What is the difference between Java functions and Objective-C language functions?

The main difference between Java and Objective-C language functions is: Statement: Java main function uses public static void main(String[] args), Objective-C uses int main(int argc, char * argv[]); method signature : Java parameters and return values ​​are specified with parentheses, Objective-C is specified with colons outside the parentheses; Access modifiers: Java defaults to package level, Objective-C defaults to public; Return type: Java can return void, Objective-C must return a value ; Parameter passing: Java passes by value, Objective-C can pass by reference or value.

The difference between Java functions and Objective-C language functions

In Java and Objective-C languages, functions are organizational codes A block that is responsible for performing a specific task. However, there are some key differences between the two languages ​​in terms of function definition and calling.

Function declaration

• Java: Use public static void main(String[] args) Declare main function. Non-static methods do not use the static keyword.
• Objective-C: Use int main(int argc, char * argv[]) to declare the main function.

Method signature

• Java: Method parameters and return types are specified in parentheses.
• Objective-C: Method parameters and return types are specified using colons : outside parentheses.

Access Modifiers

• Java: The default access modifier is package level.
• Objective-C: The default access modifier is public.

Return type

• Java: Methods can return a value or void.
• Objective-C: methods always return a value, even void.

Parameter passing

• Java: Parameters are passed by value.
• Objective-C: Parameters are passed by reference or by value.

Practical case: Printing string

Java code:

public class Main {
    public static void main(String[] args) {
        System.out.println("Hello Java!");
    }
}

Objective-C code :

int main(int argc, char * argv[]) {
    printf("Hello Objective-C!\n");
    return 0;
}

Conclusion:

There are some syntactic and semantic differences between Java and Objective-C language functions. Understanding these differences is crucial to writing effective code in each language.

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