Example: package com.w3schools;   import java.util.ArrayList; import java.util.HashSet; import java.util.List; import java.util.stream.Collectors;   public class Test { public static void main(String args[]){ ArrayList<String> arrayList = new ArrayList<String>(); arrayList.add("Jai"); arrayList.add("Mahesh"); arrayList.add("Vivek"); arrayList.add("Naren"); arrayList.add("Hemant"); arrayList.add("Vishal"); arrayList.add("Vishal"); arrayList.add("Naren"); System.out.println("Actual ArrayList:"+arrayList); //Prior to Java 8 List<String> newList1 = new ArrayList<>(new HashSet<>(arrayList)); System.out.println("Modified ArrayList:"+newList1); //Using Java 8 List<String> newList2 = … Read more

Example: package com.w3schools;   import java.util.Hashtable; import java.util.Set;   class Employee{ private String name; private int salary; private int id;   public Employee(int id, String name, int salary){ this.id = id; this.name = name; this.salary = salary; }   public String getName() { return name; } public void setName(String name) { this.name = name; } … Read more

Example: package com.w3schools;   import java.util.Hashtable;   class Employee{ private String name; private int salary; private int id;   public Employee(int id, String name, int salary){ this.id = id; this.name = name; this.salary = salary; }   public String getName() { return name; } public void setName(String name) { this.name = name; } public int … Read more

We can use clear() method to remove all elements from hashtable in java. Syntax: hashtable.clear(); Example: package com.w3schools;   import java.util.Hashtable;   public class Test { public static void main(String args[]){ //Create Hashtable object. Hashtable<String, String> hashtable = new Hashtable<String, String>(); //Add objects to the Hashtable. hashtable.put("1", "Jai"); hashtable.put("2", "Mahesh"); hashtable.put("3","Vivek"); System.out.println(hashtable); hashtable.clear(); System.out.println("Content After … Read more

We can use entrySet() method get all key-value pairs from hashtable in java. It returns a Set object with all key-value pairs. Syntax: hashtable.entrySet(); Example: package com.w3schools;   import java.util.Hashtable; import java.util.Map.Entry; import java.util.Set;   public class Test { public static void main(String args[]){ //Create Hashtable object. Hashtable<String, String> hashtable = new Hashtable<String, String>(); //Add … Read more

We can use keySet() method get all keys from hashtable in java. It returns a Set object with all keys. Syntax: hashtable.keySet(); Example: package com.w3schools;   import java.util.Hashtable; import java.util.Set;   public class Test { public static void main(String args[]){ //Create Hashtable object. Hashtable<String, String> hashtable = new Hashtable<String, String>(); //Add objects to the Hashtable. … Read more

We can use containsValue() method to search a value in hashtable. Syntax: hashtable.containsValue(specifiedValue); Example: package com.w3schools;   import java.util.Hashtable;   public class Test { public static void main(String args[]){ //Create Hashtable object. Hashtable<String, String> hashtable = new Hashtable<String, String>(); //Add objects to the Hashtable. hashtable.put("1", "Jai"); hashtable.put("2", "Mahesh"); hashtable.put("3","Vivek"); System.out.println(hashtable); if(hashtable.containsValue("Vivek")){ System.out.println("The Hashtable contains value … Read more

We can use containsKey() method to search a key in hashtable. Syntax: hashtable.containsKey(specifiedKey); Example: package com.w3schools;   import java.util.Hashtable;   public class Test { public static void main(String args[]){ //Create Hashtable object. Hashtable<String, String> hashtable = new Hashtable<String, String>(); //Add objects to the Hashtable. hashtable.put("1", "Jai"); hashtable.put("2", "Mahesh"); hashtable.put("3","Vivek"); System.out.println(hashtable); if(hashtable.containsKey("2")){ System.out.println("The Hashtable contains key … Read more

We can use putAll() method to copy map content to another hashtable in java. Syntax: hashtable.putAll(hashMap); Example: package com.w3schools;   import java.util.HashMap; import java.util.Hashtable;   public class Test { public static void main(String args[]){ //Create Hashtable object. Hashtable<String, String> hashtable = new Hashtable<String, String>(); //Add objects to the Hashtable. hashtable.put("1", "Jai"); hashtable.put("2", "Mahesh"); hashtable.put("3","Vivek"); System.out.println(hashtable); … Read more

To iterate through hashtable in java, first we have to get all keys as set object and then fetch each element using key. Example: package com.w3schools;   import java.util.Hashtable; import java.util.Set;   public class Test { public static void main(String args[]){ //Create Hashtable object. Hashtable<String, String> hashtable = new Hashtable<String, String>(); //Add objects to the … Read more