have the source string
str = "one
two
three
four
five
six
seven
eight
nine"
I want to get an array of strings
String[] mas;
mas[0] = "one
two
three
four"
mas[1] =five
six
seven
eight"
mas[2] ="nine"
I want a function that will be out of my line to do an array of strings. And in each row of the array should get 4 or 6 or N lines from the original string
Use String.split() with a regex \\s+ (or \n+ for example, depending on what you exactly want).
You can concat 2 or more strings if needed, but after you have the array using split() - it should be fairly easy, give it a try!
good luck. Feel free to ask any question if you are having troubles implementing the 2nd part.
EDIT: seems like you are having troubles with concatting the strings. This shou;d be done with simple iteration and a StringBuilder:
int SIZE = 4;
String[] arr = str.split("\\s+");
List<String> res = new ArrayList<>();
StringBuilder sb = new StringBuilder();
for (int i = 0; i < arr.length; i++) {
sb.append(arr[i]).append('\n');
if (i % SIZE == SIZE-1) {
res.add(sb.toString());
sb = new StringBuilder();
}
}
if (sb.length() != 0) res.add(sb.toString());
System.out.println(res);
}
Note that res is a List<String>, if you want it as an array, you can always use the toArray() method.
StringBuilder?If you want to split into an array with one line per array element, then String.split should do this; see @amit's answer.
If you want to split into an array with N lines per array element (as per your example), there is no standard library class / method to do this. And as far as I'm aware there is no method in any of the commonly used 3rd-party libraries to do this.
So what you could do is one of the following:
Matcher.find(...) to match / step through the line breaks, and every N times, you call String.substring(...) to pull out a group of lines.(It might also be possible to produce a gnarly regex with a complicated positive look-behind that served to effectively count N line breaks. However, that is (IMO) "nasty" ...)
@Test
public void test(){
String str = "one\ntwo\nthree\nfour\nfive\nsix\nseven\neight\nnine";
int number = 52;
String[] strArr = getArray(str, 52);
}
String[] getArray(String str, int number){
int nb = (int) Math.ceil(number / 20);
String[] strSplit = str.split("\n");
String[] strArr = new String[nb+1];
int cursor = 0;
for (int colNumberForFinalArray=0; colNumberForFinalArray<nb+1; colNumberForFinalArray++){
strArr[colNumberForFinalArray] = "";
int countElts = 20;
if(colNumberForFinalArray == nb){
countElts = number % 20;
}
for(int i = cursor; i< cursor+countElts ; i++){
strArr[colNumberForFinalArray] += strSplit[i];
if(i < cursor+countElts-1){
strArr[colNumberForFinalArray] += "\n";
}
}
cursor = cursor+countElts;
}
return strArr;
}
Call this method and you will get an Array of your string
public String[] stringSplitter(String input){
String[] splitStr = input.split("\\s+");
return splitStr ;
}
Call the following method to organize your result in groups of four
public ArrayList<String> stringGrouping(String[] input){
int iter = 4;
ArrayList<String> result = new ArrayList<String>();
for(int i=0; i<input.length(); i++){
String temp="";
while(iter>0){
temp.append(input.get(i));
}
result.add(temp);
iter =4;
}
Description:
-The method split take a regex input to detect the char that you want to divide with and return an Array of splitted words.
-The regex "\s+" detects any occurrence of One or more spaces.
I hope it helps
