Question

How to join an array into a string in Java

Answer 1

import java.util.Arrays;
import java.util.stream.Stream;
import java.util.stream.Collectors;
 
public class MyClass {
    public static void main(String args[]) {

        String[] arr = new String[] { "java", "c", "c++", "rust" };
        
        String result = Arrays.stream(arr).collect(Collectors.joining(", "));

        System.out.println(result);
    }
}
 
 
 
 
/*
run:
 
java, c, c++, rust
 
*/

 

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Answer 2

public class MyClass {
    public static void main(String args[]) {
 
        String[] arr = new String[] { "java", "c", "c++", "rust" };
         
        String result = String.join(", ", arr);  
 
        System.out.println(result);
    }
}
  
  
  
  
/*
run:
  
java, c, c++, rust
  
*/

 

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Answer 3

public class MyClass {
    public static String join(String arr[]) {
        StringBuilder sb = new StringBuilder();
    
        for (int i = 0; i < arr.length; i++) {
            sb.append(arr[i]);
            if (i < arr.length - 1) {
                sb.append(", ");
            }
        }

        return sb.toString(); 
    }

    public static void main(String args[]) {
 
        String[] arr = new String[] { "java", "c", "c++", "rust" };
         
        String result = join(arr); 
 
        System.out.println(result);
    }
}
  
  
  
  
/*
run:
  
java, c, c++, rust
  
*/

 

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