Java字符开关

Question

在 Java 中切换字符的真正简单方法是什么？假设我有以下内容:

String testString = "Hello World.";

// I know this doesn't work
testString = testString.replace('o', 'e');

我想将“e”换成“o”，我知道这行不通...请告诉我我需要做什么

Answer 1

 String testString = "Hello World.";
 String replacedString = testString.replaceAll("o", "~")
                                   .replaceAll("e","o")
                                   .replaceAll("~","e");

好吧，只要你的字符串没有~