Glassfish - 上传图片 - 做得对 [英] Glassfish - uploading images - doing it right

问题描述

我正在使用最新的glassfish（3.1.2） - 因此不需要apache FileItem，也不需要使用getPart（）。我读过上传图片的最佳做法是将它们保存在文件系统中（参见这里例如）。我正在编辑已经存在的代码 - 很臭 - 所以我有想法：

I am on latest glassfish (3.1.2) - so no need for apache FileItem and no bugs with getPart(). I read that the best practice on uploading images is saving them on the file system (see here for instance). I am editing already existing code - smelly at that - so I had the idea to do :

Part p1 = request.getPart("file");
System.out.println("!!!!!P1 : " + p1);

打印：

!!!!!P1 : File name=DSC03660.JPG, 
StoreLocation=C:\_\glassfish3\glassfish\domains\domain1\generated\jsp\elkethe\upload_7cb06306_138b413999a__7ffa_00000000.tmp, 
size=2589152bytes, isFormField=false, FieldName=file

我的新线。在人们正在做的代码中：

newlines mine. In the code people are doing :

if (request.getParameter("crop") != null) {
    // get path on the server
    String outputpath = this.getServletContext().getRealPath(
            "images/temp/" + session.getId() + ".jpg");
    // store photo
    InputStream is = p1.getInputStream();
    createPhoto(is, outputpath);
    session.setAttribute("photo_path", "images/temp/" + session.getId()
            + ".jpg");
    response.sendRedirect("cropping");
    return;
}

其中

private void createPhoto(InputStream is, String outputpath) {
    FileOutputStream os = null;
    try {
        os = new FileOutputStream(outputpath);
        // write bytes taken from uploaded file to target file
        int ch = is.read();
        while (ch != -1) {
            os.write(ch);
            ch = is.read();
        }
    } catch (Exception ex) {
        ex.printStackTrace();
    } finally {
        Helpers.close(os);
    }
}

现在发生的事情是文件上传到StoreLocation（???）在提交表单时显然所有这些 p1.getInputStream（）都是徒劳的。

Now what happens is that the file is uploaded in the StoreLocation (???) on submitting the form so apparently all this p1.getInputStream() is for naught.

我的问题是：

• 什么是StoreLocation？那些glassfish上传的tmp怎么样？这些参数设置在哪里？我确实读过BalusC的'教程 - 但没有提到StoreLocation（谷歌不是很有帮助 ） 。


• 处理这种情况的更专业的方法是什么 - 包括将照片保存在webroot之外 - 但是使用glassfish提供的设施（如果确实提供）？


• 即使是p1打印这么好也逃过了我（它不是似乎覆盖 toString（））

• what is StoreLocation ? How tmp are those glassfish uploads ? Where are all those parameters set ? I did read BalusC' tutorial - but there is no mention of StoreLocation (google is not very helpful either).
• What would be a more professional way of handling the situation - including keeping the photos outside the webroot - but using facilities glassfish provides (if it does provide) ?
• Even p1 printing so nice escapes me (it does not seem to Override toString())

对于如何重命名照片等感兴趣的提示（这个会话ID是对的吗？ - 还检查时间技巧）：

Interested in tips even in how should one rename the photos etc (is this sessionID thing Right ? - check also the time trick) :

if (request.getParameter("save") != null) {
    long time = System.currentTimeMillis();
    String path = "images/upload/" + session.getId() + time + ".jpg";
    String outputpath = this.getServletContext().getRealPath(path);
    // store photo
    InputStream is = p1.getInputStream();
    createPhoto(is, outputpath);
    // etc
}

推荐答案

什么是StoreLocation？那些glassfish上传的tmp怎么样？所有这些参数设置在哪里？

What is StoreLocation ? How tmp are those glassfish uploads ? Where are all those parameters set ?

StoreLocation 就是java.io 。code> FileItem 的
数据在磁盘上的临时位置的.File对象。驻留在 javax.servlet.context.tempdir ，默认为％GLASSFISH_HOME％\ domain \ domain1 \ generated\jsp\webApp 。这些上传与tmp一样（文件的生命周期与 FileItem 实例的生命周期相关;当实例被垃圾收集时，文件将被删除 - 来自这里）。尚未设法以编程方式更改 javax.servlet.context.tempdir 的值（请注释） - 它是 tempdir sun-web-app元素的属性 sun-web.xml。

StoreLocation is just the the java.io.File object for the FileItem's data's temporary location on the disk. Resides in javax.servlet.context.tempdir which defaults to %GLASSFISH_HOME%\domains\domain1\generated\jsp\webApp. Those uploads are as tmp as anything (The lifetime of the file is tied to the lifetime of the FileItem instance; the file will be deleted when the instance is garbage collected - from here). Haven't yet managed to change the value of javax.servlet.context.tempdir programmatically (comment please) - it is the tempdir property of the sun-web-app element of the sun-web.xml.

处理这种情况的更专业的方法是什么 - 包括保留照片在webroot之外 - 但是使用glassfish提供的设施（如果确实提供）？

What would be a more professional way of handling the situation - including keeping the photos outside the webroot - but using facilities glassfish provides (if it does provide) ?

更专业的方法是使用 Part.write（）将移动文件移至所需位置。由于glassfish的实现，你无法提供绝对的写作路径 - 一件苦差事。我问了​​这里。

Well a more professional way is to Use Part.write() to move the file to the desired location. Due to glassfish implementation though you can't supply an absolute path to write - a chore. I asked here.

关于保存文件的位置： https://stackoverflow.com/a/18664715/281545

As to where to save the file : https://stackoverflow.com/a/18664715/281545

用于保存文件 - 从应用程序外部的位置提供服务，您需要在sun-web.xml（或glassfish-）中定义alternatedocroot属性web.xml）。

That is for saving the file - to serve it from a location outside the app you need to define "alternatedocroot" properties in the sun-web.xml (or glassfish-web.xml).

即使是p1打印这么好逃脱了我（它似乎没有覆盖toString（））

Even p1 printing so nice escapes me (it does not seem to Override toString())

哦是的确实

感兴趣的提示甚至应该如何重命名照片等（这个sessionID是对的吗？ - 检查时间tr ick）

Interested in tips even in how should one rename the photos etc (is this sessionID thing Right ? - check also the time trick)

不，不是 - 我倾向于文件#createTempFile（） - 无论如何这是一个不同的问题，请这里

No it is not - I tend towards File#createTempFile() - anyway this is a different question asked here

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