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.

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.

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.

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.

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.

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.

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.

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.

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.

PHP’s E_ERROR typically indicates a major issue with PHP. Normally, PHP may be able to recover from a lesser error and the PHP application could continue to run. However, with E_ERROR, PHP will usually outright fail and stop working entirely.