Latest Tutorials| Questions and Answers|Ask Questions?|Site Map



Home Answers Viewqa Java-Beginners Java Comparable Example

Have Programming Question? Ask it here!
 
 
 


Java Developer
Java Comparable Example
3 Answer(s)      2 years and a month ago
Posted in : Java Beginners


I want to know the use of Comparable Interface. Please provide me one example


Advertisement
View Answers

June 22, 2012 at 12:24 PM


Comparable interface is used to define the natural sort order of a class.List of objects that implement this interface can be sorted automatically by sort method of the list interface. This interface has compareTo() method that is used by the sort() method of the list.

Here is an example that compares two ages using Comparable Interface.

import java.util.*;

class Person implements Comparable{
    int age;

    public void setAge(int age){    
        this.age=age;
    }
    public int getAge(){    
        return this.age;    
    }

    public int compareTo(Object ob){
        if(!(ob instanceof Person)){
            throw new ClassCastException("Invalid object");
        }

        int age = ((Person) ob).getAge();

        if(this.getAge() > age)    
            return 1;
        else if ( this.getAge() < age )
            return -1;
        else
            return 0;

    }
 }
 public class ComparableExample{

    public static void main(String args[]){

        Person one = new Person();        
        one.setAge(35);

        Person two = new Person();        
        one.setAge(30);

        if(one.compareTo(two) > 0) {        
            System.out.println("Person one is elder than Person two!");

        } else if(one.compareTo(two) < 0) {        
            System.out.println("Person one is younger than Person two!");        

        } else if(one.compareTo(two) == 0) {        
            System.out.println("Both Persons are same!");        
        }
     }
 }


August 31, 2012 at 12:58 PM


public class Employee implements Comparable<Employee> {

    int empId;
    String eName;

    public Employee(int empId, String eName) {
        super();
        this.empId = empId;
        this.eName = eName;
    }
    @Override
    public String toString() {

        return "ID:"+empId+"NAME:"+eName;   
    }
    @Override


    public int compareTo(Employee e) {

        return  eName.compareTo(e.eName);
    }

}

import java.util.Iterator;
import java.util.TreeSet;

public class EmpMain {

    /**
     * @param args
     */
    public static void main(String[] args) {
        TreeSet<Employee> ts =new TreeSet<Employee>();
        ts.add(new Employee(123,"vijay"));
        ts.add(new Employee(98,"kumar"));
        ts.add(new Employee(100,"abhi"));
        ts.add(new Employee(50,"dhruv"));
        ts.add(new Employee(150,"sasi"));

        for (Iterator iterator = ts.iterator(); iterator.hasNext();) {
            Employee employee = (Employee) iterator.next();
            System.out.println(employee);
        }

    }

}


August 31, 2012 at 12:59 PM


output:

ID:100NAME:abhi ID:50NAME:dhruv ID:98NAME:kumar ID:150NAME:sasi ID:123NAME:vijay



Related Tutorials/Questions & Answers:
Java Comparable Example
Java Comparable Example  I want to know the use of Comparable Interface. Please provide me one example   Comparable interface is used.... Here is an example that compares two ages using Comparable Interface. import
Sorting data in a jsp using a servlet while implementing comparable - JSP-Servlet
at line 14 of the jsp code. I also want it to implement comparable to use
Advertisements
How do I sort by mutiple columns that are in ArrayList using some comparable class
How do I sort by mutiple columns that are in ArrayList using some comparable class  Iam reading a csv file with 20 columns (all string types) in ArrayList after splitting them. I need to find how can I sort muti columns (i.e.
java persistence example
java persistence example  java persistence example
Java Client Application example
Java Client Application example  Java Client Application example
Example of HashSet class in java
Example of HashSet class in java. In this part of tutorial, we... unique. You can not store duplicate value. Java hashset example. How.... Example of Hashset iterator method in java. Example of Hashset size() method
Example of HashMap class in java
Example of HashMap class in java. The HashMap is a class in java collection framwork. It stores values in the form of key/value pair. It is not synchronized
Java FTP Client Example
Java FTP Client Example  How to write Java FTP Client Example code? Thanks   Hi, Here is the example code of simple FTP client in Java which downloads image from server FTP Download file example. Thanks
FTP Java example
FTP Java example  Where is the FTP Java example on your website? I am... examples of FTP at: FTP Programming in Java tutorials with example code. Thaks... functionality in my Java based application. My application is swing based and I have
Java FTP Example
Java FTP Example  Is there any java ftp example and tutorials... and tutorials that teaches you how to user FTP in your Java project. Most commonly used FTP api in java is Apache FTP. Browse all the FTP tutorials at Java FTP
freemarker example - Java Beginners
an example for freemarker. i want to get the values from java and display those values in the page designed using freemarker(how to get the values from java). and please provide an example with code and directory structure. send me ASAP
java program example - Java Beginners
java program example  can we create java program without static and main?can u plzz explain with an example
Example Code - Java Beginners
Example Code  I want simple Scanner Class Example in Java and WrapperClass Example. What is the Purpose of Wrapper Class and Scanner Class . when i compile the Scanner Class Example the error occur : Can not Resolve symbol
java string comparison example
java string comparison example  how to use equals method in String... strings are not same. Description:-Here is an example of comparing two strings using equals() method. In the above example, we have declared two string
Java hashset example.
Java hashset example.     HashSet is a collection. You can not store duplicate value in HashSet. In this java hashset exmple, you will see how to create HashSet in java application and how to store value in Hashset
Comparable Interface
Comparable Interface      ... of the same class is often required. Once instances are comparable, we can sort them in any order. Comparable interface is defined in java.lang
throws example program java
throws example program java  how to use throws exception in java?   The throws keyword is used to indicate that the method raises..." java.lang.ArithmeticException: / by zero Description:- Here is an example of throws clause. We
Java nested class example
Java nested class example  Give me any example of Nested Class.   Nested Class: Class defined within another class is called nested class... class. Example: public class NestedClass{ private String outer = "Outer
Java: Example - String sort
Java: Example - String sort Sorting is a mechanism in which we sort the data in some order. There are so many sorting algorithm are present to sort the string. The example given below is based on Selection Sort. The Selection sort
Java: Example - Words to array
Java: Example - Words to array This example shows how to convert words to an array. We will use StringTokenizer to achieve the this.  ...; Following example code shows how to do this.      
Java HashMap example.
Java HashMap example. The HashMap is a class in java. It stores values in name values pair. You can store null value of key and values.   Here... of map. Code:  HashMapExample .java package net.roseindia.java
Java File Management Example
of file. Read the example Read file in Java for more information on reading...Java File Management Example  Hi, Is there any ready made API in Java for creating and updating data into text file? How a programmer can write code
Java collection Stack example
:- -1 Description:- The above example demonstrates you the Stack class in java...Java collection Stack example  How to use Stack class in java.... Here is an example of Stack class. import java.util.Stack; public class
Java: Example - ColorDisplay
Java: Example - ColorDisplay In this example code we will show you how to make ColorDisplay application using Swing framework. This example shows color set by RGB scrollbars. In the main method of the example code we are doing
Java: Example - Palindrome test
Java: Example - Palindrome test //========================================================= isPalindrome // This method returns 'true' if the parameter // is a palindrome, a word that is spelled the // same both
Java Map Example
Java Map Example  How we can use Map in java collection?   The Map interface maps unique keys to value means it associate value to unique... Description:- The above example demonstrates you the Map interface. Since Map
Inheritance java Example
Inheritance java Example  How can we use inheritance in java program... for bread Description:- The above example demonstrates you the concept... properties of the superclass. In the given example, the class Animal is a superclass
Java: Example - ToUppercase
Java: Example - ToUppercase Level Introductory Structure... 10 11 12 13 14 15 // ToUpperCase.java Example: Converts text... Example"); window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE
example explanation - Java Beginners
example explanation  can i have some explanation regarding the program given as serialization xample....  Hi friend, import java.io..../java
Java Comparator Example
Java Comparator Example  Can you provide me an example of Comparator Interface?   A comparator object is capable of comparing two different... is an example that compares the object of class Person by age. import java.util.
what is the example of wifi in java
what is the example of wifi in java  i want wi fi programs codings
Java: HandyPerson Example
Java: HandyPerson Example 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40
printing example - Java Beginners
printing example  Is it possible to print java controls using print method? My problem is to print a student mark list using java? The mark list should like that of university mark list
pattern java example
pattern java example  how to print this 1 2 6 3 7 10 4 8 11 13 5 9 12 14 15
Java Queue Example
Java Queue Example  how to use queue in java ?   import...(); queue.add("Java"); queue.add("DotNet"); queue.offer("PHP...().queueExample(); } } Output:- remove: Java element: DotNet poll: DotNet peek
Java collection Queue Example
Java collection Queue Example  How can we use Queue in java... LinkedList(); queue.add("Java"); queue.add("DotNet...) { new MainDemo().queueExample(); } } Output:- remove: Java element
Synchronized with example - Java Beginners
Synchronized with example  Hi Friends, I am beginner in java. what i know about synchonized keyword is,If more that one 1 thread tries to access a particular resource we can lock the method using synchronized keyword. Then after
Java ArrayList Example
Java ArrayList Example  How can we use array list in java program ?   import java.util.ArrayList; public class ArrayListExample { public static void main(String [] args){ ArrayList<String> array = new
Need an Example of calendar event in java
Need an Example of calendar event in java  can somebody give me an example of calendar event of java
array example - Java Beginners
i cannot solve this example
java binary file io example
java binary file io example  java binary file io example
Static Method in java with realtime Example
Static Method in java with realtime Example  could you please make me clear with Static Method in java with real-time Example
Core java linked list example
Core java linked list example  What is the real time example for linked list
Java Example Update Method - Java Beginners
Java Example Update Method  I wants simple java example for overriding update method in applet . please give me that example
Java FTP file upload example
Programming in Java tutorials with example code. Thanks...Java FTP file upload example  Where I can find Java FTP file upload example? What is the link of the FTP examples on your website? Thanks  
Java: JPanel - Example
Java: JPanel - Example // Demo Application of use of JPanel for drawing. -- Fred Swartz // Modified from applet version 2001-09-09, 2002-02-07 import java.awt.*; import java.awt.event.*; import javax.swing.*; import
Java BufferedWriter example
and strings. It write text to a character-output stream. Given below example will give you a clear idea : Example : import java.io.*; public class
What is a vector in Java? Explain with example.
What is a vector in Java? Explain with example.  What is a vector in Java? Explain with example.   Hi, The Vector is a collect of Object... related to Vector in Java program
Java Example projects about STRUTS
Java Example projects about STRUTS  Hai... I completed MCA but i have no job in my hands. But i do some small projects about STRUTS. Please send me some example projects about STRUTS.   Please visit the following link
Java: Example - Scribble
Java NotesExample - Scribble 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41
 

 

 

DMCA.com