Many scenarios come in day to day Java programming when we need to convert a Double value to String or vice versa. In my earlier article we have seen how to convert String to Integer and in this article, we will first see how to convert double to String and the later opposite of that from String to double. One important thing to note is Autoboxing which automatically converts primitive type to Object type and only available from Java 5 onwards. This conversion example assumes the code is running above Java 5 version and actually tested in JDK 1.6, which makes it unable to pass Double object when the method is expecting double primitive value likeString.valueOf(double d) which expect a double value.
Tuesday, October 31, 2017
Monday, October 30, 2017
How to Stop Thread in Java Code Example
The thread is one of the important Classes in Java and multithreading is the most widely used feature, but there is no clear way to stop Thread in Java. Earlier there was a stop method exists in Thread Class but Java deprecated that method citing some safety reason. By default, a Thread stops when the execution of run() method finishes either normally or due to any Exception. In this article, we will How to Stop Thread in Java by using a boolean State variable or flag.
Location:
United States
Sunday, October 29, 2017
What is static import in Java 5 with Example
Static import in Java allows to import static members of the class and use
them, as they are declared in the same class. Static import is introduced in
Java 5 along with other features like Generics,
Enum,
Autoboxing
and Unboxing and variable
argument methods. Many programmers think that using static import can reduce
code size and allow you to freely use static field of external class
without prefixing class name on that. For example without static import you will
access static constant MAX_VALUE of Integer class as Integer.MAX_VALUE but by
using static import you can import Integer.MAX_VALUE and refer
it as MAX_VALUE.
Labels:
coding
,
core java
,
java 5 tutorial
,
programming
Location:
United States
Saturday, October 28, 2017
How to use multiple JQuery UI Date Picker or Datepicker in HTML or JSP page
We often need to use multiple JQuery date picker in one HTML or JSP page,
classical example is online flight booking for return trips, where you need to
pick departure date and arrival date from two separate date pickers. While
designing HTML forms either statically or dynamically using JSP, you may want to
associate date picker with multiple input text field, paragraph or any other
HTML elements. By using JQuery UI and some help from CSS ID and class
selector, we can easily use multiple date pickers in one HTML page. All you need
to do is, declare a CSS class says .datepicker and apply
that class to all HTML elements which need date picker, for example, we have
associated date picker with 4 input text fields, which has .datepicker class.
Labels:
HTML and JavaScript
,
JQuery
,
jQuery UI
,
programming
Friday, October 27, 2017
What is difference between java.sql.Time, java.sql.Timestamp and java.sql.Date - JDBC interview Question
Difference between java.sql.Time, java.sql.Timestamp and java.sql.Date is the most common JDBC question appearing on many core Java interviews. As JDBC
provides three classes java.sql.Date, java.sql.Time and java.sql.Timestamp to
represent date and time and you already have java.util.Date which can
represent both date and time, this question poses a lot of confusion among Java
programmer and that’s why this is one of those tricky
Java questions which is tough to answer. It becomes really tough if the differences between them are not understood correctly.
Labels:
core java
,
core java interview question
,
JDBC
,
programming
,
SQL
Location:
United States
Thursday, October 26, 2017
JSTL foreach tag example in JSP - looping ArrayList
JSTL foreach loop in
JSP
JSTL foreach tag is pretty useful
while writing Java free JSP code. JSTL
foreach tag allows you to iterate or loop
Array List, HashSet
or any other collection without using Java code. After the introduction of JSTL and
expression language(EL) it is possible to write dynamic JSP code without using
scriptlet which clutters jsp pages. JSTL
foreach tag is a replacement of for loop and behaves similarly like foreach
loop of Java 5 but still has some elements and attribute which makes it hard
for first-timers to grasp it. JSTL foreach loop can iterate over arrays,
collections like List,
Set
and print values just like for loop.
Labels:
JSP
,
jsp-servlet
,
JSTL
Location:
United States
How to replace NULL with Empty String in SQL Server? ISNULL() vs COALESCE() Examples
We often need to replace NULL values with empty String or blank in SQL e.g. while concatenating String. In SQL Server, when you concatenate a NULL String with another non-null String the result is NULL, which means you lose the information you already have. To prevent this, you can replace NULL with empty String while concatenating. There are two ways to replace NULL with blank values in SQL Server, function ISNULL(), and COALESCE(). Both functions replace the value you provide when the argument is NULL like ISNULL(column, '') will return empty String if the column value is NULL.
Labels:
Microsoft SQL Server
,
SQL
,
SQL Interview Questions
Wednesday, October 25, 2017
Eclipse shortcut to System.out.println in Java program - Tips
Eclipse IDE provides quick shortcut keys to print System.out.println statement in Java but unfortunately not every Java programmers are familiar with that. Even programmers with 3 to 4 years of experience sometimes don't know this useful Eclipse shortcut to generate System.out.println messages. This Eclipse tip is to help those guys. Let me ask you one question, How many times you type System.out.println in your Java program? I guess multiple times while doing programming, debugging, and testing small stuff. System.out.println is the most preferred way to print something on console because it doesn’t require setups like configuring Log4J or java.util.Logger .
Labels:
coding
,
core java
,
Eclipse
,
programming
Location:
United States
Java program to calculate area of Triangle - Homework, programming exercise example
Calculate the area of Triangle in Java
Write a Java program to calculate
Area of Triangle, accept input from User, and display output in Console is
one of the frequently asked homework questions. This is not a tough
programming exercise but a good exercise for beginners and anyone who has
started working in Java. For calculating the area of a triangle using formula 1/2(base*height), you need
to use arithmetic operators. By doing this kind of exercise you will understand
how arithmetic operators work in Java, subtle details which affect calculation
like precedence and associativity of the operator, etc.
Labels:
Coding Interview Question
,
core java
,
homework
,
programming
Location:
United States
Monday, October 23, 2017
How to Implement Binary Search Tree in Java? Example
A binary search tree or BST is a popular data structure that is used to keep elements in order. A binary search tree is a binary tree where the value of a left child is less than or equal to the parent node and the value of the right child is greater than or equal to the parent node. Since its a binary tree, it can only have 0, 1, or two children. What makes a binary search tree special is its ability to reduce the time complexity of fundamental operations like add, remove, and search, also known as insert, delete and find. In a BST, all these operations (insert, remove, and find) can be performed in O(log(n)) time.
Sunday, October 22, 2017
Tibco tutorial : Certified Messagging
This is in continuation of my previous tibco tutorial. tibco rv is most widely used middleware in enterprise world heavily used in banking and many global investment bank rely on tibco rv for there high speed messaging requirement. its used by many trading application to receive high speed data e.g. Market data. in reliable mode tibco provide reliable delivery of data but not guaranteed means if sender sends data to receiver via tibco multicast network , tibco tries best to deliver that data to receiver but there is no guarantee, data could be lost if receiver is too busy to receive it , if receiver is not running or receiver is hang. In some cases its possible to recover lost data by sending "Resend Request".
Friday, October 20, 2017
5 ways to add multiple JAR in to Classpath in Java
How to add JAR file to Classpath in Java
Adding JAR into classpath is a common task for Java programmer and different programmer do it on different way. Since Java allows multiple ways to include JAR file in classpath, it becomes important to know pros and cons of each approach and How exactly they work. There are 5 ways to add jars on into classpath in Java some of them we have already seen in How classpath works in Java and How to set Path in Java. In this post we will revisit some of those techniques and explore Java 1.6 wildcard to add multiple JAR into classpath. By the way here is 5 ways to add JAR file into classpath. In short knowledge of Path, Classpath and Classloaders are must for any Java programmer, not only from knowledge point of view but also to successfully debug and resolve issues related to Classpath e.g. NoClassDefFoundError and java.lang.ClassNotFoundException in Java.
Labels:
coding
,
core java
,
programming
Location:
United States
What is Iterator and ListIterator in Java Program with Example - Tutorial Code Sample
Iterator in Java is nothing but a traversing object, made specifically for Collection objects like List and Set. we have already aware about different kind of traversing methods like for-loop ,while loop,do-while,for each lop etc,they all are index based traversing but as we know Java is purely object oriented language there is always possible ways of doing things using objects so Iterator is a way to traverse as well as access the data from the collection. Even with traversing with object we have Enumeration, Iterator and ListIterator in Java which we will in this Java Iterator tutorial.
Labels:
core java
,
java collection tutorial
Location:
United States
Thursday, October 19, 2017
Regular Expression in Java to check numbers in String - Example
Regular Expression
to check numeric String
In order to build a regular expression to check if String is number or
not or if String contains any non-digit
character or not you need to learn about character set in Java regular
expression, Which we are going to see in this Java regular expression example.
No doubt Regular Expression is a great
tool in developer arsenal and familiarity or some expertise with regular
expression can help you a lot. Java supports regular expression using java.util.regex.Pattern and java.util.regex.Matchter class, you
can see a dedicated package java.util.regex for a regular expression in Java. Java supports regex from JDK 1.4, which means well before
Generics, Enum, or Autoboxing.
Location:
United States
Difference between private, protected, public and package modifier or keyword in Java
private vs public vs protected vs package in Java
Java has four access modifier namely private, protected and public. package level access is default access level provided by Java if no access modifier is specified. These access modifiers are used to restrict accessibility of a class, method or variable on which it applies. We will start from private access modifier which is most restrictive access modifier and then go towards public which is least restrictive access modifier, along the way we will see some best practices while using access modifier in Java and some examples of using private and protected keywords.
Labels:
core java
,
core java interview question
Location:
United States
Difference between Truncate and Delete command in SQL - Interview Questions with Example
Truncate and delete in SQL are two commands which are used to remove or delete data from a table. Though quite basic in nature both SQL commands can create a lot of trouble until you are familiar with details before using it. The difference between Truncate and delete are not just important to understand perspective but also a very popular SQL interview topic which in my opinion a definite worthy topic. What makes them tricky is the amount of data. Since most Electronic trading system stores, large amounts of transactional data, and some even maintain historical data, a good understanding of delete and the truncate command is required to effectively work in that environment.
Labels:
database
,
database interview questions
,
mysql
,
SQL
Location:
United States
Monday, October 16, 2017
10 Garbage Collection Interview Questions and Answers in Java Programming
GC Interview Questions Answer in Java
Garbage collection interview questions are very popular in both core Java and advanced Java Interviews. Apart from Java Collection and Thread many tricky Java questions stem Garbage collections which are tough to answer. In this Java Interview article, I will share some questions from GC which is asked in various core Java interviews. These questions are based upon the concept of How Garbage collection works, Different kinds of Garbage collectors, and JVM parameters used for garbage collection monitoring and tuning. As I said GC is an important part of any Java interview so make sure you have good command in GC. One more thing which is getting very important is the ability to comprehend and understand Garbage collection Output, more and more interviewer are checking whether the candidate can understand GC output or not.
Labels:
core java
,
core java interview question
,
garbage collection
,
JVM Internals
Location:
United States
Sunday, October 15, 2017
How to convert decimal to binary, octal and hex String in Java Program
This article is a simple Java program that converts the decimal number to binary, octal, and hexadecimal format. When it first came into my mind I thought I would probably need to write whole code to convert decimal to various other radix or base numbers but when I looked Integer class and saw these two ways of converting decimal to binary etc I was simply amazed. It’s indeed extremely easy to do this in java and you can also write this program or use it is.
FIX Log Viewer - Tool to view FIX messages in Readable format
It's been a long time, I wrote anything related to FIX protocol, my last article was about FIX protocol dictionaries, also known as Fixionnary, one of the most important tools of the trade for Java developers and support personnel working in FIX. Today, I am going to share another useful tool called FIX Log Viewer, which allows you to view FIX engine logs in a much more readable format.
Saturday, October 14, 2017
10 Example Queries of SQL Select Command
The Select command in SQL is one of the most powerful and heavily used commands. This is I guess the first command anyone learns in SQL even before CREATE which is used to create a table in SQL. SELECT is used in SQL to fetch records from database tables and you can do a lot many things using Select. For example, you can select all records, you can select few records based on the condition specified in WHERE clause, select all columns using the wild card (*) or only selecting a few columns by explicitly declaring them in a query.
Location:
United States
How to Use Locks in Multi-threaded Java Program
Many Java programmers confused themselves like hell while writing multi-threaded Java programs like where to synchronized? Which Lock to use? What Lock to use etc. I often receive a request to explain how to use Locks in Java, so I thought to write a simple Java program, which is multi-threaded and uses a rather new Lock interface. Remember Lock is your tool to guard shared resources which can be anything e.g. database, File system, a Prime number Generator, or a Message processor. Before using Locks in Java program, it’s also better to learn some basics. Lock is an interface from java.util.concurrent package. It was introduced in JDK 1.5 release as an alternative of the synchronized keyword.
Labels:
coding
,
core java
,
Java multithreading Tutorials
,
programming
,
thread interview questions
Friday, October 13, 2017
Java Program to get input from User from Console or command line- Example Tutorial Code
How to get input from user in Java from command line or console is one of the common thing
,every one started learning Java looks for. It’s second most popular way of
starting programming after HelloWorld
in Java. There are so many ways to get input from User in Java including
command line and Graphical user interface. For beginner simpler the example,
better it is. first and foremost way of getting input from user is String[]
passed to main
method in Java but that only work for one time requirement and its not
interactive. Another way of getting input from User is involving IO classes
like InputStream
to read from console or command line which can be little complicated for true
beginner.
Labels:
Coding Interview Question
,
core java
,
homework
,
programming
Location:
United States
Thursday, October 12, 2017
What is Double Brace Initialization in Java? Anti Pattern Example
Double brace initialization is a Java idiom to initialize a Collection like a list, set and map at the time of declaration. At times, you need a list of fixed elements e.g. supported products, supported currencies or some other config, and on the spot initialization reduces line of code and improves readability. Double brace initialization idiom becomes popular because there is no standard way to create and initialize Collection at the same time in Java. Unfortunately, unlike another language, Java doesn't support collection literals yet. Due to this limitation, creating an unmodifiable List with small numbers of elements requires many lines of code involving creating list, repeatedly calling add() method to add those elements and then finally wrapping it into unmodifiable list as shown below :
Labels:
core java
,
core java interview question
,
design patterns
What is Class in Java Programming with General Example
When I first about Class in Java I just thought what is this Class in Java and from that date to now Whenever we talk about java its really incomplete without classes, every one who are little bit familiar with java knows it’s purely object oriented language means every thing we discuss in java as object .so its very important for learner or anyone who is keen to know about java should know about java class then only they can move forward on java world.
In this article we will see what Java Class, Example of Class in Java is and what makes a Java Class including members, field and method.
Labels:
core java
,
object oriented programming
Location:
United States
Wednesday, October 11, 2017
Google Dart: New Programming language to replace JavaScript
Google Dart: Structured Web Programming language
Google has launched its much-awaited mysterious DART web programming language. Ahh, another programming language…, why does google launched a new language Google DART? What I read from the web is that Google is trying to replace JavaScript as the main web scripting language. Over the years from Netscape Era JavaScript has evolved, formed a large based of Developers and has existing codes, framework, and utilities, so I am not sure how far Google DART can go but this is a serious attempt to replace JavaScript much in the line of Chrome which was launched to replace Internet Explorer and What we see now is they are living happily with their own market share though Chrome is growing and snatching market share from other browsers.
Tuesday, October 10, 2017
Effective Java, 3rd Edition Now Available - Covers JDK 7, 8, and 9 -Must Read Book for Java Programmers in 2019
Hello guys, I have an interesting news to share with you today. After a long wait of almost 10 years, Effective Java 3rd edition is finally coming this year, hopefully, December 2017. The Effective Java 2nd Edition was released in May 2008 and updated for Java SE 6, but it been, good 10 years now and there is a lot of interest from Java developers around the world for Effective Java 3rd edition after Java SE 8 release and I am very happy to inform you guys that, finally, all our wishes are granted and Effective Java 3rd edition is set to arrive this year. It will not only cover Java 9 release but also all the changes from Java 7 and Java 8.
Monday, October 9, 2017
How to write build.xml and run build in Apache ANT
This is the second article on Apache ANT tutorials for beginners series As I have always said that I like the short , clear and concise tutorial which tells about few concept but in a clear and concise manner and put weight on fundamentals . I try to adopt same theory while writing my blog post while writing my experience coupled with the concept which is important for a software developer point of view.
SQL Server JDBC Error: The TCP/IP connection to the host Failed
I had installed SQL SERVER 2014 Express edition and I was trying to connect to SQL SERVER from Java program using JDBC, but I was repeatedly getting the following error:
com.microsoft.sqlserver.jdbc.SQLServerException: The TCP/IP connection to the host localhost, port 1433 has failed. Error: "connect timed out. Verify the connection properties. Make sure that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port. Make sure that TCP connections to the port are not blocked by a firewall.".Error while closing connection !!null
com.microsoft.sqlserver.jdbc.SQLServerException: The TCP/IP connection to the host localhost, port 1433 has failed. Error: "connect timed out. Verify the connection properties. Make sure that an instance of SQL Server is running on the host and accepting TCP/IP connections at the port. Make sure that TCP connections to the port are not blocked by a firewall.".Error while closing connection !!null
Top 10 JSP Interview Questions Answers for Java Programmer
These JSP interview questions and answers are asked in the various J2EE interview and focus on the view part of the MVC framework. JSP or Java Server Pages is a Java technology used to render a dynamic view. Whenever you go for any Java web developer interview there are always some interview questions on JSP. This article is a collection of some JSP interview questions which has asked in the various interview to my friends and colleagues. You can easily find answers to these JSP interview questions by google but I have included my version for quick reference.
Location:
United States
Right way to Close InputStream and OutputStream in Java
For some unknown reasons many Java programmers are not very comfortable with IO package. I don't know why, but I have found them much more comfortable with java.lang and java.util than java.io. One possible reason of this could be that, writing IO code require a bit of C++ like programming, which involves doing clean-up, releasing resources once done etc. Since Java made coding a lot easier by taking care of memory management, unknowingly it also introduced bad practice of not releasing resource after use e.g. database connections, socket connection, files, directory, printers, scanners or any other scarce resource.
Sunday, October 8, 2017
How SubString method works in Java - Memory Leak Fixed in JDK 1.7
Substring method from String class is one of most used method in Java, and it's also part of an interesting String interview question e.g. How substring works in Java or sometime asked as how does substring creates memory leak in Java. In order to answer these questions, you knowledge of implementation details is required. Recently one of my friend was drilled on substring method in Java during a Java interview, he was using substring() method from long time, and of course all of us has used this, but what surprises him was interviewer's obsession on Java substring, and deep dive till the implementation level.
Labels:
core java
,
core java interview question
,
Java String
Location:
United States
How to build project using Apache ANT ? ANT Build Tutorials for Beginners
Apache Ant tutorials for beginners
Hi Guys, today I would like to share some of my experience while working with ant build tool in form of short ant tutorials, ant is one tool which has gained its place in almost everywhere, it’s integral part of any project’s build system and provide foundation for complex, extensible build environment. I have been using ANT from my early programming days and I have seen some of the best designed build environments around ANT. In these ant tutorials for beginners we will see what is ant build tool? How to use ANT for building project? Fundamentals of ANT build tool, setting up ant build environment etc. I have created a series of ant tutorials and you can check next part of ant tutorials by following links ant tutorial part 2 and ant tutorial part 3.Saturday, October 7, 2017
20 Questions You can ask to Interviewer in Programming Job Interviews?
From the first round to HR round, from telephonic to face-to-face, in almost all kind of programming interviews, there will be a time when Interviewer will give you a chance to ask questions. Many programmers are too concern about asking questions, and they politely decline ; Well it's your chance to learn about the Job you are going to do, and you shouldn't let this opportunity goes away. The interviewer, also judges you by your questions; a good, thoughtful, positive question can create the great impression on Interviewer's mind. It also shows that the interest of a candidate for a Job.
10 Programming Best Practices to Name Variables, Methods, Classes and Packages
What's in a name? "A rose by any other name would smell as sweet" is a famous quote from William Shakespeare's classic Romeo and Juliet, but sorry to say, name matter a lot in programming and coding. It's also said that code is the best document for any software because any other document or comments can become outdated quickly, but code will always tell you the truth. And, If code is the best document than names are the most critical element of it. Every effort, small or big, invested while naming variables or methods, pays in both short term and long term. In fact, if you ask me just one coding practice to follow, It would definitely recommend giving meaningful names to your variables and methods.
Labels:
best of javarevisited
,
best practices
,
coding
,
core java
,
programming
Top 10 Java String interview Question answers - Advanced
10 Java String interviews Question answers
String interview questions in Java is one of Integral part of any Core Java or J2EE interviews. No one can deny the importance of String and how much it is used in any Java application irrespective of whether its core Java desktop application, web application, Enterprise application or Mobile application. The string is one of the fundamental of Java programming language and correct understanding of String class is a must for every Java programmer. What makes String interview questions in Java even more interesting is the special status of String in terms of features and privileges it has, like the + operator is kind of overloaded to perform String concatenation despite the fact that Java does not support operator overloading. There is a separate String pool to store String literal etc.
String interview questions in Java is one of Integral part of any Core Java or J2EE interviews. No one can deny the importance of String and how much it is used in any Java application irrespective of whether its core Java desktop application, web application, Enterprise application or Mobile application. The string is one of the fundamental of Java programming language and correct understanding of String class is a must for every Java programmer. What makes String interview questions in Java even more interesting is the special status of String in terms of features and privileges it has, like the + operator is kind of overloaded to perform String concatenation despite the fact that Java does not support operator overloading. There is a separate String pool to store String literal etc.
Labels:
core java
,
core java interview question
,
Java String
Location:
United States
Friday, October 6, 2017
How to Set Path for Java Unix Linux and Windows
PATH is one of fundamental Environment variable on shell or DOS but it’s commonly associated with Java mainly because if we try to run a java program which doesn't include Java executable in PATH then we say PATH is not set for Java and we need to set the path for Java. I have also seen the developer getting confused over path and classpath in java. Though both path and classpath provide run-time settings for any java environment which is required to compile and executes Java program they are completely different to each other.
What is Inheritance in Java and OOPS Tutorial - Example
Inheritance in Java is an Object oriented or OOPS
concepts, which allows to emulate real world Inheritance behavior, Inheritance
allows code reuse in Object oriented programming language e.g. Java. Along with
Abstraction,
Polymorphism
and Encapsulation,
Inheritance forms basis of Object oriented programming. Inheritance is
implemented using extends keyword in Java and When one
Class extends another Class it inherit all non
private members including fields and methods. Inheritance in Java can be
best understand in terms of Parent and Child class,
also known as Super class and Sub class in Java programming language.
Labels:
core java
,
object oriented programming
,
programming
Location:
United States
Wednesday, October 4, 2017
Improving Performance of java application
This is a big topic to discuss as there are many approaches that involve analyzing the performance of an application starting from profiling application to finding the bottleneck.
here I am putting some of the basic tricks for improving performance which I learned in my early days in java, I will keep posting some approach, experience on performance improvement as and when time allows.
for now, here are naive's tips for making your program run faster.
here I am putting some of the basic tricks for improving performance which I learned in my early days in java, I will keep posting some approach, experience on performance improvement as and when time allows.
for now, here are naive's tips for making your program run faster.
Labels:
core java
,
Java Performance
,
JVM Internals
Location:
United States
Database Website to Run and Practice SQL Query Online for FREE - SQLFiddle
Another day, I was looking for a website to execute SQL query online, since I have uninstalled Microsoft SQL Server because of memory and CPU constraint and I don't want to install it again, just for executing another query. Also, installing database is pain, it takes time and eats up lots of resources e.g. RAM memory, CPU, etc; Given so many databases to work with e.g. Oracle, MySQL, Sybase, PostgreSQL, and SQLLite, it's not really possible to have all of them in your poor laptop. Fortunately, my search leads me to this wonderful site called SQLFiddle, this is what exactly I wanted. This site offers support for a lot of popular databases, allows you to build your database schema online, and execute SQL query on the fly.
Monday, October 2, 2017
How to convert java.util.Date to java.sql.Date - JDBC Example
You often need to convert java.util.Date to java.sql.Date if you are storing dates in database e.g. SQL SERVER or MySQL. Since JDBC has their own data types for date and time e.g. java.sql.Date, java.sql.Time and java.sql.TimeStamp to match with database date, time and date-time types, you cannot pass a java.util.Date directly. All methods which are suppose to store dates e.g. setDate(paramName, paramValue) expects java.sql.Date, so it becomes essential to know how to convert java.util.Date to java.sql.Date in JDBC. You would be surprised to know that java.sql.Date is a subclass of java.util.Date and all it does is suppress or remove time-related fields from java.util.Date.
What is PriorityQueue or priority queue data structure in Java with Example - Tutorial
PriorityQueue is an unbounded Queue implementation in Java, which is based on priority heap. PriorityQueue allows you to keep elements in a particular order, according to there natural order or custom order defined by Comparator interface in Java. Head of priority queue data structure will always contain least element with respect to specified ordering. For example, in this post, we will create a PriorityQueue of Items, which are ordered based upon there price, this will allow us to process Items, starting from lowest price. Priority queue is also very useful in implementing Dijkstra algorithm in Java. You can use to PriorityQueue to keep unsettled nodes for processing.
Labels:
core java
,
java collection tutorial
,
programming
5 Articles to Learn about Shellshock Bash Bug
The year of 2014 is looking like a year of biggest software bug and vulnerabilities. Earlier this year, internet was bleeding by Heartbleed vulnerability and now it's shocked by ShellShock bug. To me it looks like even bigger than Heartbleed, just because it's a bug in Bash Shell, our own bash shell, most popular among all UNIX shells like C and K. Given most of the servers in Investment banks, Insurance companies, Clouds and e-commerce domain are Linux Servers with bash being most used shell, impact is quite large. I am sure people with Microsoft stack is smiling somewhere :), but wait, read the full article. First details of Shellshock bug emerged Wednesday last week, since then it has gone viral, both online and offline.
Sunday, October 1, 2017
How to override hashcode in Java example - Tutorial
Equals and hashcode methods are two primaries but yet one of the most important methods for java developers to be aware of. Java intends to provide equals and hashcode for every class to test equality and to provide a hash or digest based on the content of the class. The importance of hashcode increases when we use the object in different collection classes which works on hashing principle e.g. hashtable and hashmap. A well-written hashcode method can improve performance drastically by distributing objects uniformly and avoiding a collision.
Labels:
core java
,
equals and hashcode
Location:
United States
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