10 Examples of Joining String in Java - String.join vs StringJoiner

Certainly! Here are 10 examples of joining strings in Java using String.join and StringJoiner: 

 Example 1: Joining strings with a delimiter using String.join:

String[] words = {"Hello", "world", "Java"};
String joinedString = String.join(" ", words);
System.out.println(joinedString);
// Output: Hello world Java

Example 2: Joining strings with a delimiter using StringJoiner:

StringJoiner joiner = new StringJoiner(", ");
joiner.add("Apple");
joiner.add("Banana");
joiner.add("Orange");
String joinedString = joiner.toString();
System.out.println(joinedString);
// Output: Apple, Banana, Orange

Example 3: Joining strings with a delimiter and prefix/suffix using StringJoiner:

StringJoiner joiner = new StringJoiner(", ", "[", "]");
joiner.add("Red");
joiner.add("Green");
joiner.add("Blue");
String joinedString = joiner.toString();
System.out.println(joinedString);
// Output: [Red, Green, Blue]

Example 4: Joining strings with an empty delimiter using String.join:

String[] words = {"Hello", "world", "Java"};
String joinedString = String.join("", words);
System.out.println(joinedString);
// Output: HelloworldJava

Example 5: Joining strings with no delimiter using String.join:

String[] words = {"Hello", "world", "Java"};
String joinedString = String.join("", words);
System.out.println(joinedString);
// Output: HelloworldJava

Example 6: Joining strings with a delimiter and handling null values using StringJoiner:

StringJoiner joiner = new StringJoiner(", ");
joiner.add("Apple");
joiner.add(null);
joiner.add("Orange");
String joinedString = joiner.toString();
System.out.println(joinedString);
// Output: Apple, Orange

Example 7: Joining strings with a delimiter and skipping null values using StringJoiner:

StringJoiner joiner = new StringJoiner(", ");
joiner.add("Apple");
joiner.add(null);
joiner.add("Orange");
joiner.setEmptyValue("No fruits"); // Set default value when no elements present
String joinedString = joiner.toString();
System.out.println(joinedString);
// Output: Apple, Orange

Example 8: Joining strings with a delimiter and handling empty strings using StringJoiner:

StringJoiner joiner = new StringJoiner(", ");
joiner.add("Apple");
joiner.add("");
joiner.add("Orange");
String joinedString = joiner.toString();
System.out.println(joinedString);
// Output: Apple, , Orange

Example 9: Joining strings with a delimiter and handling empty strings using String.join:

String[] words = {"Apple", "", "Orange"};
String joinedString = String.join(", ", words);
System.out.println(joinedString);
// Output: Apple, , Orange

Example 10: Joining strings with a delimiter and handling empty/null arrays using String.join:

String[] emptyArray = {};
String joinedEmpty = String.join(", ", emptyArray);
System.out.println(joinedEmpty);
// Output: (no output)

String[] nullArray = null;
String joinedNull = String.join(", ", nullArray);
System.out.println(joinedNull);
// Output: (no output)