Introduction to Java Methods: Definition, Invocation, and Parameter Passing – Get It After Reading

This article introduces the basic knowledge of Java methods, including definition, invocation, and parameter passing. A method is a tool for encapsulating repeated code, which can improve reusability. Definition format: `Modifier ReturnType MethodName(ParameterList) { MethodBody; return ReturnValue; }`. Examples include a parameterless and returnless `printHello()` method (to print information) and a parameterized and returnable `add(int a, int b)` method (to calculate the sum of two numbers). Invocation methods: Static methods can be directly called using `ClassName.MethodName(ActualParameters)`, while non-static methods require an object. For example, `printHello()` or `add(3,5)`. Parameter passing: Basic types use "pass-by-value", where modifications to formal parameters do not affect actual parameters. For instance, in `changeNum(x)`, modifying the formal parameter `num` will not change the value of the original variable `x`. Summary: Methods enhance code reusability. Mastering definition, invocation, and pass-by-value is the core. (Note: The full text is approximately 280 words, covering core concepts and examples to concisely explain the key points for Java method beginners.)