Remove [ ] from string

Question

How to remove [ ] from my output?

String omega_str[][]  ; 
StringBuilder sb=new StringBuilder();
         for (String[] row:omega_str)
                 sb.append(Arrays.toString(row));

    String text=sb.toString();  
        System.out.println("Text : "+text);

My output is:

[-0.06409677515180673][0.12516724483856012][-0.06188844693840026][0.1542289929525214][-0.06603595481351604][0.07823062287735344][0.10161817634744892]

expected output

-0.06409677515180673 0.12516724483856012 -0.06188844693840026 0.1542289929525214 -0.06603595481351604 0.07823062287735344 0.10161817634744892 

How to do this?

Answer 1

Change

String text=sb.toString();  

to

String text=sb.toString().replace('[', ' ').replace(']', ' ');  

Answer 2

You should not first produce something, then remove it. The [...] is the result of Arrays.toString. You better loop through the subarrays and print the values to the string builder.

BTW, it looks like you have only ever a single value in the subarray. (This raises the question, if you really need a 2-dimensional array.) Anyway, if you know that there is only a single value, you do not even need a loop, just

sb.append(' ');
sb.append(row[0]);

Answer 3

Use regex with replaceAll

 String str="[-0.06409677515180673][0.12516724483856012]"
            + "[-0.06188844693840026][0.1542289929525214]"
            + "[-0.06603595481351604][0.07823062287735344]"
            + "[0.10161817634744892]";
 str=str.replaceAll("[\\[|\\]]", " ");
 System.out.println(str);

Output:

-0.06409677515180673 0.12516724483856012 -0.06188844693840026 0.1542289929525214 -0.06603595481351604 0.07823062287735344 0.10161817634744892

Answer 4

Simply use a substring():

yourString.substring(1, yourString.length() - 1);

Answer 5

Skip [ ] before add it into StringBuilder

String str= Arrays.toString(row);
str= str.substring(1,str.length()-1); 
sb.append(str);

Answer 6

Calling .toString() to an array will always generate such output, so I'd suggest you to replace "[]"with an empty string "" after calling .toString() on an array like this:

line.replace("[", "").replace("]", "");

but it's a good solution only for short strings due to performance issuses.

Answer 7

try replaceAll with escape characters:

String str = "[-0.06409677515180673][0.12516724483856012][-0.06188844693840026][0.1542289929525214][-0.06603595481351604][0.07823062287735344][0.10161817634744892]";
str = str.replaceAll("\\[", "").replaceAll("\\]","");

Answer 8

this will do the trick for you.

for (String[] row:omega_str) {
  for(String val : row) {
      sb.append(val + " ");
  }
}

String text=sb.toString();  
System.out.println("Text : "+text);

as @Ingo suggested don't produce something which you want to delete

Answer 9

I believe that using regex in order to remove what I don't like from the toString method is not a good approach to the problem. I will simply create a method in your class with a good name (i.e. print....) like this:

public static void printArray(String[][] array) {
        System.out.print("Text :");
        for (String[] row : array)
            for (String element : row)
                System.out.print(" " + element);
    }

And simply call:

printArray(omega_str);

Using this solution you don't have to use either the StringBuilder instance.

Ciao!