How to split String in Java by WhiteSpace or tabs? Example Tutorial

You can split a String by whitespaces or tabs in Java by using the split() method of java.lang.String class. This method accepts a regular expression and you can pass a regex matching with whitespace to split the String where words are separated by spaces. Though this is not as straightforward as it seems, especially if you are not coding in Java regularly. Input String may contain leading and trailing spaces, it may contain multiple white spaces between words and words may also be separated by tabs. Your solution needs to take care of all these conditions if you just wants words and no empty String. In this article, I am going to show you a couple of examples to demonstrate how you can split String in Java by space. By splitting I mean getting individual words as String array or ArrayList of String, whatever you need.

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How to increase heap size of Eclipse - Solving OutOfMemoryError

If you are running lots of Java projects in Eclipse and it's throwing OutOfMemoryError every now and then it's time to increase the heap memory of Eclipse. Since Eclipse is a Java program, you can increase heap size of Eclipse by using JVM memory options -Xms and -Xmx. There are two ways to provide JVM options to eclipse either updating Eclipse shortcut or adding -vmargs on eclipse.ini file. I prefer the second option because it's clean. I'll tell you the exact steps to increase the java heap space in Eclipse but before that some background why I had to increase heap memory of Eclipse. I was getting "an internal error occurred during repository search . java heap space" while using Maven in Eclipse. Eclipse keep throwing java.lang.OutOfMemory:Java Heap Space while updating the index or searching for maven artifacts.

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How to convert java.util.Date to java.time.LocalDate in Java 8 - Example

The easiest way to convert a java.util.Date to java.time.LocalDate is via Instant, which is the equivalent class of java.util.Date in JDK 8. You can first convert util Date to Instant and then create a LocalDateTime object from that instant at your default timezone. Once you have an instant of LocalDateTime, you can easily convert that to LocalDate or LocalTime in Java. If you are not living under the rock in last two years that its 2016 and Java 8 has been around for more than 2 years, 18th March 2014 Java SE 8 GA happened. In the third attempt of designing a robust date and time API, JDK 8 has come up with JSR 318 new Date and Time API and many programmers have already started using it.

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How to Compare Date in SQL Server Query? Finding All Rows Between Two Dates

It's tricky to use dates in SQL server query, especially if you don't have good knowledge of how DateTime type works in SQL server. For example, one of the frequently asked SQL queries on the interview is to "select all rows where the date is 20151007?" How would you do that? Does following SQL Query will work correctly

select * from table where date = '20151007'

It may or may not, it entirely depends on upon data in your table. When you only provide date part of a DateTime variable, it uses '00:00:00.000' for time part.

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How to check if two Rectangle Overlap in Java - Algorithm

Can you write a Java program to check if two rectangles are overlapping with each other or not? is one of the frequently asked coding questions on tech giants like Facebook, Amazon, Microsoft and others. This is also a kind of problem where it's easy to find opposite or negative conditions e.g. when rectangles are not overlapping and then inverting the result to prove that rectangles are colliding with each other. I first heard about this problem from one of my friend who was on Android game development space. He was asked to write an algorithm to find if given rectangles are intersecting or not. He was given the choice to implement the algorithm in any programming language e.g. Java, C, C++ or even pseudo code was fine, so don't worry about language here, it's more about algorithm and logic. He is a genius so he came successful from that interview, impressing the interviewer, talking about efficiency and accuracy of the algorithm as well.

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3 ways to get number of months and year between two dates in Java?

Earlier I have talked about how to calculate a number of days between two dates in Java (see here), and now you will learn how to get the number of months and years between dates. Though it may look easy, it's not that easy to calculate months and years between dates, unless you take care of all kinds of nuisances like Daylight saving time and when daylight change occurs, leap seconds, and an extra day added in a leap year. Unfortunately, JDK doesn't have a standard method like Period.between() method of Java 8 before to solve this problem. So, if you have to calculate the number of months and years between given dates, you have three main options, first, use Calendar class to write your method to find a number of months and year between given dates, second, use Joda-time library and the third option is to upgrade to Java 8.

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5 Best books for OCAJP8 Exam 1Z0-808 - Java8

It's been more than 2 years since Java SE 8 was launched on 17th March 2014 and almost 2 years since we have OCAJP8 live. You might know that in order to become a Java SE 8 certified developer you need to pass two examples, the OCAJP8 (Exam 1Z0-808) and OCPJP8 (Exam 1Z0-809). The first one is called associate level certification and the second one is called professional level certification. When OCAJP8 first comes, there were not enough good books to prepare this exam and many candidates rely heavily on Java 8 books and professional exam simulators like Whizlabs and Enthuware, but if you are going to appear for the OCAJP8 exam now, there are no such problems. In this article, you will find some of the best books to prepare for OCAJP8 exams.

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