How-to articles, tricks, and solutions about JAVA

To sort an ArrayList in Java, you can use the Collections.sort method.

Yes, you can catch multiple exceptions in the same catch clause in Java.

To convert a byte array to a string and back to a byte array in Java, you can use the getBytes method of the String class and the getBytes method of the Charset class.

The "stale element reference" error in Selenium WebDriver occurs when an element that was previously found on the webpage is no longer attached to the DOM (Document Object Model) and is therefore no longer accessible through the browser.

To set the time zone of a java.util.Date object in Java, you can use the Calendar class.

SOAP (Simple Object Access Protocol) and REST (Representational State Transfer) are two different styles of web services that can be used to expose the functionality of a web-based system over the internet.

Java does not have an unsigned int data type.

To check the type of a variable in Java, you can use the instanceof operator.

To import classes in a JSP (JavaServer Page) file, you can use the <%@ page import="package.class" %> directive.

To get the current stack trace in Java, you can use the getStackTrace method of the Thread class or the getStackTrace method of the Throwable class.

To add leading zeroes to a number in Java, you can use the format method of the String class, along with a format string that specifies the desired length and padding character.

The Oracle JDK (Java Development Kit) and the OpenJDK are two implementations of the Java SE (Standard Edition) platform.

To decompile DEX (Dalvik Executable) files into Java source code, you can use a DEX decompiler such as JD-GUI or DEX2JAR.

If you see the error "Failed to load JNI shared library" when starting Eclipse, it means that the Java Native Interface (JNI) library required by Eclipse cannot be found or loaded.

To remove all white spaces from a string in Java, you can use the replaceAll method of the String class, along with a regular expression that matches any white space character (including spaces, tabs, and line breaks):

In Java, a class can only extend from one superclass (i.e., it can only have one direct parent class).

The @JsonProperty annotation is used to specify the property name in a JSON object when serializing or deserializing a Java object using the Jackson library.

To add an element to an array in Java, you can use one of the following methods:

To upload files to a server using JSP/Servlet, you can use the following steps:

To convert a String object to a Boolean object in Java, you can use the Boolean.valueOf method:

If you get the error "class has been compiled by a more recent version of the Java Environment", it means that you are trying to run a class file that was compiled with a newer version of Java than the one you have installed.

Apache Camel is an open-source integration framework that provides a uniform interface for integrating various applications and protocols.

To join array elements with a separator in Java, you can use the join method from the String class.

To get the current time in Java, you can use the Instant class from the java.time package.

If you want to ignore new fields on JSON objects when using Jackson, you can use the @JsonIgnoreProperties annotation on your Java object.