Java Regex 的Mather类

今天在写代码，单元测试有个对于文件目录替换的正则表达式在windows测试没有通过。
看看原来代码好像没有问题：
File f = new File("d://1//1.txt");
String source = "d://1";
String dest = "d://2";
String absolutePath = f.getAbsolutePath();
String reg = source;
String rep = dest;
String newPath = absolutePath.replaceAll(reg, rep);
期望newPath : d://2//1.txt 但是还是 d://1//1.txt。

看了replaceAll的javadoc，里面有
Note that backslashes (/) and dollar signs ($) in the replacement string may cause the results to be different than if it were being treated as a literal replacement string; seeMatcher.replaceAll. UseMatcher.quoteReplacement(java.lang.String)to suppress the special meaning of these characters, if desired.

顿时豁然开朗。
修改代码：
File f = new File("d://1//1.txt");
String source = "d://1";
String dest = "d://2";
String absolutePath = f.getAbsolutePath();
String reg = Matcher.quoteReplacement(source);
String rep = Matcher.quoteReplacement(dest);
String newPath = absolutePath.replaceAll(reg, rep);

结果newPath : d://2//1.txt。