Java 创建具有相对路径的 URL 对象
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/4247736/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
creating a URL object with a relative path
提问by Anto
I am creating a Swing application with a JEditorPane that should display an HTML file named url1.htmlstored locally in the pagefolder in the root folder of the project.
我正在创建一个带有 JEditorPane 的 Swing 应用程序，该应用程序应该显示一个名为url1.html的 HTML 文件，该文件本地存储在项目根文件夹的页面文件夹中。
I have instantiated the following String object
我已经实例化了以下 String 对象
final String pagePath = "./page/";
and in order to be displayed by the JEditorPane pane I have created the following URL object:
为了在 JEditorPane 窗格中显示，我创建了以下 URL 对象：
URL url1 = new URL("file:///"+pagePath+"url1.html");
However when the setPage method is called with thecreated URL object as a parameter
但是当 setPage 方法以创建的 URL 对象作为参数被调用时
pagePane.setPage(url1);
it throws me a java.io.FileNotFoundException error
它给我一个 java.io.FileNotFoundException 错误
It seems that there is something wrong with the way url1has been constructed. Anyone knows a solution to this problem?
url1 的构造方式似乎有问题。有谁知道这个问题的解决方案？
采纳答案by khachik
The solution is to find an absolute path to url1.htmlmake an object of java.io.Fileon it, and then use toURI().toURL()combination:
解决办法是找到一个绝对路径url1.html，java.io.File在上面创建一个对象，然后使用toURI().toURL()组合：
URL url1 = (new java.io.File(absolutePathToHTMLFile)).toURI().toURL();
Assuming if the current directory is the root of page, you can pass a relative path to File:
假设当前目录是 的根目录，则page可以将相对路径传递给File：
URL url1 = (new java.io.File("page/url1.html")).toURI().toURL();
or
或者
URL url1 = (new java.io.File(new java.io.File("page"), "url1.html")).toURI().toURL();
But this will depend on where you run the application from. I would make it taking the root directory as a command-line argument if it is the only configurable option for the app, or from a configuration file, if it has one.
但这将取决于您从何处运行应用程序。如果根目录是应用程序的唯一可配置选项，或者来自配置文件（如果有），我会将其作为命令行参数。
The another solution is to put the html file as a resource into the jar file of your application.
另一种解决方案是将 html 文件作为资源放入应用程序的 jar 文件中。
回答by Salman Paracha
I would try the following
我会尝试以下
URL url = new URL("file", "", pagePath+"url1.html");
I believe by concatenating the whole string, you are running into problems. Let me know, if that helped
我相信通过连接整个字符串，您会遇到问题。让我知道，如果这有帮助
回答by jcadcell
To load a resource from the classpath (as khachik mentioned) you can do the following:
要从类路径加载资源（如 khachik 所述），您可以执行以下操作：
URL url = getClass().getResource("page/url1.html");
or from a static context:
或从静态上下文：
URL url = Thread.currentThread().getContextClassLoader().getResource("page/url1.html");
So in the case above, using a Maven structure, the HTML page would be at a location such as this:
因此，在上述情况下，使用 Maven 结构，HTML 页面将位于如下位置：
C:/myProject/src/main/resources/page/url1.html
