Reta Final DATAPREV 2026: O que a FGV mais cobra em JAVA?

Summary

Key Points

• Java is a high-level programming language derived from C, known for its portability as a hybrid language. 3:08
• Java's portability is achieved by compiling source code into platform-independent bytecodes, which are then executed by a Java Virtual Machine (JVM) within a Java Runtime Environment (JRE) specific to each platform. 5:09
• The '+' operator in Java performs string concatenation if at least one operand is a string, otherwise it performs arithmetic addition. 6:54
• For a Java class to be executable, it must contain a `public static void main(String[] args)` method, which serves as the entry point for program execution. 8:12
• The `final` modifier is used to declare an attribute (or method/class) whose value, once initialized, cannot be changed, effectively creating a constant. 14:27
• Object-Oriented Programming (OOP) in Java is guided by four pillars: abstraction (classes and objects), encapsulation, inheritance, and polymorphism. 17:19
• Method overloading allows multiple methods within a class to share the same name, provided they have different numbers or types of parameters, enabling flexible function calls. 23:21
• Encapsulation is achieved by making an object's attributes private and providing public methods (getters and setters) to control access and modification, ensuring data integrity and adherence to business rules. 32:20
• Java Streams provide a powerful way to process collections of data through a sequence of operations like filtering, mapping, and reducing (e.g., summing) in a declarative style. 33:17
• Java supports various inheritance mechanisms, including regular classes, abstract classes (cannot be instantiated but promote inheritance), final classes (can be instantiated but prevent inheritance), and sealed classes (which explicitly restrict their permitted subclasses). 40:42