如何基于换行符拆分Java字符串

Question

I have a string in java defined as below:

String numbers = null;
for (int i= 0; i < contactNumberList.size();i++)
{
    numbers = contactNumberList.get(i) + "\n" + numbers;
}

where contactNumberList contains four items as : 9891, 3432, 5432, 9890. So after the loop i have numbers string as: 9890\\n5432\\n3432\\n9891\\nnull

Then i passed the above string through following APIs.

String toUnicodeEncoded = StringEscapeUtils.escapeJava(numbers);
toUnicodeEncoded = StringEscapeUtils.escapeXml10(toUnicodeEncoded);

Now when i try to print the string toUnicodeEncoded character by character as below:

for (int i =0;i<toUnicodeEncoded.length();i++)
{
   Logger.log("chat at  "+i + " = "+(toUnicodeEncoded.charAt(i)));
}

It gives :

char at 0 = 9
char at 1 = 8
char at 2 = 9
char at 3 = 0
char at 4 = \
char at 5 = n

and so on .

My point is "\\n" became two characters \\ and n . Now i wanted to split the string toUnicodeEncoded based on "\\n" using the following APIs:

String lines[] = toUnicodeEncoded.split("\\n");

But its not able to split it because now "\\n" has become \\ and n. How do i split toUnicodeEncoded string by "\\n" or new line character.

BAsically i want the output as :

9890
5432
3432
9891
null

ie all four numbers . How do i do it.

Answer 1

When we split your string with \\n it is giving expected output. But it is better to use System.getProperty("line.separator") instead of \\n

String s="9890\n5432\n3432\n9891\nnull";
s = StringEscapeUtils.escapeJava(s);
s= StringEscapeUtils.escapeXml10(s);

for (String number:s.split("\n")) {
    System.out.println(number);
}

result

9890
5432
3432
9891
null

Answer 2

使用这个，应该做的把戏

String.split("[\\r\\n]+")

Answer 3

Thanks everybody for replying. But i got it working using following approach:

String pattern = Pattern.quote("\\" + "n");
String lines[] = toUnicodeEncoded.split(pattern);