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how to remove multiple characters by their indice from a string in java? [closed]

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How can I remove multiple characters by their index from a string. I thought to use StringBuilder's deleteCharAt function. But if I delete char one by one, I will not keep track the right index.
For example :
String test = "0123456789"
int[] removingIndice = int[] {2, 4, 0};
// remove character from string
// result = "1356789"

Create a new string builder,
iterate on string, add elements to builder if its index not in the array
StringBuilder sb = new StringBuilder("");
for(int i = 0; i< test.length; i++){
if( !ArrayUtils.contains(removingIndice, i))
{
sb.append(test.charAt(i));
}
}
test = sb.toString();

String is immutable in Java, so you will need to create a new String with characters at positions 0,2,4 removed. As one option, you may use StringBuilder for that, as answered here: How to remove single character from a String

I think, you need to redesign the task:
"new string must contains all characters except ..."
Now, seems weak initial data structure and the goal.

All combinations of ArrayList<ArrayList<String>> Lists in JAVA [closed]

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I need help with a implementation of a function that gives me all combinations of ArrayList<ArrayList<String>> (not List<List<String>>) List in fix order.
An Example for what I need:
From:
List1:[1,2]
List2:[3,4]
List3:[5,6]
To:
String 1 "1,3,5"
String 2 "1,3,6"
String 3 "1,4,5"
String 4 "1,4,6"
String 5 "2,3,5"
String 6 "2,3,6"
String 7 "2,4,5"
String 8 "2,4,6"
All Strings in ArrayList<String> Object
Please help me, I have no idea how to implement it.
PS: The size of ArrayList<ArrayList<String>> is variable.
PSS: ...and the size from the ArrayList lists are variable.

After little changes from the old rev it works now (ArrayIndexOutOfBoundsException and deleting to much on result):
void generate(ArrayList<ArrayList<String>> lists,
ArrayList<String> result, int index) {
if (index >= lists.size()) {
System.out.println(String.valueOf(result));
return;
}
ArrayList<String> list = lists.get(index);
for (int i = 0; i < list.size(); i++) {
result.add(list.get(i));
generate(lists, result, index + 1);
result.remove(result.size() - 1);
}
}
}

I want to split into `String and `int` arrays Java [closed]

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I have text data and I want to split into String and int arrays Java
String text = "one1two20three300four4000";
Desired output:
String str[] = "one","two","three","four";
int num[] = 1,20,300,4000;

This one will work for you in Java :
public static void main(String[] args) {
String text = "one1two20three300four4000";
String arr1[] = text.replaceFirst("^\\d+", "").split("\\d+");
String arr2[] = text.replaceFirst("^\\D+", "").split("\\D+");
System.out.println(Arrays.toString(arr1));
System.out.println(Arrays.toString(arr2)); // parse each value as an in using Streams (preferably) or a loop.
}
O/P :
[one, two, three, four] [1, 20, 300, 4000]
PS : In java 8 Use int[] arr2Int = Arrays.stream(arr2).mapToInt(Integer::parseInt).toArray(); to convert your String array to int array.

How to convert ArrayList of Strings to ints, so they can be added? [closed]

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I am trying to convert each String in an ArrayList to int so then I can add them,
asuma is an ArrayList containing String
I need to iterate over this ArrayList to convert String to int
for (int i = 0; i <=asuma.size(); i++) {
and then I need to add the integers. How do I do it?

I suspect that the ArrayList you are referring to is asuma and that it is an ArrayList<String>. In that case, you can do this:
for (String s : asuma) {
int valorFinal = Integer.parseInt(s);
}

I think u try that:
for (int i = 0; i <=asuma.size(); i++) {
int valorFinal = Integer.parseInt(asuma.get(i));
}

String Array to Integer Array Java [closed]

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I have a string array for an app I am making. It loads an EditText, so I will instead create a dummy one.
String[] s = ["1","2","3"];
How would I change String s into an integer array, such as Int i?
Int[] i = [1,2,3];
I have tried Integer.parseInt on the string array but it does not work. Does anyone know how to convert string arrays into integer arrays?

Something like the following should work:
string[] s = ["1","2","3"];
int[] i = new int[s.length()];
for (int j = 0; j < s.length(); j++)
i[j] = Integer.parseInt(s[j]);