exception - java：创建新 zip 时出现 Zip 异常

Question

创建新的 zip 文件时，此异常意味着什么？

java.util.zip.ZipException：太短而不能 Zip

Answer 1

java.util.zipException: too short to be zip 意味着您的 Zip 无效。请检查您正在创建有效的 zip。

您可以找到示例

我已经验证并且下面的代码正在运行。

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipException;
import java.util.zip.ZipOutputStream;


public class CreateZipFileDirectory {

    public static void main(String args[])
    {                
            try
            {
                    String zipFile = "Path where zip needs to be creaetd e.g.zipdemo.zip";
                    String sourceDirectory = "directory which contains files.";

                    //create byte buffer
                    byte[] buffer = new byte[1024];
                    /*
                     * To create a zip file, use
                     *
                     * ZipOutputStream(OutputStream out)
                     * constructor of ZipOutputStream class.
                     *  
                     */

                     //create object of FileOutputStream
                     FileOutputStream fout = new FileOutputStream(zipFile);

                     //create object of ZipOutputStream from FileOutputStream
                     ZipOutputStream zout = new ZipOutputStream(fout);

                     //create File object from directory name
                     File dir = new File(sourceDirectory);

                     //check to see if this directory exists
                     if(!dir.isDirectory())
                     {
                            System.out.println(sourceDirectory + " is not a directory");
                     }
                     else
                     {
                            File[] files = dir.listFiles();

                            for(int i=0; i < files.length ; i++)
                            {
                                    System.out.println("Adding " + files[i].getName());

                                    //create object of FileInputStream for source file
                                    FileInputStream fin = new FileInputStream(files[i]);

                                    /*
                                     * To begin writing ZipEntry in the zip file, use
                                     *
                                     * void putNextEntry(ZipEntry entry)
                                     * method of ZipOutputStream class.
                                     *
                                     * This method begins writing a new Zip entry to
                                     * the zip file and positions the stream to the start
                                     * of the entry data.
                                     */

                                    zout.putNextEntry(new ZipEntry(files[i].getName()));

                                    /*
                                     * After creating entry in the zip file, actually
                                     * write the file.
                                     */
                                    int length;

                                    while((length = fin.read(buffer)) > 0)
                                    {
                                       zout.write(buffer, 0, length);
                                    }

                                    /*
                                     * After writing the file to ZipOutputStream, use
                                     *
                                     * void closeEntry() method of ZipOutputStream class to
                                     * close the current entry and position the stream to
                                     * write the next entry.
                                     */

                                     zout.closeEntry();
                                     //close the InputStream
                                     fin.close();
                            }
                     }

                      //close the ZipOutputStream
                      zout.close();

                      System.out.println("Zip file has been created!");

            }
            catch(IOException ioe)
            {
                    System.out.println("IOException :" + ioe);
            }

    }

}

/*
Output of this program would be
Adding nonav.log
Adding ospreg.exe
Adding servers.ini
Adding setupisam.log
Adding sourceFile1.doc
Adding sourceFile2.doc
Zip file has been created!
*/

Answer 2

看一下readCentralDir()方法，您将不得不更深入地查看代码，但一般来说，一旦文件太短而不能成为 ZIP 文件，似乎就会引发此异常。

以下代码行（mRaf 是随机访问文件）：

long scanOffset = mRaf.length() - ENDHDR;
if (scanOffset < 0) {
  throw new ZipException("too short to be Zip");
}