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How to convert string of values into array?

I have a string, ie 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17. How do I get each value and convert it into an array? [1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17]. I can't find any suggestions about this method. Can help? I did try using regex, but it just simply remove ',' and make the string into one long sentence with indistinguishable value. Is it ideal to get value before and after ',' with regex and put it into []?

You could use following solution
String dummy = "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17";
String[] dummyArr = dummy.split(",");

Try this to convert string to an array of Integer.
String baseString = "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17";
String[] baseArray = baseString.split(",");
int[] myArray = new int[baseArray.length];
for(int i = 0; i < baseArray.length; i++) {
myArray[i] = Integer.parseInt(baseArray[i]);
}

Java provides method Split with regex argument to manipulate strings.
Follow this example:
String strNumbers= "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17";
String[] strNumbersArr= strNumbers.split(",");
You can convert an array of string in array of integer with Streams
int[] numbersArr = Arrays.stream(strNumbersArr).mapToInt(Integer::parseInt).toArray();

Use String.split() and you will get your desired array.
String s1="1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17";
String[] mumbers=s1.split(","); //splits the string based on comma
for(String ss:numbers){
System.out.println(ss);
}

See the working Example
String csv = "Apple, Google, Samsung";
String[] elements = csv.split(",");
List<String> fixedLenghtList = Arrays.asList(elements);
ArrayList<String> listOfString = new ArrayList<String>(fixedLenghtList);
//ouput
[Apple, Google, Samsung]

if you want an int array
String s = "1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17";
String[] split = s.split(",");
int[] result = Arrays.stream(split).mapToInt(Integer::parseInt).toArray();

get count of string with commas and split them

I am new to java . I have this String.
str="plane,cat,red,dogy";
I want to make a loop and send the data . the below is wrong but i want something similar to it.
for ( int i = 0; i>str.length; i++)
{
str=split.string(,);
// i know it wrong but I want to get the result before comma, for example first loop plane, second loop cat third loop red and so on
updatestatement(str);
}

This should be what you are looking for:
String str="plane,cat,red,dogy";
for(String subString: str.split(",")){
updatestatement(subString);
}

String[] words= str.split(",");
for (String w : words){
//Do whatever you want with each word
}

Don't use for to split. Just:
String[] parts = str.split(",");

It is very unclear what you need. But i think you are looking for this:
String[] s = str.split(",");
for ( int i = 0; i<s.length; i++)
{
// i know it wrong but I want to get the result before comma, for example first loop plane, second loop cat third loop red and so on
updatestatement(str);
}
Where updatestatement is a method in your class

The answer is simple.
String str="plane,cat,red,dogy";
String[] items = str.split(",");
System.out.println("No of items::"+items.length);
If you want to print each item,
for (String eachItem : items) {
System.out.println(eachItem);
//updateStatement(eachItem);
}

You should do it as follows :
String str="plane,cat,red,dogy";
String[]str1=str.split(",");
for ( int i = 0; i>str1.length; i++)
{
updatestatement(str1[i]);
}

String str="plane,cat,red,dogy";
String[] parts = str.split(",");
Arrays.stream(parts).forEach(System.out::println);
This solution only works with Java 8 because of the stream method. If you remove the last line it also works with other Java versions.

How can I remove all non-numeric elements from an array?

I have a String array which contains both integer and non-integer elements, and I need to remove all the non-integer elements of that array.
Now I am only able to remove the non-integer content in a single string, but I need to remove the entire non-integer elements in an array.
My snippet as follows
String str = "a12.334tyz.78x";
str = str.replaceAll("[^\\d.]", "");
Can anyone help me to achieve it?

You can achieve it by below code
Pattern p = Pattern.compile("\\d*");
String [] array=new String[]{"23","33.23","4d","ff"};
List<String> lst=new ArrayList<String>();
for (int i=0; i<array.length; i++) {
if(p.matcher(array[i]).matches()){
lst.add(array[i]);
}
}
System.out.println(""+lst);

Your original code is this:
String str = "a12.334tyz.78x";
str = str.replaceAll("[^\\d.]", "");
First, if you need to remove all non-integer character, you need to change your regex from "[^\d.]" to "[^\d]".
Yours will not remove dots character.
Then, you said:
Now I am only able to remove the non-integer content in a single
string, but I need to remove the entire non-integer elements in an
array.
Maybe I'm not getting this right, but isn't just a matter of looping while doing the same thing ? You didn't show us any code with loops, but perhaps your true problem is reassigning the modified value to the array ?
try this:
for(int i=0;i<strArray.length;i++){
strArray[i] = strArray[i].replaceAll("[^\\d]", "");
}
MAYBE you were doing something like this ? (this does not work):
for(String str: strArray){
str = str.replaceAll("[^\\d]", "");
}
That doesn't work because the modified string is not reassigned to the array, it is assigned to the new variable 'str'. So this code does not update the value pointed by the array.

replace all numbers - str = str.replaceAll("\\d", "");
replace all non-numbers - str = str.replaceAll("[^\\d]", "");
to do so in an array, iterate over the Array and do the replacment.

To remove all the non-integer values form a string you can try the following:
public boolean isInt(String s)
{
for(int i = 0; i < s.length(); i++)
{
try
{
Integer.parseInt(String.valueOf(s.charAt(i)));
}catch(NumberFormatException e)
{
return false;
}
}
return true;
}
Then you can iterate your array and remove the non-integer elements like this
for(int i = 0; i < arr.length; i++)
{
if(isInt(arr[i]))//remove the element
}

It would probably be easier to remove elements from a list than from an array. However, you can stream the elements of the array, remove invalid elements with flatMap, and then convert back to an array.
When using flatMap, each element in the input can produce zero, one, or many elements in the output, so we map the valid ones to singleton streams containing just that element, and the invalid ones to empty streams, thus removing them from the result.
String[] result = Arrays.stream(input)
.flatMap(a -> Pattern.matches("\\d+", a)?
Stream.of(a) : Stream.empty())
.toArray(String[]::new);

If your regex is working correctly, you already solved most of your problem. You only need to use your code in a for loop. You can try the code below:
public String[] removeNonIntegersFromArray(String[] array){
ArrayList<String> temp = new ArrayList<String>();
for (int i=0; i<array.length; i++) {
String str = array[i];
if(!str.matches(".*[^\\d]+.*")){
temp.add(str);
}
}
String[] result = new String[temp.size()];
result = (String[]) temp.toArray(new String[temp.size()]);
return result;
}
Edit: I refactored the code as it will delete whole array element which has non-integer.

Here is an idea,
Instead of replacing all non-int number, to find all integer and add them to a new string.
for(int i=0;i<str.length();i++)
{
if(Character.isDigit(str.charAt(i)))
new_str.append(str.charAt(i));
}

arrays splitting strings java

I'm sure this is a fairly easy question for someone but I cant work out the best way to do it as a relative beginner.
I am splitting a large file (the string temp) into about a 100 strings and setting it as an array, but I don't know the exact number of strings.
String[] idf = temp.split("===========");
String class1 = idf[0];
String class2 = idf[1];
String class3 = idf[1];
etc etc..
What is the best way to ensure that I can split all the strings and store them in an array?
Any suggestions or pointers would be most appreciated thanks!

You can do it like this:
String list = "hey there how are you";
String[] strarray = list.split("\\s+");
for (String str: strarray)
{
System.out.print(str);
}

Probably you want to iterate over your String array.
You can do it like that:
for(String s : idf) {
//operate on s here
}

Use for-each to get elements from array.
Please look at oracle official site for for-each loop.
Consider below code.
String tempString = "";
String regex = "";
String[] temparray = tempString.split(regex);
for (String temp : temparray)
{
System.out.println(temp);
}

Java String to Array

I want to evaluate String like "[1,5] [4,5] [10,6]" in in array.
I'm not quite familiar with the Java regex and the syntax.
String game = "[1,5] [4,5] [10,6]"
Pattern splitter = Pattern.compile("\\[|,|\\]");
splitter.matcher(game);
public String [] gameArray = null;
gameArray = splitter.split(game);
I want to to iterate over each pair of array such as : [0][0] => 1; [0][1] => 5

If you put
StringTokenizer st = new StringTokenizer(game, "[,] ");
while (st.hasMoreTokens())
{
currentNumber = Integer.parseInt(st.nextToken());
// fill array with it
}
It should be what you need, if I understood well

For this purpose you need to split your string.
first of all you need to split on space and after that you need to split on ,(comma).and your third step will be remove brackets So at the end you will get you string into array.

Try,
String game = "[1,5] [4,5] [10,6]";
String[] arry=game.substring(1, game.length()-1).split("\\] +\\[");
List<String[]> twoDim=new ArrayList<>();
for (String string : arry) {
String[] twoArr=string.split(",");
twoDim.add(twoArr);
}
String[][] twoArr=twoDim.toArray(new String[0][0]);
System.out.println(twoArr[0][0]); // 1
System.out.println(twoArr[0][1]); // 5