java - ZipOutputStream保留大小= -1

我正在使用非常标准的代码使用ZipOutputStream创建一个zip文件。由于某种原因，当我以ZipInputStream的形式读回它时，ZipEntry具有size=-1。文件名已正确存储在ZipEntry中。

（当我使用操作系统工具制作一个zip文件，然后将其读回时，大小是正确的，因此我认为问题出在ZipOutputStream而不是ZipInputStream）。

上下文是一个Spring MVC控制器。

我究竟做错了什么？
谢谢。

这是代码：

// export zip file
String file = "/Users/me/Desktop/test.jpg";
FileInputStream fis = new FileInputStream(file);
FileOutputStream fos = new FileOutputStream(file+".zip");
ZipOutputStream zos = new ZipOutputStream(fos);
zos.putNextEntry(new ZipEntry("test.jpg"));
byte[] buffer = new byte[1024];
int bytesRead;
while ((bytesRead = fis.read(buffer)) > 0) {
    zos.write(buffer, 0, bytesRead);
}
zos.closeEntry();
zos.close();
fis.close();

// import same file
String file2 = "/Users/me/Desktop/test.jpg.zip";
FileInputStream fis2 = new FileInputStream(file2);
ZipInputStream zis = new ZipInputStream(fis2);
ZipEntry entry = zis.getNextEntry();
// here: entry.getSize() = -1, zip.buf is an array of zeros...
// but if I unzip the file on my OS I see that the original file has been zipped...

最佳答案

您必须从流中获取下一个条目，例如以下示例：

http://www.roseindia.net/tutorial/java/corejava/zip/zipentry.html

当您手动设置尺寸时，它肯定会给您结果，就像您显示的是“ 64527”一样。
您最好看看zip示例。他们会给您清晰的图像。
另外：Create Java-Zip-Archive from existing OutputStream

尝试这样的事情：

        String inputFileName = "test.txt";
        String zipFileName = "compressed.zip";

        //Create input and output streams
        FileInputStream inStream = new FileInputStream(inputFileName);
        ZipOutputStream outStream = new ZipOutputStream(new FileOutputStream(zipFileName));

        // Add a zip entry to the output stream
        outStream.putNextEntry(new ZipEntry(inputFileName));

        byte[] buffer = new byte[1024];
        int bytesRead;

        //Each chunk of data read from the input stream
        //is written to the output stream
        while ((bytesRead = inStream.read(buffer)) > 0) {
            outStream.write(buffer, 0, bytesRead);
        }

        //Close zip entry and file streams
        outStream.closeEntry();

        outStream.close();
        inStream.close();