java - 如何从文件中的相对路径构造文件

Question

我正在此位置解析基本文件:/Users/haddad/development/fspc/content/2017.dev/src/agency/individual/integration/src/forms/print.xml

从该文件中，我解析出:../../../../include/masking.xml

因此，相对路径来 self 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造一个文件对象，以便我可以读取它的内容？

Answer 1

由于您标记了 nio，Path类使这变得容易。您只需调用 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 Windows 机器上运行了这个，所以我当然得到了反斜杠}

<小时/>

如果您喜欢旧的 File对象，您使用两个参数构造函数，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