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December 2021

How to Fix the Unsupported Operation Exception Error in Java

An UnsupportedOperationException is a runtime exception in Java that occurs when a requested operation is not supported. For example, if an unmodifiable List is attempted to be modified by adding or removing elements, an UnsupportedOperationException is thrown. This is one of the common exceptions that occur when working with Java collections such as List, Queue, Set and Map. The UnsupportedOperationException is a member of the Java Collections Framework.

How to Handle the Incompatible Types Error in Java

Variables are memory containers used to store information. In Java, every variable has a data type and stores a value of that type. Data types, or types for short, are divided into two categories: primitive and non-primitive. There are eight primitive types in Java: byte, short, int, long, float, double, boolean and char. These built-in types describe variables that store single values of a predefined format and size.

The Ultimate Guide to Logging in Python

Logging is used to track events that happen when an application runs. Logging calls are added to application code to record or log the events and errors that occur during program execution. In Python, the logging module is used to log such events and errors. An event can be described by a message and can optionally contain data specific to the event. Events also have a level or severity assigned by the developer. Logging is very useful for debugging and for tracking any required information.

Java Guides: How to Handle the Unclosed String Literal Error

Strings are a fundamental data type in most modern general-purpose programming languages. In Java, strings are defined as character sequences and are represented as immutable objects of the class java.lang.String which contains various constructors and methods for creating and manipulating strings . Below is an example of the string literal "rollbar" being assigned to two different variables a and b which both reference the same (automatically interned) String object.

How to Fix Method/Constructor X in Class Y Cannot be Applied to Given Types in Java

In computer programming, a function is a set of instructions that can be invoked to perform a particular task. In object-oriented programming (OOP), a method is a function that is typically associated with an object and models its behavior . In Java, methods can also be static, in which case they are part of a class definition and do not require an object to be created before they are invoked.

Rollbar Log4J CVE-2021-44228 ("Log4Shell") Community Update

Your data is safe with Rollbar. A zero day in the Java ecosystem was discovered that could exploit Apache’s Log4J library. The vulnerability can, potentially, impact users of Rollbar’s Java SDK if they selected Log4J for their project. We recommend that all projects that are dependent on Log4J upgrade their dependencies so they require a version at/after 2.16.0.

How to Handle Unhashable Type List Exceptions in Python

The Python TypeError: unhashable type: 'list' usually means that a list is being used as a hash argument. This error occurs when trying to hash a list, which is an unhashable object. For example, using a list as a key in a Python dictionary will cause this error since dictionaries only accept hashable data types as a key. The standard way to solve this issue is to cast a list to a tuple, which is a hashable data type.

How to Catch Multiple Exceptions in Python?

When a program encounters an exception during execution, it is terminated if the exception is not handled. By handling multiple exceptions, a program can respond to different exceptions without terminating it. In Python, try-except blocks can be used to catch and respond to one or multiple exceptions. In cases where a process raises more than one possible exception, they can all be handled using a single except clause.

Resolving TypeError: "X" is Not a Constructor in JavaScript

A constructor is a special function that creates and initializes an object instance of a class. In JavaScript, a constructor gets called when an object is created using the new keyword. The purpose of a constructor is to create a new object and set values for any existing object properties.