Static variable are global variable which are not related to particular object,You can call a static variable directly by class name without requiring instance of class similar goes for static methods. For static variable and static method concept in detail visit, https://www.sfdc-lightning.com/2018/10/static-variable-in-salesforce.html
What is a static variable in Salesforce apex?
A static variable is static only within the scope of the Apex transaction. It’s not static across the server or the entire organization. The value of a static variable persists within the context of a single transaction and is reset across transaction boundaries.
What is a static variable in Java?
Static variable are global variable which are not related to particular object,You can call a static variable directly by class name without requiring instance of class similar goes for static methods.
When does a static variable'state'retain its value?
A static variable retains the value only during this execution context. To answer your question, the value of the variable 'state' will be retained and visible across all three classes named 'A', 'B' and 'C' only when these classes are instantiated in the same execution context.
Can a static variable be defined in a trigger?
A static variable defined in a trigger doesn’t retain its value between different trigger contexts within the same transaction, such as between before insert and after insert invocations. Instead, define the static variables in a class so that the trigger can access these class member variables and check their static values.
What are static variables?
In computer programming, a static variable is a variable that has been allocated "statically", meaning that its lifetime (or "extent") is the entire run of the program.
What is meaning of static in Salesforce?
Static variables are those which can be used without instantiating a class.Instance variables are called by object while static are called by class.Static variables and methods are not included in view state for a vf page.
What is static and non static variables in Salesforce?
Difference is that Static method can acces static variable and belongs to the class whereas Non Static method and variables can be accesed only the object of the class. Second Major difference is that Static variable can not be overridden.
What is a static variable example?
The static variable can be used to refer to the common property of all objects (which is not unique for each object), for example, the company name of employees, college name of students, etc. The static variable gets memory only once in the class area at the time of class loading.
What is the difference between global and static variable?
The difference between a static variable and a global variable lies in their scope. A global variable can be accessed from anywhere inside the program while a static variable only has a block scope.
What is the difference between static variable and dynamic variable?
Static variables (should) remain the same e.g. temperature of a water bath, k constant of a particular spring. Dynamic variables change as the experiment progresses e.g. air temperature and pressure, amount of natural light.
Why a method is static in Salesforce?
A static method is used as a utility method, and it never depends on the value of an instance member variable. Because a static method is only associated with a class, it can't access the instance member variable values of its class. A static variable is static only within the scope of the Apex transaction.
What is the difference between a static method and a non-static method in Salesforce?
non-static methods can access any static method and static variable also, without using the object of the class. In the static method, the method can only access only static data members and static methods of another class or same class but cannot access non-static methods and variables.
What is getter and setter in Salesforce?
Get (getter) method is used to pass value from controller to VF page while set (setter) is used to set the value back to controller variable. Above two methods are same and will return same results. Only their style of coding is different.
Why do we use static variables?
Static variables are used to keep track of information that relates logically to an entire class, as opposed to information that varies from instance to instance.
What are static variables and function?
Static functions can be called directly by using class name. Static variables are initialized only once. Compiler persist the variable till the end of the program. Static variable can be defined inside or outside the function. They are local to the block.
What is the difference between static and non static variables?
A static variable acts as a global variable and is shared among all the objects of the class. A non-static variables are specific to instance object in which they are created. Static variables occupies less space and memory allocation happens once. A non-static variable may occupy more space.
What is static variable?
A static variable is static only within the scope of the Apex transaction. It’s not static across the server or the entire organization. The value of a static variable persists within the context of a single transaction and is reset across transaction boundaries.
What is static method?
These items are handled in the order in which they appear in the class. A static method is used as a utility method, and it never depends on the value of an instance member variable. Because a static method is only associated with a class, it can’t access the instance member variable values of its class.
What is instance member variable?
An instance member variable is declared inside a class, but not within a method. Instance methods usually use instance member variables to affect the behavior of the method. Suppose that you want to have a class that collects two-dimensional points and plots them on a graph.
Can a static variable be accessed through an instance?
A class static variable can’t be accessed through an instance of that class. If class MyClass has a static variable myStaticVariable, and myClassInstance is an instance of MyClass, myClassInstance.myStaticVariable is not a legal expression. The same is true for instance methods.
Do local variables have to be evaluated before class names?
Local variable names are evaluated before class names. If a local variable has the same name as a class, the local variable hides methods and variables on the class of the same name. For example, this method works if you comment out the String line.
Can Apex classes be static?
In Apex, you can have static methods, variables, and initialization code. However, Apex classes can’t be static. You can also have instance methods, member variables, and initialization code, which have no modifier, and local variables.
Can you use static methods in Java?
You can use static methods and variables only with outer classes. Inner classes have no static methods or variables. A static method or variable doesn’t require an instance of the class in order to run.
How does static variable work?
How does Static variable and Static method works. Static variables are only static within the scope of the request. They’re not static across the server, or across the entire organization.
Is XX.state static?
Even though XX.state is static, it is not "server static" or "shared static.". Each transaction gets its exactly one instance of XX.state. This behavior differs from Tomcat and other server implementations that use "static" to mean "across all instances.".
Do static variables belong to a class?
Static variables do not belong to an instance of a class, they belong to the transaction's static memory area. In your first example, given: public class XX { public static boolean state = true; }. You could write this code: XX A = new XX (), B = new XX (), C = new XX (); But, you couldn't later call:
What is static variable?
Static variables are variables that belong to an overall class, not a particular object of a class. Think of a static variable to be like a global variable – its value is shared across your entire org. Any particular object’s properties or values are completely irrelevant when using static.
What does static mean in Apex?
static [stat-ik] (adjective): lacking movement, development, or vitality. Static is a special, often used keyword modifier in Apex that’s important enough to get its own post. Steve Jobs described objects as “living, breathing things that have knowledge inside them about how to do things and have memory inside them so they can remember.”.
What is static method?
Static methods, similarly, are methods that act globally and not in the context of a particular object of a class. Being global, static methods only have access to its provided inputs and other static (global) variables.