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cannot split a specific kind of strings using Java

I am working in Java. I have list of parameters stored in a string which is coming form excel. I want to split it only at starting hyphen of every new line. This string is stored in every excel cell and I am trying to extract it using Apache poi. The format is as below:
String text =
"- I am string one\n" +
"-I am string two\n" +
"- I am string-three\n" +
"with new line\n" +
"-I am string-four\n" +
"- I am string five";
What I want
array or arraylist which looks like this
[I am string one,
I am string two,
I am string-three with new line,
I am string-four,
I am string five]
What I Tried
I tried to use split function like this:
String[] newline_split = text.split("-");
but the output I get is not what I want
My O/P
[, I am string one,
I am string two,
I am string, // wrong
three // wrong
with new line, // wrong
I am string, // wrong!
four, // wrong!
I am string five]
I might have to tweak split function a bit but not able to understand how, because there are so many hyphens and new lines in the string.
P.S.
If i try splitting only at new line then the line - I am string-three \n with new line breaks into two parts which again is not correct.
EDIT:
Please know that this data inside string is incorrectly formatted just like what is shown above. It is coming from an excel file which I have received. I am trying to use apache poi to extract all the content out of each excel cell in a form of a string.
I intentionally tried to keep the format like what client gave me. For those who are confused about description inside A, I have changed it because I cannot post the contents on here as it is against privacy of my workplace.

You can
remove line separators (replace it with space) if they don't have - after it (in next line): .replaceAll("\\R(?!-)", " ") should do the trick
\R (written as "\\R" in string literal) since Java 8 can be used to represent line separators
(?!...) is negative-look-ahead mechanism - ensures that there is no - after place in which it was used (will not include it in match so we will not remove potential - which ware matched by it)
then remove - placed at start of each line (lets also include followed whitespaces to trim start of the string). In other words replace - placed
after line separators: can be represented by "\\R"
after start of string: can be represented by ^
This should do the trick: .replaceAll("(?<=\\R|^)-\\s*","")
split on remaining line separtors: .split("\\R")
Demo:
String text =
"- I am string one\n" +
"-I am string two\n" +
"- I am string-three\n" +
"with new line\n" +
"-I am string-four\n" +
"- I am string five";
String[] split = text.replaceAll("\\R(?!-)", " ")
.replaceAll("(?<=\\R|^)-\\s*","")
.split("\\R");
for (String s: split){
System.out.println("'"+s+"'");
}
Output (surrounded with ' to show start and end of results):
'I am string one'
'I am string two'
'I am string-three with new line'
'I am string-four'
'I am string five'

This is how I would do:
import java.util.*;
public class MyClass {
public static void main(String args[]) {
String A = "- I am string one \n" +
" -I am string two\n" +
" - I am string-three \n" +
" with new line\n" +
" -I am string-four\n" +
"- I am string five";
String[] s2 = A.split("\r?\n");
List<String> lines = new ArrayList<String>();
String line = "";
for (int i = 0; i < s2.length; i++) {
String ss = s2[i].trim();
if (i == 0) { // first line MUST start with "-"
line = ss.substring(1).trim();
} else if (ss.startsWith("-")) {
lines.add(line);
ss = ss.substring(1).trim();
line = ss;
} else {
line = line + " " + ss;
}
}
lines.add(line);
System.out.println(lines.toString());
}
}
I hope it helps.
A little explanation:
I will process line by line, trimming each one.
If it starts with '-' it means the end of the previous line, so I include it in the list. If not, I concatenate with the previous line.

looks as if you are splitting the FIRST - of each line, so you need to remove every instance of a "newline -"
str.replace("\n-", '\n')
then Remove the initial "-"
str = str.substring(1);

Unwanted elements appearing when splitting a string with multiple separators in Java

I have a string from which I need to remove all mentioned punctuations and spaces. My code looks as follows:
String s = "s[film] fever(normal) curse;";
String[] spart = s.split("[,/?:;\\[\\]\"{}()\\-_+*=|<>!`~##$%^&\\s+]");
System.out.println("spart[0]: " + spart[0]);
System.out.println("spart[1]: " + spart[1]);
System.out.println("spart[2]: " + spart[2]);
System.out.println("spart[3]: " + spart[3]);
System.out.println("spart[4]: " + spart[4]);
But, I am getting some elements which are blank. The output is:
spart[0]: s
spart[1]: film
spart[2]:
spart[3]: fever
spart[4]: normal
My desired output is:
spart[0]: s
spart[1]: film
spart[2]: fever
spart[3]: normal
spart[4]: curse

Try with this:
public static void main(String[] args) {
String s = "s[film] fever(normal) curse;";
String[] spart = s.split("[,/?:;\\[\\]\"{}()\\-_+*=|<>!`~##$%^&\\s]+");
for (String string : spart) {
System.out.println("'"+string+"'");
}
}
output:
's'
'film'
'fever'
'normal'
'curse'

I believe it is because you have a Greedy quantifier for space at the end there. I think you would have to use an escape sequence for the plus sign too.

String spart = s.replaceAll( "\\W", " " ).split(" +");

How to remove commas at the end of any string

I have Strings "a,b,c,d,,,,, ", ",,,,a,,,,"
I want these strings to be converted into "a,b,c,d" and ",,,,a" respectively.
I am writing a regular expression for this. My java code looks like this
public class TestRegx{
public static void main(String[] arg){
String text = ",,,a,,,";
System.out.println("Before " +text);
text = text.replaceAll("[^a-zA-Z0-9]","");
System.out.println("After " +text);
}}
But this is removing all the commas here.
How can write this to achieve as given above?

Use :
text.replaceAll(",*$", "")
As mentioned by #Jonny in comments, can also use:-
text.replaceAll(",+$", "")

Your first example had a space at the end, so it needs to match [, ]. When using the same regular expression multiple times, it's better to compile it up front, and it only needs to replace once, and only if at least one character will be removed (+).
Simple version:
text = text.replaceFirst("[, ]+$", "");
Full code to test both inputs:
String[] texts = { "a,b,c,d,,,,, ", ",,,,a,,,," };
Pattern p = Pattern.compile("[, ]+$");
for (String text : texts) {
String text2 = p.matcher(text).replaceFirst("");
System.out.println("Before \"" + text + "\"");
System.out.println("After \"" + text2 + "\"");
}
Output
Before "a,b,c,d,,,,, "
After "a,b,c,d"
Before ",,,,a,,,,"
After ",,,,a"

Split string after n amount of digits occurrence

I'm parsing some folder names here. I have a program that lists subfolders of a folder and parses folder names.
For example, one folder could be named something like this:
"Folder.Name.1234.Some.Info.Here-ToBeParsed"
and I would like to parse it so name would be "Folder Name". At the moment I'm first using string.replaceAll() to get rid of special characters and then there is this 4-digit sequence. I would like to split string on that point. How can I achieve this?
Currently my code looks something like this:
// Parsing string if regex p matches folder's name
if(b) {
//System.out.println("Folder: \" " + name + "\" contains special characters.");
String result = name.replaceAll("[\\p{P}\\p{S}]", " "); // Getting rid of all punctuations and symbols.
//System.out.println("Parsed: " + name + " > " + result);
// If string matches regex p2
if(b2) {
//System.out.println("Folder: \" " + result + "\" contains release year.");
String parsed_name[] = result.split("20"); // This is the line i would like to split when 4-digits in row occur.
//System.out.println("Parsed: " + result + " > " + parsed_name[0]);
movieNames.add(parsed_name[0]);
}
Or maybe there is even easier way to do this? Thanks in advance!

You should keep it simple like this:
String name = "Folder.Name.1234.Some.Info.Here-ToBeParsed";
String repl = name.replaceFirst( "\\.\\d{4}.*", "" ).
replaceAll( "[\\p{P}\\p{S}&&[^']]+", " " );
//=> Folder Name
replaceFirst is removing everything after a DOT and 4 digits
replaceAll is replacing all punctuation and space (except apostrophe) by a single space

How to replace multiple spaces and newlines with one blank line

How to remove multiple spaces and newlines in a string, but preserve at least one blank line for each group of blank lines.
For example, change:
"This is
a string.
Something."
to
"This is
a string.
Something."
I'm using .trim() to strip whitespace from the beginning and end of a string, but I couldn't find anything for removing multiple spaces and newlines in a string.
I would like to keep just one whitespace and one newline.

The one-line solution to remove multiple spaces/newlines, but preserve at least one blank line from multiple blank lines:
str = str.replaceAll("(?m)(^ *| +(?= |$))", "").replaceAll("(?m)^$([\r\n]+?)(^$[\r\n]+?^)+", "$1");
Each individual line is trimmed too.
Here's some test code:
String str = " This is\r\n " +
"\r\n" +
" \r\n " +
" \r \n \n " +
"\r\n" +
" a string. ";
str = str.trim().replaceAll("(?m)(^ *| +(?= |$))", "").replaceAll("(?m)^$([\r\n]+?)(^$[\r\n]+?^)+", "$1");
System.out.println(str);
Output:
This is
a string.

The previous advice will trim all whitespace, including the linefeeds and replace them with a single space.
text.replaceAll("\\n\\s*\\n", "\\n").replaceAll("[ \\t\\x0B\\f]+", " ").trim());
First it replaces any instances of linefeeds with only whitespace between them with a single linefeed, then it trims down any other whitespace to a single space ignoring linefeeds.

Here is what I came up with after a bit of testing...
public String keepOneWS(String str) {
Pattern p = Pattern.compile("(\\s+)");
Matcher m = p.matcher(str);
Pattern pBlank = Pattern.compile("[ \t]+");
String newLineReplacement = System.getProperty("line.separator") +
System.getProperty("line.separator");
StringBuffer sb = new StringBuffer();
while (m.find()) {
if(pBlank.matcher(m.group(1)).matches()) {
m.appendReplacement(sb, " ");
} else {
m.appendReplacement(sb, newLineReplacement);
}
}
m.appendTail(sb);
return sb.toString().trim();
}
public void testKeepOneWS() {
String str = " This \t is\r\n " +
"\r\n" +
" \r\n " +
" \r \n \t \n " +
"\r\n" +
" a \t string. \t ";
String expected = "This is" + System.getProperty("line.separator")+
System.getProperty("line.separator") + "a string.";
String actual = keepOneWS(str);
System.out.println("'" + actual + "'");
assertEquals(expected, actual);
}
After a goup of whitespace is captured, it is checked whether it consists only of spaces, if yes then that goup is replaced by one single space, otherwise the goup consits of spaces and line terminators, in this case the group is replaced by one line terminator.
The output is:
'This is
a string.'