Question

java 中split("",-1)函数 里面的 -1 代表什么

Answer 1

Splits this string around matches of the given regular expression.
The array returned by this method contains each substring of this string that
is terminated by another substring that matches the given expression or is
terminated by the end of the string. The substrings in the array are in the
order in which they occur in this string. If the expression does not match any
part of the input then the resulting array has just one element, namely this
string.
The limit parameter controls the number of times the pattern is
applied and therefore affects the length of the resulting array. If the limit
n is greater than zero then the pattern will be applied at most
n - 1 times, the array's length will be no greater than n, and the
array's last entry will contain all input beyond the last matched delimiter. If
n is non-positive then the pattern will be applied as many times as
possible and the array can have any length. If n is zero then the pattern
will be applied as many times as possible, the array can have any length, and
trailing empty strings will be discarded.
The string "boo:and:foo", for example, yields the following results
with these parameters:
RegexLimitResult
: 2 { "boo", "and:foo" }
: 5 { "boo", "and", "foo" }
: -2 { "boo", "and", "foo" }
o 5 { "b", "", ":and:f", "", "" }
o -2 { "b", "", ":and:f", "", "" }
o 0 { "b", "", ":and:f" }
An invocation of this method of the form
str.split(regex, n) yields the
same result as the expression
java.util.regex.Pattern.compile(regex).split(str, n)Parameters:
regex the delimiting regular expression
limit the result threshold, as described above
Returns:
the array of strings computed by splitting this string around matches of the
given regular expression
Throws:
PatternSyntaxException
- if the regular expression's syntax is invalid
Since:
1.4
See Also:
java.util.regex.Pattern@spec
JSR-51
以上是jdk的注解，参数-1表示split次数没有限制，

Answer 2

true

Answer 3

空