从java webstart应用程序中的jar获取资源 [英] Getting resources from jar in a java webstart application

问题描述

我正在尝试在Java webstart应用程序中加载大量资源。

I am trying to load a number of resources in a Java webstart application.

我最初尝试使用以下方法加载这些资源：

I had originally tried to load these using:

ClassLoader loader = MyClass.class.getClassLoader();
URL url = loader.getResource("resourceName");
File file = new File(url.toURI());

但是这不起作用 - 它抛出了IllegalArgumentException。进一步的研究表明，这种方法不适用于从jar文件访问资源，我需要使用以下方法：

But this didn't work - it threw an IllegalArgumentException. Further research suggested that this approach doesn't work with accessing resources from jar files, and that I need to use the following approach:

ClassLoader loader = MyClass.class.getClassLoader();
InputStream in = loader.getResourceAsStream("resourceName");

然而，当我使用Jnlp运行时，我得到奇怪的结果。如果我运行以下命令：

However, I get odd results when I run this using from the Jnlp. If I run the following:

public static void main(String[] args) throws IOException, URISyntaxException {
  ClassLoader loader = MyClass.class.getClassLoader();
  String r = "resourceName";
  URL url = loader.getResource(r);
  System.out.println(url!=null);
  InputStream in = loader.getResourceAsStream(r);
  System.out.println(in!=null);
}

在我的IDE中，我得到了真实的&是的（正如我所料）。
从jnlp运行，我得到的是URL，但是对于InputStream是假的。

In my IDE, I get true & true (as I would expect). Running from the jnlp, I get true for the URL, but false for the InputStream.

关于我可能做错的任何想法？
有没有更好的方法来加载资源以便在java webstart应用程序中使用？

Any ideas on what I might be doing wrong? Are there better ways of loading resources for use in the java webstart application?

编辑：有关信息，我的资源在MyProject / src / main / resources中，当生成jar时，资源都在jar根目录中。

For info, my resources are in MyProject/src/main/resources, and when the jar is generated, the resources are in the jar root.

推荐答案

好的 - 问题是我是尝试访问资源目录（例如，从我的问题中的示例，resourceName是资源文件的目录）。

Ok - so the problem was that I was trying to access directory of resources (i.e. from the example in my question, resourceName is a directory of resource files).

虽然可以通过这种方式访问​​资源大多数环境（例如在IDE中），从Java webstart运行时是不可能的。

Whilst it is possible to access resources in this way in most environments (e.g. in an IDE), it is not possible when running from Java webstart.

我发现这个页面特别有帮助：
http://lopica.sourceforge.net/faq.html#listresources

I found this page particularly helpful: http://lopica.sourceforge.net/faq.html#listresources

...并且遵循该方法制作资源目录，然后我可以迭代以获取相关资源。

...and have followed that approach to make a catalogue of resources, that I can then iterate through to get the relevant resources.

这篇关于从java webstart应用程序中的jar获取资源的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！