Since Java 9, we can use aList<E>.of(E… elements)static factory method to create an immutable list: @Test(expected = UnsupportedOperationException.class)publicfinalvoidgivenUsingTheJava9_whenUnmodifiableListIsCreated_thenNotModifiable(){finalList<String> list =newArrayList<>(Arrays.asList("one...
By doing so, we are hiding the original tokens list so no one can even get a reference of it and change it. final class Record { private final long id; private final String name; private final List<String> tokens; public Record(long id, String name, List<String> tokens) { this.id ...
package com.howtodoinjava; import java.util.List; public class ImmutableCollections { public static void main(String[] args) { List<String> names = List.of("Lokesh", "Amit", "John"); //Preserve the elements order System.out.println(names); //names.add("Brian"); //UnsupportedOperatio...
importcom.google.common.collect.ImmutableList; classMain { publicstaticvoidmain(String[]args) { // create an immutable list containing the given elements, in order ImmutableList<String>immutableList=ImmutableList.of("C","C++","Java");
arpit.java2blog.bean; import java.util.ArrayList; public final class Country { // declared private final instance variable private final String countryName; // Mutable object private final ArrayList listOfStates; public Country(String countryName, ArrayList listOfStates) { super(); this.country...
// Create an immutable list of strings ImmutableList<string> colors = ImmutableList.Create("Red", "Green", "Blue"); // Iterate over all items in the list and print them foreach (string s in colors) { Console.WriteLine(s); } /* Example output: Red Green Blue */ Cet...
Java 中的变量在不同数据类型的转换分为两种:隐式转换、显式(强制)转换。比如下面就是几个简单直观的例子: inta=2;// a = 2 doublea=2;// a = 2.0 (Implict) inta=(int)18.7// a = 18 doublea=(double)2/3;// a = 0.6666... inta=18.7;// ERROR ...
The second assertEquals will fail because adding an element to the list changes its size, therefore, it isn’t an immutable object. 4. Immutability in Java Now that we know how to avoid changes to the content of a variable, we can use it to build the API of immutable objects. Buildin...
Immutable中的Collection是一个基类,放在后端语言Java中来说就是一个抽象类,其中定义了很多方法,提供给子类来实现。因此Collection不能直接使用其构造函数。其中它又分成了几个子类,分别是Collection.Keyed,Collection.Indexed, orCollection.Set,List/Map/Set/Stack分别都是继承他们而来。
IImmutableList<T> IImmutableQueue<T> IImmutableSet<T> IImmutableStack<T> ImmutableArray ImmutableArray<T>. Constructor ImmutableArray<T>. Enumerador ImmutableArray<T> InmutableDictionary ImmutableDictionary<TKey,TValue>. Constructor ImmutableDictionary<TKey,TValue>. Enumerador ImmutableDictionary<TKey...