IllegalArgumentException in ZipInputStream while reading unicode file

Name: nt126004 Date: 11/27/2001


java version "1.4.0-beta3"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.0-beta3-b84)
Java HotSpot(TM) Client VM (build 1.4.0-beta3-b84, mixed mode)

java.until.zip.ZipFile or ZipInputStream can't unzip file(unicode name) in zip
by winzip8.0

source code:
import java.util.zip.*;
import java.io.*;
public class UnzipF {
    
   private String filename;
    
   public UnzipF(String filename){
      this.filename = filename;
   }
    
   public boolean unzip(){
      try {
         String topdir = filename.substring(0,filename.indexOf(".zip"));
         if (!(new java.io.File(topdir)).mkdir()) System.out.println("topdir of
filename can't created!");
          
         ZipInputStream in = new ZipInputStream(new FileReader(filename));
         //ZipInputStream in = new ZipInputStream(new DataInputStream(new
java.io.FileInputStream(filename)));
         ZipEntry entry;
         String entryname;
         byte[] buf = new byte[4096];
         int len,length;
         String outFilename;
         OutputStream out;
         String dirname;
         while ((entry = in.getNextEntry()) != null) {
            entryname = entry.getName();
            if (!entry.isDirectory()){
               int index = entryname.lastIndexOf('/');
               if(index != -1){
                  dirname = entryname.substring(0,index+1);
                  if (!(new java.io.File(topdir+'/'+dirname)).exists()) (new
java.io.File(topdir+'/'+dirname)).mkdirs() ;
               }
               outFilename = topdir + '/' + entryname;
               out = new java.io.FileOutputStream(outFilename);
               length = 0 ;
               while ((len = in.read(buf)) > 0) {
                  out.write(buf, 0, len);
                  length=length+len;
               }
               out.close();
               System.out.print("outFilename:"+outFilename);
               System.out.println(" length:"+length);
               //System.in.read();
            }
            else {
               if (!(new java.io.File(topdir+'/'+entryname)).exists()) (new
java.io.File(topdir+'/'+entryname)).mkdirs() ;
               System.out.println("topdir+'/'+entryname:"+topdir+'/'+entryname);
            }
         }
         in.close();
         return true;
      } catch (IOException e) {
       System.out.println("test");
       System.out.println(e.getMessage());
        return false;
      }
   }
   public static void main(String args[]) {
     UnzipF uf = new UnzipF(args[0]);
     uf.unzip();
   }
}

readme.zip's entry(zip by winzip8.0):
复件 readme.txt
readme.txt


commad:java UnzipF readme.zip

Exception:
Exception in thread "main" java.lang.IllegalArgumentException
        at java.util.zip.ZipInputStream.getUTF8String(ZipInputStream.java:291)
        at java.util.zip.ZipInputStream.readLOC(ZipInputStream.java:230)
        at java.util.zip.ZipInputStream.getNextEntry(ZipInputStream.java:75)
        at UnzipF.unzip(UnzipF.java:24)
        at UnzipF.main(UnzipF.java:58)
(Review ID: 135772)
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