Which of the following appear in a method's signature? Mark all that apply
1. Method name
2. Return type
3. Parameter types
4. Access modifier
5. Exception types
The correct answers are 1, 2, 3, and 4. The method name, return type, parameter types, and access modifier appear in a method's signature. Exception types are not part of the method's signature, but they may be part of the method's declaration or definition.
Which of the following is a variable's scope in a Java library?
The possible scopes for variables in a Java library are:
1. Local scope
2. Instance scope (also known as object scope)
3. Class scope (also known as static scope)
These scopes determine the accessibility and lifespan of a variable within a Java library.
What does a constructor return?
A constructor does not explicitly return a value. In Java, a constructor is a special method that is used to initialize objects of a class. It has the same name as the class and does not have a return type, not even void.
When you create an instance of a class using the new keyword and the class's constructor, the constructor is invoked to initialize the object's state. It sets up the initial values of the object's instance variables. The constructed object is then returned as the result of the constructor invocation.
To determine which options appear in a method's signature, we need to first understand what a method's signature is. In programming, a method's signature refers to the unique combination of its name and parameter types.
Here are the potential options that could appear in a method's signature:
1. Method name: The name assigned to the method, which is used to uniquely identify it in the code.
2. Return type: The data type of the value that the method returns to the caller, if any. It specifies the type of the value that the method is expected to provide as its result.
3. Access modifier: Specifies the accessibility of the method, such as public, private, or protected. It determines which parts of the code can access the method.
4. Parameter list: The list of parameters, if any, that are passed to the method. These parameters specify the data types and names of the values that the method requires as inputs.
So, in summary, the options that appear in a method's signature are the method name, return type, and parameter list. The access modifier does not appear in a method's signature.
To determine which elements appear in a method's signature, we need to understand the components of a method in programming. In general, a method's signature includes the following elements:
1. Method name: The name of the method, which is used to identify and call the method.
2. Return type: The data type of the value returned by the method. It represents the type of value that will be returned to the caller of the method.
3. Parameters: The inputs that the method accepts when it is called. Parameters consist of a data type followed by a parameter name, and multiple parameters can be separated by commas.
Now let's look at the options you provided and check which elements are part of a method's signature:
A. Method body: The actual code inside the method that defines its behavior. The method body is not considered part of a method's signature.
B. Access modifiers: These specify the visibility and accessibility of the method. Access modifiers (e.g., public, private, protected) are not part of a method's signature.
C. Return type: Yes, the return type is part of a method's signature. It indicates the type of value the method will return.
D. Method name: Yes, the method name is part of a method's signature as it identifies the method.
E. Parameters: Yes, the parameters are part of a method's signature. They define the inputs that the method expects when it is called.
Therefore, the elements that appear in a method's signature are the return type (C), method name (D), and parameters (E).