The merge(StringJoiner other) of StringJoiner adds the contents of the given StringJoiner without prefix and suffix as the next element if it is non-empty. If the given StringJoiner is empty, the call has no effect.
Syntax:
public StringJoiner merge(StringJoiner other)
Parameters: This method accepts a mandatory parameter other which is the StringJoiner whose contents should be merged into this one
Returns: This method returns this StringJoiner
Exception: This method throws NullPointerException if the other StringJoiner is null
Below programs illustrate the merge() method:
Example 1: To demonstrate merge() with delimiter ” “
Java
// Java program to demonstrate// merge() method of StringJoinerimport java.util.StringJoiner;public class GFG { public static void main(String[] args) { // Creating StringJoiner with delimiter " " StringJoiner str1 = new StringJoiner(" "); // Adding elements in the StringJoiner str1.add("Geeks"); str1.add("for"); str1.add("Geeks"); // Print the StringJoiner System.out.println("StringJoiner 1: " + str1.toString()); // Creating the second StringJoiner StringJoiner str2 = new StringJoiner(" "); str2.add("A"); str2.add("Computer"); str2.add("Portal"); // Print the second StringJoiner System.out.println("StringJoiner 2: " + str2.toString()); // Merging the StringJoiner using merge() StringJoiner str = str1.merge(str2); // Printing the merged StringJoiner System.out.println("Merged StringJoiner : " + str); }} |
Output:
StringJoiner 1: Geeks for Geeks StringJoiner 2: A Computer Portal Merged StringJoiner : Geeks for Geeks A Computer Portal
Example 2: To demonstrate merge() with delimiter “, “
Java
// Java program to demonstrate// merge() method of StringJoinerimport java.util.StringJoiner;public class GFG1 { public static void main(String[] args) { // Creating StringJoiner with delimiter ", " StringJoiner str1 = new StringJoiner(", "); // Adding elements in the StringJoiner str1.add("Geeks"); str1.add("for"); str1.add("Geeks"); // Print the StringJoiner System.out.println("StringJoiner 1: " + str1.toString()); // Creating the second StringJoiner StringJoiner str2 = new StringJoiner(", "); str2.add("A"); str2.add("Computer"); str2.add("Portal"); // Print the StringJoiner System.out.println("StringJoiner 2: " + str2.toString()); // Merging the StringJoiner using merge() StringJoiner str = str1.merge(str2); // Printing the merged StringJoiner System.out.println("Merged StringJoiner : " + str); }} |
Output:
StringJoiner 1: Geeks, for, Geeks StringJoiner 2: A, Computer, Portal Merged StringJoiner : Geeks, for, Geeks, A, Computer, Portal
Example 3: To demonstrate NullPointerException
Java
// Java program to demonstrate// merge() method of StringJoinerimport java.util.StringJoiner;public class GFG1 { public static void main(String[] args) { // Creating StringJoiner with delimiter ", " StringJoiner str1 = new StringJoiner(", "); // Adding elements in the StringJoiner str1.add("Geeks"); str1.add("for"); str1.add("Geeks"); // Print the StringJoiner System.out.println("StringJoiner 1: " + str1.toString()); // Creating the second StringJoiner // to be merged as null StringJoiner str2 = null; // Print the StringJoiner System.out.println("StringJoiner 2: " + str2); try { // Merging the StringJoiner using merge() StringJoiner str = str1.merge(str2); } catch (Exception e) { System.out.println("Exception during merge: " + e); } }} |
Output:
StringJoiner 1: Geeks, for, Geeks StringJoiner 2: null Exception during merge: java.lang.NullPointerException
