Java + Count duplicates from int array without using any Collection or another intermediate Array?

As a part of the Java interview question paper I have got following issue to solve. But I am bit wonder whether how ...

Difference between Java Enumeration and Iterator?

What is the exact difference between these two interfaces? Does Enumeration have benefits over using Iterator? If a...

What causes a java.lang.ArrayIndexOutOfBoundsException and how do I prevent it??

What does ArrayIndexOutOfBoundsException mean and how do I get rid of it? Here is a code sample that triggers the ...

Java Pass Method as Parameter?

I am looking for a way to pass a method by reference. I understand that Java does not pass methods as parameters, ho...

How to create a directory in Java??

How do I create Directory/folder? Once I have tested System.getProperty("user.home"); I have to create a directory...

How can I use ant <exec> to execute commands on linux??

I would like to use ant to exectue a command like below: &lt;exec executable="echo ptc@123 | sudo -S /app/Windchil...

Java ArrayList Index?

int[] alist = new int [3]; alist.add("apple"); alist.add("banana"); alist.add("orange"); Say that I want to use th...

Extracting .jar file with command line?

I am trying to extract the files from a .jar file. How do I do that using command line? I am running Windows 7 ...

Displaying Image in Java?

I want to display an image but don't know what to do. Whether I have to install some library files or simply it can ...

BlueJ Error: “Incompatible types: int cannot be converted java.lang.String” AND “Incompatible types: java.lang.String cannot be converted to int”?

I'm very new to coding and after trying multiple solutions I came up with, I still can't figure out why what I'm doi...

How to use Joda-Time with Maven??

I it seems to be a very stupid question, because Joda-Time is easy to use that there is no explanation about how to ...

When should I use “this” in a class??

I know that this refers to a current object. But I do not know when I really need to use it. For example, will be th...

How to print to the console in Android Studio??

I just downloaded Android Studio for Linux from: http://developer.android.com/sdk/installing/studio.html I'm wonde...