Question

我正在解析此位置的基本文件： /Users/haddad/development/fspc/content/2017.dev/src/agency/individual/integration/src/forms/print.xml

从那个档案中，我解析出来： ../../../../include/masking.xml

因此，相对路径来自我从（基本文件）

解析出来的文件的上下文

如何从该相对路径构建文件对象，以便我可以读取它的内容？

Answer 1

由于您标记了nio，因此Path类可以轻松实现此目标。您只需致电resolveSibling()和normalize()。

String main = "/Users/haddad/development/fspc/content/2017.dev/src/agency/individual/integration/src/forms/print.xml";
String ref = "../../../../include/masking.xml";

System.out.println(Paths.get(main));
System.out.println(Paths.get(main).resolveSibling(ref));
System.out.println(Paths.get(main).resolveSibling(ref).normalize());

或者：

System.out.println(Paths.get(main));
System.out.println(Paths.get(main, ref));
System.out.println(Paths.get(main, ref).normalize());

输出

\Users\haddad\development\fspc\content\2017.dev\src\agency\individual\integration\src\forms\print.xml
\Users\haddad\development\fspc\content\2017.dev\src\agency\individual\integration\src\forms\..\..\..\..\include\masking.xml
\Users\haddad\development\fspc\content\2017.dev\src\agency\include\masking.xml

^{注意：我在Window机器上运行它，所以我当然得到了反斜杠}

如果您更喜欢旧的File对象，则使用双参数构造函数，并调用getCanonicalFile()。

System.out.println(new File(main));
System.out.println(new File(main, ref));
System.out.println(new File(main, ref).getCanonicalFile());

输出

\Users\haddad\development\fspc\content\2017.dev\src\agency\individual\integration\src\forms\print.xml
\Users\haddad\development\fspc\content\2017.dev\src\agency\individual\integration\src\forms\print.xml\..\..\..\..\include\masking.xml
C:\Users\haddad\development\fspc\content\2017.dev\src\agency\individual\include\masking.xml

Answer 2

您可以使用subpath()来保留您感兴趣的路径部分，以便与resolve()结合使用以添加新路径：

public static void main(String[] args) {

    Path printXmlPath = Paths.get("/Users/haddad/development/fspc/content/2017.dev/src/agency/individual/integration/src/forms/print.xml");

    Path maskingXmlPath = printXmlPath.subpath(0, printXmlPath.getNameCount() - 5)
                                      .resolve("include/masking.xml");

    System.out.println(maskingXmlPath);
}

用户\ Haddad的\发展\ FSPC \内容\ 2017.dev \ SRC \机构\包括\ masking.xml

如何从File中的相对路径构造文件

2 个答案: