问题
In Java, \' denotes a single quotation mark (single quote) character, and \" denotes a double quotation mark (double quote) character.
So, String s = "I\'m a human."; works well.
However, String s = "I'm a human." does not make any compile errors, either.
Likewise, char c = '\"'; works, but char c = '"'; also works.
In Java, which is better to use? In HTML or CSS, things like style="font-family:'Arial Unicode MS';" are more often (and for such tags, I think it's the only way to use quotation marks), but in Java, I usually saw people use escape characters like "I\'m a human."
回答1:
You don't need to escape the ' character in a String (wrapped in "), and you don't have to escape a " character in a char (wrapped in ').
回答2:
It's best practice only to escape the quotes when you need to - if you can get away without escaping it, then do!
The only times you should need to escape are when trying to put " inside a string, or ' in a character:
String quotes = "He said \"Hello, World!\"";
char quote = '\'';
来源：https://stackoverflow.com/questions/16664090/in-java-should-i-escape-a-single-quotation-mark-in-string-double-quoted