在 java webstart 应用程序中从 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:

I had originally tried to load these using:

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

但这没有用——它抛出了一个 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");

但是，当我使用 Jnlp 运行它时，我得到了奇怪的结果.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，我得到真正的 &真的(正如我所料).从 jnlp 运行，URL 为 true，但 InputStream 为 false.

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.

关于我可能做错了什么的任何想法?有没有更好的方法来加载资源以在 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?

有关信息，我的资源在 MyProject/src/main/resources 中，生成 jar 时，资源在 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 - 所以问题是我试图访问资源目录(即从我问题中的示例中，resourceName 是一个资源文件目录).

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).

虽然在大多数环境中(例如在 IDE 中)可以通过这种方式访问​​资源，但从 Java webstart 运行时则无法访问.

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用:http://lopica.sourceforge.net/faq.html#listresources

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

...并按照这种方法制作了一个资源目录，然后我可以遍历该目录以获取相关资源.

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

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