Implementation of Java TreeSet class

Java TreeSet: add() and size() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<String> ts=new TreeSet<>();
        ts.add("Apple");
        ts.add("Orange");
        ts.add("Mango");
        ts.add("Grapes");
        ts.add("Cherry");
        ts.add("Apple");
        
        System.out.println(ts);
        System.out.println("Size: "+ts.size());
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Cherry, Grapes, Mango, Orange]
Size: 5
kodingwindow@kw:~$

Java TreeSet: first() and last() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<String> ts=new TreeSet<>();
        ts.add("Apple");
        ts.add("Orange");
        ts.add("Mango");
        ts.add("Grapes");
        ts.add("Cherry");
        ts.add("Apple");
        System.out.println(ts);
        
        System.out.println(ts.first());
        System.out.println(ts.last());
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Cherry, Grapes, Mango, Orange]
Apple
Orange
kodingwindow@kw:~$

Java TreeSet: higher() and lower() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<String> ts=new TreeSet<>();
        ts.add("Apple");
        ts.add("Orange");
        ts.add("Mango");
        ts.add("Pineapple");
        ts.add("Grapes");
        ts.add("Cherry");
        ts.add("Apple");
        System.out.println(ts);
        
        System.out.println(ts.higher("Orange"));
        System.out.println(ts.lower("Orange"));
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Cherry, Grapes, Mango, Orange, Pineapple]
Pineapple
Mango
kodingwindow@kw:~$

Java TreeSet: headSet(), subSet() and tailSet() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<String> ts=new TreeSet<>();
        ts.add("Apple");
        ts.add("Orange");
        ts.add("Mango");
        ts.add("Pineapple");
        ts.add("Grapes");
        ts.add("Cherry");
        ts.add("Apple");
        System.out.println(ts);
        
        System.out.println(ts.headSet("Grapes"));
        System.out.println(ts.subSet("Apple", "Mango"));
        System.out.println(ts.tailSet("Grapes"));
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Cherry, Grapes, Mango, Orange, Pineapple]
[Apple, Cherry]
[Apple, Cherry, Grapes]
[Grapes, Mango, Orange, Pineapple]
kodingwindow@kw:~$

Java TreeSet: ceiling() and floor() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<Float> ts=new TreeSet<>();
        ts.add(2455.336F);
        ts.add(36985.336F);
        ts.add(1256.39F);
        ts.add(987442.933F);
        ts.add(45.73F);
        ts.add(47.99F);
        ts.add(1.20220F);
        ts.add(12255.00F);
        System.out.println(ts);
        
        System.out.println(ts.ceiling(2500F)); 
        //return least element from the set which is greater than or equal to the given element
        
        System.out.println(ts.floor(100F)); 
        //return greatest element from the set which is less than the given element
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[1.2022, 45.73, 47.99, 1256.39, 2455.336, 12255.0, 36985.336, 987442.94]
12255.0
47.99
kodingwindow@kw:~$

Java TreeSet: ceiling() and floor() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<String> ts=new TreeSet<>();
        ts.add("Apple");
        ts.add("Orange");
        ts.add("Blueberry");
        ts.add("Mango");
        ts.add("Grapes");
        ts.add("Apple");
        ts.add("Bananas");
        
        System.out.println(ts);
        System.out.println(ts.ceiling("Dates"));
        System.out.println(ts.floor("Cherry"));
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Bananas, Blueberry, Grapes, Mango, Orange]
Grapes
Blueberry
kodingwindow@kw:~$

Java TreeSet: pollFirst() and pollLast() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<String> ts=new TreeSet<>();
        ts.add("Apple");
        ts.add("Orange");
        ts.add("Blueberry");
        ts.add("Mango");
        ts.add("Pineapple");
        ts.add("Grapes");
        ts.add("Apple");
        ts.add("Bananas");
        System.out.println(ts);
        
        ts.pollFirst();
        ts.pollLast();
        System.out.println(ts);
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Bananas, Blueberry, Grapes, Mango, Orange, Pineapple]
[Bananas, Blueberry, Grapes, Mango, Orange]
kodingwindow@kw:~$

Java TreeSet: addAll() and containsAll() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<String> ts1=new TreeSet<>();
        ts1.add("Apple");
        ts1.add("Orange");
        ts1.add("Mango");
        ts1.add("Blueberry");
        System.out.println(ts1);
        
        TreeSet<String> ts2=new TreeSet<>();
        ts2.add("Apple");
        ts2.add("Orange");
        ts2.add("Mango");
        ts2.add("Pineapple");
        
        ts1.addAll(ts2);
        System.out.println(ts1);
        System.out.println(ts1.contains("Pineapple"));
        System.out.println(ts2.containsAll(ts1));
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Apple, Blueberry, Mango, Orange]
[Apple, Blueberry, Mango, Orange, Pineapple]
true
false
kodingwindow@kw:~$

Java TreeSet: remove() and removeAll() methods

KW.java

import java.util.TreeSet;

class KW 
{
    public static void main(String[] args) 
    {
        //TreeSet class implements the NavigableSet -> SortedSet -> Set interface
        TreeSet<String> ts=new TreeSet<>();
        ts.add("Apple");
        ts.add("Orange");
        ts.add("Mango");
        ts.add("Grapes");
        ts.add("Cherry");
        ts.add("Apple");
        
        ts.remove("Apple");
        System.out.println(ts);
        
        ts.removeAll(ts); //ts.clear();
        System.out.println("Size: "+ts.size());
        System.out.println(ts.isEmpty());
    }
}

Output

kodingwindow@kw:~$ javac KW.java
kodingwindow@kw:~$ java KW
[Cherry, Grapes, Mango, Orange]
Size: 0
true
kodingwindow@kw:~$

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