Scala | Format and Formatted Method

In Scala, string formatting can be accomplished using the format method and the f interpolator. Additionally, the formatted method can be used for simpler formatting tasks. Let's look at each of these methods.

format method:

The format method is similar to Java's String.format method. It uses format specifiers defined by java.util.Formatter.

val formattedString = String.format("Hello %s, you have %d messages.", "Alice", 5)
println(formattedString) // Outputs: Hello Alice, you have 5 messages.

f interpolator:
This is a more Scala-like way to format strings using string interpolation. By prefixing a string with f, you can embed expressions inside ${...} and provide format specifiers.
```
val name = "Bob"
val age = 30
println(f"$name%s is $age%d years old.")  // Outputs: Bob is 30 years old.
```
In the example above, %s is used to format a String and %d is used to format an integer.
formatted method:
The formatted method provides a way to format a single value. It's useful for quick formatting tasks.
```
val price = 12.456
println(price.formatted("%.2f"))  // Outputs: 12.46
```
In the example, %.2f formats the floating-point number to two decimal places.

Example combining them:

Let's combine the knowledge:

val name = "Charlie"
val age = 25
val height = 1.85

val sentence = f"$name%s, aged $age%d, is $height%.2f meters tall."
println(sentence)  // Outputs: Charlie, aged 25, is 1.85 meters tall.

In summary, Scala provides multiple methods to format strings. While the f interpolator offers a concise and idiomatic way to handle string formatting in Scala, the format and formatted methods can be useful in specific situations.

Using format and formatted in Scala:
The format method is used to create formatted strings, and formatted is an alternative syntax.
```
val name = "John"
val age = 30
val formattedString = "%s is %d years old".format(name, age)
```
String Interpolation with formatted in Scala:
String interpolation can be combined with formatted for cleaner syntax.
```
val name = "Alice"
val age = 25
val formattedString = s"$name is $age years old".formatted()
```
Formatting Numeric Values in Scala:
Use format specifiers to control the format of numeric values.
```
val pi = Math.PI
val formattedPi = "Pi value: %.2f".format(pi)
```
Custom Formatting with formatted Method in Scala:
Customize formatting using the formatted method with placeholders.
```
val product = "Laptop"
val price = 1200
val formattedString = "%s: $%d".formatted(product, price)
```
Advanced Formatting Options in Scala Strings:
Explore advanced formatting options such as alignment and width.
```
val alignExample = "%-10s|%10s".format("Left", "Right")
val widthExample = "%20s".format("Wide text")
```

Formatting Dates and Times in Scala:

Format dates and times using java.text.SimpleDateFormat or java.time.format.DateTimeFormatter.

import java.text.SimpleDateFormat
import java.util.Date

val currentDate = new Date()
val formattedDate = new SimpleDateFormat("dd-MM-yyyy").format(currentDate)

String Formatting and Pattern Matching in Scala:

Use pattern matching to extract and format values from strings.

val input = "John,30"
val formatted = input match {
  case s"$name,$age" => s"$name is $age years old"
  case _ => "Invalid format"
}

Comparing Formatted and printf in Scala:
The printf method provides a similar way to format strings.
```
val name = "Sam"
val age = 28
printf("%s is %d years old\n", name, age)
```