java - How to extract part of a string?

Question

Possible Duplicate:
How to get file name without the extension?

I have a list of xml files and I'm trying to return just the file name without the extension. For example, if I have:

String filename = "hello.xml";

How would I return just "hello" with the fact the file names vary?

Answer 1

String filenameSansExt = filename.replaceAll("\\.[^.]*", "");

Answer 2

使用substring()比使用replaceAll()正则表达式或任何其他正则表达式更有效。

两个答案都不太令人满意：

• 正则表达式太慢，但正确
• lastIndexOf()'.'不存在时会抛出异常（索引-1）

正确答案必须检查索引lastIndexOf()。

Answer 3

您可以在 java 中对字符串使用 substring 函数。您将从 0（字符串的开头）开始并在第 4 个到最后一个字符（“。”）之前结束

String filename = "hello.xml";
String filename2 = filename.substring(0, filename.length() - 4);