Kotlin Commons Library

Commons library containing reusable functions, extensions, and objects for Kotlin

Compatibility

• Java 21
• Spring Boot 3

Setup

Add Dependency

Gradle

implementation("io.opengood.commons:kotlin-commons:VERSION")

Maven

<dependency>
    <groupId>io.opengood.commons</groupId>
    <artifactId>kotlin-commons</artifactId>
    <version>VERSION</version>
</dependency>

Note: See Release version badge above for latest version.

Features

Annotations

NoArg

• Automatically generate no argument constructor on data class:

  Example:

  import io.opengood.commons.kotlin.annotation.NoArg
  
  @NoArg
  data class Greeting(
      val name: String
  )

  Add configuration to build.gradle.kts:

  noArg {
      annotation("io.opengood.commons.kotlin.annotation.NoArg")
      invokeInitializers = true
  }

---

Extensions

Methods

Array

printAll

• Print all arguments in an array:

  Example:

  import io.opengood.commons.kotlin.extension.method.printAll
  
  arrayOf("foo", "bar").printAll()

---

BigDecimal

roundUp

• Rounds decimal value half up to specified scale:

  Example:

  import io.opengood.commons.kotlin.extension.method.roundUp
  
  BigDecimal(12.346).roundUp(2)

---

List

containsIgnoreCase

• Case-insensitive string contained in list:

  Example:

  import io.opengood.commons.kotlin.extension.method.containsIgnoreCase
  
  listOf("foo", "bar").containsIgnoreCase("foo")

sortAscending

• Sorts list of map keys in ascending order:

  Example:

  import io.opengood.commons.kotlin.extension.method.sortAscending
  
  val list = listOf(
      mapOf(
          "foo" to "bar",
          "baz" to "pas"
      ),
      mapOf(
          "foo" to "par",
          "baz" to "taz"
      )
  )
  
  list.sortAscending("baz")

sortDescending

• Sorts list of map keys in descending order:

  Example:

  import io.opengood.commons.kotlin.extension.method.sortDescending
  
  val list = listOf(
      mapOf(
          "baz" to "pas",
          "foo" to "bar"
      ),
      mapOf(
          "baz" to "taz",
          "foo" to "par"
      )
  )
  
  list.sortDescending("baz")

---

Map

containsMultipleListItems

• Map entry contains more than one value in list:

  Example:

  import io.opengood.commons.kotlin.extension.method.containsMultipleListItems
  
  mapOf("foo" to listOf("bar", "baz")).containsMultipleListItems("foo")

keyByIndex

• Gets map key by index

  Example:

  import io.opengood.commons.kotlin.extension.method.keyByIndex
  
  val map = mapOf("foo" to "bar")
  map.keyByIndex(0)

notContainsKey

• Key not contained in map:

  Example:

  import io.opengood.commons.kotlin.extension.method.notContainsKey
  
  emptyMap<String, String>().notContainsKey("foo")

notContainsValue

• Value not contained in map:

  Example:

  import io.opengood.commons.kotlin.extension.method.notContainsValue
  
  emptyMap<String, String>().notContainsValue("foo")

putIfNotAbsent

• Puts an entry into a map if it does not exist:

  Example:

  import io.opengood.commons.kotlin.extension.method.putIfNotAbsent
  import io.opengood.commons.kotlin.function.makeEntry
  
  val map = mutableMapOf<String, String>()
  val entry = makeEntry("foo", "bar")
  map.putIfNotAbsent(entry)

valueByIndex

• Gets map value by index

  Example:

  import io.opengood.commons.kotlin.extension.method.valueByIndex
  
  val map = mapOf("foo" to "bar")
  map.valueByIndex(0)

---

Pair

toEntry

• Convert Pair to map entry:

  Example:

  import io.opengood.commons.kotlin.extension.method.toEntry
  
  Pair("foo", "bar").toEntry()

---

String

capitalizeWord

• Capitalize word in a string:

  Example:

  import io.opengood.commons.kotlin.extension.method.capitalizeWord
  
  "hello".capitalizeWord()

capitalizeWords

• Capitalize all words in a string:

  Example:

  import io.opengood.commons.kotlin.extension.method.capitalizeWords
  
  "hello world!".capitalizeWords()

containsIgnoreCase

• Case-insensitive substring contained in string:

  Example:

  import io.opengood.commons.kotlin.extension.method.containsIgnoreCase
  
  "Hello World!".containsIgnoreCase("HELLO")

equalsIgnoreCase

• Case-insensitive string equals substring:

  Example:

  import io.opengood.commons.kotlin.extension.method.equalsIgnoreCase
  
  "Hello World!".equalsIgnoreCase("HELLO WORLD!")

isBoolean

• Value indicating if string is boolean:

  Example:

  import io.opengood.commons.kotlin.extension.method.isBoolean
  
  "true".isBoolean()

isInt

• Value indicating if string is integer:

  Example:

  import io.opengood.commons.kotlin.extension.method.isInt
  
  "12345".isInt()

isUuid

• Value indicating if string is UUIS:

  Example:

  import io.opengood.commons.kotlin.extension.method.isUuid
  
  "12102e90-2918-4578-a9a1-bb16ac81d8f8".isUuid()

toIntOrZero

• Value indicating if string is integer, if so then value as integer, and if not, then value is zero:

  Example:

  import io.opengood.commons.kotlin.extension.method.toIntOrZero
  
  "12345".toIntOrZero()

---

Properties

Decimal

Property	Description	Value
zero	BigDecimal zero value	BigDecimal(0)

Example:

import io.opengood.commons.kotlin.extension.property.*

Decimal.zero

---

String

Property	Description	Value
carriageReturn	Carrier return	\r
comma	Comma	,
crlf	Carriage return/line feed	\n\r
empty	Empty string
equalsSign	Equals sign	=
greaterThanSign	Greater than sign	>
lessThanSign	Less than sign	<
newline	Newline	\n
pipe	Pipe	`\
tab	Tab	\t
whitespace	Whitespace

Example:

import io.opengood.commons.kotlin.extension.property.*

String.carriageReturn
String.comma
String.crlf
String.empty
String.equalsSign
String.greaterThanSign
String.lessThanSign
String.newline
String.pipe
String.tab
String.whitespace

---

UUID

Property	Description	Value
empty	Empty UUID	UUID(0L, 0L)

Example:

import io.opengood.commons.kotlin.extension.property.*

Uuid.empty

---

Functions

I/O

captureStdOut

• Captures standard output of specified function:

  Example:

  import io.opengood.commons.kotlin.function.captureStdOut
  
  val output = captureStdOut { print("foo") }

---

Map

makeEntry

• Creates a map entry using specified key and value:

  Example:

  import io.opengood.commons.kotlin.function.makeEntry
  
  makeEntry("foo", "bar")

---

Infix Functions

Boolean

then

• Shorthand ternary function for evaluating simple conditions then returning simple results:

  Example:

  import io.opengood.commons.kotlin.infix.then
  
  val condition = 1
  val result = (condition == 1) then { true } ?: false

---

Generic Type

firstOrDefault

• Gets value of specified object, if not null, otherwise, gets specified default value:

  Example:

  import io.opengood.commons.kotlin.infix.firstOrDefault
  
  "foo" firstOrDefault "bar"

---

Integer

isDivFactorOf

• Gets value indicating if specified integer is divisible by a factor of specified value:

  Example:

  import io.opengood.commons.kotlin.infix.isDivFactorOf
  
  10 isDivFactorOf 5