How to insert one string into the middle of another string? [duplicate]

Answer 1

You don't need to use StringBuilder or any other complex method to do this. Here is the simplest way to achieve this. In this method I have just used the simple String methods.

import java.util.Scanner;

class Insert
{
    public static void main(String[] args)
    {
        System.out.println("Enter First String");
        Scanner scan = new Scanner (System.in);
        String str = scan.next();
        System.out.println("Enter Second String");
        Scanner scan2 = new Scanner (System.in);
        String str1 = scan2.next();
        int i = str.length();
        int j = i/2;

        if (i % 2 == 0)                    //Condition For Even
        {
            System.out.println(str.substring(0,j) + str1 + str.substring(j-1,(str.length() - 1)));
        }
        else 
        {
            System.out.println(str.substring(0,j) + str1 + str.substring(j,(str.length() - 0)));
        }
    }
}

Answer 2

You have to concat two substrings of the first string onto the ends of the second.

// put the marble in the bag
public static String insert(String bag, String marble, int index) {
    String bagBegin = bag.substring(0,index);
    String bagEnd = bag.substring(index);
    return bagBegin + marble + bagEnd;
}

Answer 3

You can use StringBuilder.insert​(int offset, String str) to achieve this.

StringBuilder builder = new StringBuilder("MonkeyPony");
for(/* As often as necessary */) {
    int halfway = (int) (builder.length() / 2);
    builder.insert(halfway, "Monkey");
} return builder.toString();