Java replace & replaceAll

Java字符串中需要对一些字符进行替换，用到最多的是replace和replaceAll两个方法。这两个方法在使用的时候需要注意：

replace：

public String replace (CharSequence target, CharSequence replacement)

Added in API level 1

Returns a copy of this string after replacing occurrences of target replaced with replacement. The string is processed from the beginning to the end.

Throws

NullPointerException
if
target or replacement is null.

从上面的注释可以看出，该方法是将替换以后的字符拷贝返回的，原字符串并没有发生改变。