Week 68 — Which mechanisms does Java provide for concatenating `String`s with other variables?

[thorny anchor]

Question of the Week #68

Which mechanisms does Java provide for concatenating Strings with other variables?

[warped surge]

String concatenation is the mechanism of combining a String with another variable in order to get another String containing both the original String and the other variable.
Java allows doing that using the + operator:

String s = "Hello ";
String t = "World ";
int i = 1337;
String result = s + t + i;
System.out.println(result);//Hello World 1337

Other than that, the String class provides a concat method that can concatenate two Strings:

String s = "Hello ";
String t = "World";
String result = s.concat(t);
System.out.println(result);//Hello World

It is also possible to use String.format which allows printf-like format specifiers:

String s = "Hello";
String t = "World";
int i = 1337;
String result = String.format("%s %s %d", s, t, i);
System.out.println(result);//Hello World 1337

Aside from that, String templates, which are currently (as of Java 22) a Preview feature, allow doing that as well:

String s = "Hello";
String t = "World";
int i = 1337;
String result = STR."\{s} \{t} \{i}";
System.out.println(result);//Hello World 1337

📖 Sample answer from dan1st

[warped surge]

Java provides + operator to concatenate the string with other variables
Like
int a = 3;
String str = "times";
System.out.print(a+str);
// 3times
We can also use stringbuilder for optimised concatenation as strings are immutable in java for larger string we use stringbuilder

Submission from rahulsaini_1957

Usually you can concatenate with String + var1

Submission from ogbudsz

For concatenation of string with other variables addition "+" mechanism is provided by java

Submission from dead_pool4

The use of the ‘+’ operator allows the concatenation of various data types to string types. For example
str = “Hello” and x = 1
str + x = Hello1
Using the StringBuilder class and using .append() has the same effect though StringBuilder has more methods to use

Submission from _draws

For example StringBuilder

Or method .concat for string object

In the worst case "s += i" or s = "s + i"

I'll give code example later if needed

Submission from matieuu

In java we can use an empty string

Eg:

class hi{
void hello{
String a=“hi”
String B=“world”
String c=a+B}}

@thorny anchor

Submission from juanisrockingx

1. We can use '+' operator.

int age = 25;
String message = "Hello, my name is " + name + " and I am " + age + " years old.";
System.out.println(message);```
2. Also String.format() is available.
```String name = "Cutie";
int age = 25;
String message = "Hello, my name is %s, and I am %d years old.";
System.out.println(message);```
3. StringBuilder is another option.
```String name = "Cutie";
int age = 25;
StringBuilder builder = new StringBuilder();
builder.append("Hello, my name is ").append(name).append(" and I am ").append(age).append(" years old.");
String message = builder.toString();
System.out.println(message);```

⭐ Submission from cutie.joy