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What does the invoke() method in Java do?

What does the invoke() method in Java do?

Reflection provides a method for invoking strategies on a category. Typically, this would only be necessary if it is not possible to cast an instance of the class to the desired type in a non-reflective code
There are no functions in JAVA. They are called methods.
A operate could be a piece of code that's known as by name. It will be passed knowledge to work on (i.e. the parameters) and may optionally come back knowledge (the comeback value). All knowledge that's passed to a operate is expressly passed.
A method could be a piece of code that's known as by a reputation that's related to Associate in the Nursing object. In most respects it's a twin of a operate apart from 2 key differences:
A method is implicitly passed the thing on that it absolutely was known as.
A method is ready to work on the knowledge that's contained inside the category (remembering that Associate in the Nursing object is Associate in Nursing instance of a category - the category is that the definition, the object is an instance of that data).
What does the invoke() method in Java do
learnwitharyan

Methods are invoked with
The first argument is that the object instance on that this specific methodology is to be invoked. (If the tactic is, static the first argument should be null.)
Subsequent arguments are the method's parameters. If the underlying methodology throws the associate exception, it will be wrapped by
The method's original exception could also be retrieved victimization the exception chaining
Invoke method is of Method Class
This class is used for Reflection purpose
The Reflection is the concept via which a Java Class can be called and its methods can be used even if it is not in the package but at runtime
Let's say I have given a console and JDK is installed on it
I run a program however I do want to use a number of its practicality I will do that to use its practicality. That's Why public private protected are used in order to hide the variables from external use.
That's also how the Eclipse or NetBeans knows that you seek some class to use when you type partial and click on ctrl+space.
This software also uses internally these packages...
Their area unit varied ways that to invoke methodology in java and it depends on demand that however you wish to access it and the way necessary it's in context.
Following area unit many examples of invoking methodology by a totally different method.
1) If you wish to access it by object then access it by making new object OR victimization existing one.


For example,

public class MethodInvoke
}
public class TestMethodInvoke
}
If you wish to load it whereas category loading and access it while not victimization object, define it as static


For example,

public class MethodInvoke
}
public class TestMethodInvoke
}
Another way to invoke methodology by victimization reflection API, which is used as runtime invocation.

Method Invocation is done in two ways-

⇨Statically Through Class name

In this, a method must be declared static. If it's static which means it'll be loaded before long once the category is loaded by JVM. It stays in a static area ( method area) so it is called with a class name.

E.g public static void show()

public static void main(String args[])

Through class instance

In this, the tactic is termed by the associated instance of the category. And the methodology is formed within the heap space. So so as to access that you simply should be in heap memory, therefore, object creation happens in heap, therefore, instance calls it from a heap.
e.g

public void show()

public static void main(String args[])
of sophistication.
obj.show();// output - Show
}

Method 1:
You could access a technique by making associate object once the tactic is at intervals another category.
public ClassA
}
when you want to access the method print() within another class
public ClassB
}
What is an associate object associated why can we produce an object in java?

Method 2:
You could conjointly access a technique with none object creation
i) once you area unit planning to invoke the tactic at intervals identical category
public ClassA
public void doSomething()
}
ii) By declaring the method as static
By declaring the method as static you could access the method anywhere from your project like class name.method_name like
public ClassA
}
when you want to access the method print() within another class
public ClassB
}
If the performance is non-static we have a tendency to use object of sophistication to the decision is as:
class Hel
public void main (String args[])
}
If the performance is static we will use 2 ways:
A) if the tactic is in the same category then:
class XYZ
public static void main (String args[])
}
B) if the tactic is in several categories then :
class abc}
However opposed to the reason in my book, the 10 years solved papers wrote the answer as :
Call by reference
Call by value
However, despite this I stand that my answer is correct.
What does the invoke() method in Java do? What does the invoke() method in Java do? Reviewed by Raj Aryan on April 05, 2019 Rating: 5

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