitInputStream = UnzipUtil.createSplitInputStream(zipModel);
+    SplitFileInputStream splitInputStream = UnzipUtil.createSplitInputStream(zipModel);
 
-    assertThat(splitInputStream).isInstanceOf(NumberedSplitInputStream.class);
+    assertThat(splitInputStream).isInstanceOf(NumberedSplitFileInputStream.class);
   }
 
   @Test
   public void testCreateSplitInputStreamForNonNumberedSplitZipReturnsInstance() throws IOException {
     temporaryFolder.newFile(generatedZipFile.getName());
     ZipModel zipModel = createZipModel();
 
-    SplitInputStream splitInputStream = UnzipUtil.createSplitInputStream(zipModel);
+    SplitFileInputStream splitInputStream = UnzipUtil.createSplitInputStream(zipModel);
 
-    assertThat(splitInputStream).isInstanceOf(ZipStandardSplitInputStream.class);
+    assertThat(splitInputStream).isInstanceOf(ZipStandardSplitFileInputStream.class);
   }
 
   private ZipFile createZipFile() throws ZipException {