Trending questions in Java

–1 vote
1 answer

What is the difference between oracle JDK and open JDK

Both OpenJDK and Oracle JDK are created ...READ MORE

Jul 10, 2018 in Java by Akrati
• 3,190 points
1,106 views
0 votes
1 answer

Iterating through a Collection, avoiding ConcurrentModificationException when removing in loop

You can either use the iterator directly ...READ MORE

Jul 3, 2018 in Java by Rishabh
• 3,620 points
1,340 views
0 votes
2 answers

Generate an alpha-numeric string randomly

Java supplies a way of doing this ...READ MORE

Jul 18, 2018 in Java by Daisy
• 8,140 points
2,619 views
0 votes
1 answer

How can we convert Strings to and from UTF8 byte arrays?

To convert STring to byte[]: String s = ...READ MORE

Jun 21, 2018 in Java by Akrati
• 3,190 points
1,848 views
0 votes
1 answer

Convert comma-separated String to ArrayList?

List<String> alist = Arrays.asList(str.split("\\s*,\\s*")); The above code splits ...READ MORE

May 17, 2018 in Java by sharth
• 3,370 points
3,349 views
0 votes
1 answer

What are the practical uses for AtomicInteger?

There are two main uses of AtomicInteger: As an ...READ MORE

Jul 18, 2018 in Java by Akrati
• 960 points
630 views
0 votes
1 answer

How can we format float to n decimal places ?

You may pass the float value: String.format("%.2f", floatVal); READ MORE

Jul 2, 2018 in Java by sophia
• 1,400 points
1,329 views
0 votes
2 answers

How to sort array in descending order

there are some traditional ways that you ...READ MORE

Jul 4, 2018 in Java by Priyaj
• 58,020 points
1,187 views
0 votes
1 answer

Bean Scopes in Java Spring

According to my knowledge, the Spring Framework ...READ MORE

Jul 4, 2018 in Java by geek.erkami
• 2,680 points
1,191 views
0 votes
1 answer

What is the native keyword in Java?

The native keyword is applied to a method to ...READ MORE

Jul 16, 2018 in Java by scarlett
• 1,290 points
643 views
0 votes
1 answer

Injecting property value into Spring Bean using annotations

I think you can easily perform this ...READ MORE

May 29, 2018 in Java by code.reaper12
• 3,500 points
2,706 views
0 votes
2 answers

When and how to use Super() keyword in Java?

super() is used to call immediate parent. super() can be ...READ MORE

Jul 9, 2018 in Java by Sushmita
• 6,920 points
1,870 views
0 votes
1 answer

Programmatically closing a JFrame

If you want the GUI to behave ...READ MORE

Jun 21, 2018 in Java by Parth
• 4,640 points
1,679 views
0 votes
1 answer

Annotation wiring in Spring

By default, Annotation wiring is not turned ...READ MORE

Jul 4, 2018 in Java by code.reaper12
• 3,500 points
1,146 views
0 votes
2 answers

Is there a destructor in Java?

try (BufferedReader br = new BufferedReader(new FileReader(path))) ...READ MORE

Sep 4, 2018 in Java by Sushmita
• 6,920 points
938 views
0 votes
1 answer

How to perform Java 256 bit AES Password Based Encryption?

/* Derive the key, given password and ...READ MORE

Jun 21, 2018 in Java by Akrati
• 3,190 points
1,657 views
0 votes
1 answer

What is the equivalent of the C++ Pair<L,R> in Java?

In a thread on comp.lang.java.help, Hunter Gratzner ...READ MORE

Jul 4, 2018 in Java by Rishabh
• 3,620 points
1,080 views
0 votes
2 answers

Understand working of String Builder and String Buffer

Basically, StringBuffer methods are synchronized while StringBuilder ...READ MORE

Aug 29, 2018 in Java by Sushmita
• 6,920 points
1,042 views
0 votes
1 answer

Hibernate show real SQL

If you want to see the SQL ...READ MORE

Jul 5, 2018 in Java by Sushmita
• 6,920 points
1,039 views
0 votes
1 answer

How can we use wait and notify in Java?

You can refer to this: synchronized (someObject) { ...READ MORE

Jul 12, 2018 in Java by sophia
• 1,400 points
711 views
0 votes
1 answer

What is an efficient way to implement a singleton pattern in Java?

Use an enum: public enum Foo { ...READ MORE

Jul 6, 2018 in Java by Akrati
• 3,190 points
962 views
0 votes
2 answers

Explain the functionality of Math.random() method.

You can use java.util.Random class. int myNumber = ...READ MORE

Aug 3, 2018 in Java by Sushmita
• 6,920 points
1,356 views
0 votes
1 answer

What's the difference between SoftReference and WeakReference in Java?

Weak references A weak reference, simply put, is a ...READ MORE

Jun 12, 2018 in Java by Rishabh
• 3,620 points
1,966 views
0 votes
1 answer

Sort a HashMap in Java

Convert hashmap to an ArrayList with a ...READ MORE

Jul 13, 2018 in Java by Daisy
• 8,140 points
661 views
0 votes
2 answers

Avoiding != null statements

public String getPostcode(Person person) { ...READ MORE

Aug 20, 2018 in Java by Daisy
• 8,140 points
869 views
0 votes
1 answer

What is the array initialization syntax when not in a declaration?

Probably you'd have to ask the Java ...READ MORE

Jul 13, 2018 in Java by Akrati
• 3,190 points
600 views
0 votes
1 answer

How to resolve the java.net.ConnectException in Java?

If you are getting java.net.ConnectionException, it means ...READ MORE

Jun 4, 2018 in Java by Akrati
• 3,190 points
2,259 views
0 votes
2 answers

Send HTTP request in Java

import com.google.api.client.http.GenericUrl; import com.google.api.client.http.HttpRequest; import com.google.api.client.http.HttpResponse; import com.google.api.client.http.HttpTransport; import com.google.api.client.http.javanet.NetHttpTransport; import java.io.IOException; import ...READ MORE

Aug 3, 2018 in Java by samarth295
• 2,220 points
1,752 views
0 votes
2 answers

How to call one constructor from another in Java?

public class Cons { public static Cons ...READ MORE

Jul 24, 2018 in Java by Akrati
• 3,190 points
1,564 views
0 votes
2 answers

How can we remove an element from an array in Java?

You can use ArrayUtils class remove method ...READ MORE

May 24, 2018 in Java by UshaK
2,744 views
0 votes
1 answer

java.lang.UnsupportedClassVersionError: Bad version number in .class file. How to solve this?

I've learned that error messages like this ...READ MORE

Jul 4, 2018 in Java by Annie
• 240 points
928 views
0 votes
3 answers

How to reverse a string in java?

public static String reverse(String s) { ...READ MORE

Aug 17, 2018 in Java by samarth295
• 2,220 points
1,576 views
+1 vote
1 answer

Remove objects from an array in Java?

We can use external libraries: org.apache.commons.lang.ArrayUtils.remove(java.lang.Object[] array, int ...READ MORE

Jun 26, 2018 in Java by scarlett
• 1,290 points
1,189 views
0 votes
1 answer

how to play sound in java?

 The following code will work fine. But I ...READ MORE

Jun 20, 2018 in Java by scarlett
• 1,290 points
1,492 views
0 votes
1 answer

How to get the name of the currently executing method?

Thread.currentThread().getStackTrace() will usually contain the method you’re ...READ MORE

Jul 5, 2018 in Java by Daisy
• 8,140 points
839 views
0 votes
0 answers

How to populate a ListView using an ArrayList?

I want to populate the data coming ...READ MORE

Jun 30, 2018 in Java by misc.edu04
• 1,450 points
1,107 views
0 votes
2 answers

How may I programmatically determine operating system in Java?

Use the following program public class Osname {        public ...READ MORE

Jul 6, 2018 in Java by Priyaj
• 58,020 points
742 views
0 votes
2 answers

How to get input from user using System.console()?

Scanner in = new Scanner(System.in); int i = ...READ MORE

Aug 2, 2018 in Java by Sushmita
• 6,920 points
1,101 views
0 votes
1 answer

How to get a platform-dependent new line character in Java?

If you are using Java 1.5 or ...READ MORE

Jul 3, 2018 in Java by Akrati
• 3,190 points
902 views
0 votes
1 answer

Is there any way to write content of Java InputStream to an OutputStream?

org.apache.commons.io.IOUtils from Apache has a method called copy(InputStream,OutputStream).which does ...READ MORE

Jul 6, 2018 in Java by sharth
• 3,370 points
757 views
0 votes
1 answer

How does omitting curly braces in Java program, effect the code ?

Using braces makes the code more maintainable ...READ MORE

May 14, 2018 in Java by Rishabh
• 3,620 points
3,034 views
0 votes
1 answer

Measure time elapsed in Java?

This is also a way to work ...READ MORE

Jul 4, 2018 in Java by scarlett
• 1,290 points
854 views
0 votes
2 answers

What is the difference between = and equals()?

The equals() method compares the "value" inside String instances ...READ MORE

Aug 13, 2018 in Java by Daisy
• 8,140 points
1,404 views
+1 vote
3 answers

How to convert a List to an Array in Java?

Either: Foo[] array = list.toArray(new Foo[list.size()]); or: Foo[] array = ...READ MORE

Aug 7, 2018 in Java by Akrati
• 3,190 points
1,141 views
0 votes
1 answer

How to pad an integer with zeros on the left in Java?

Use java.lang.String.format() method. String.format("%05d", number ...READ MORE

May 31, 2018 in Java by Daisy
• 8,140 points
2,274 views
0 votes
2 answers

Remove duplicate elements from an ArrayList in Java

List<String> al = new ArrayList<>(); // add elements ...READ MORE

Jul 26, 2018 in Java by Sushmita
• 6,920 points
1,681 views
0 votes
1 answer

NoClassDefFoundError in Java

Can’t tell you the exact reason as ...READ MORE

May 25, 2018 in Java by v.liyyah
• 1,300 points
2,501 views
0 votes
1 answer

Is it possible to create a memory leak with Java

Here's a good way to create a memory ...READ MORE

May 31, 2018 in Java by Parth
• 4,640 points
2,268 views
0 votes
1 answer

How to get the Generic type of class at run time?

public class GenericClass<T> { ...READ MORE

Jul 2, 2018 in Java by Akrati
• 3,190 points
830 views
0 votes
3 answers

How to sort an array in java?

import java.util.Arrays; public class Sort { ...READ MORE

Aug 24, 2018 in Java by Parth
• 4,640 points
1,220 views