The behavior of the 5th Chapter object

1. All method calls are maintained in a structure called the call stack, and the currently executing method is at the top of the call stack. When the current method executes, it is removed from the top of the call stack, and the previous method in the stack is returned by the control process.

The 2.main () method is always at the bottom of the call stack.

3. If a Java program is a multithreaded application, it can have multiple call stacks.

4. When a method is executing, three cases (1) of the method return a value. (2) The method does not return a value. (3) method throws an exception to the caller of the method.

5. The process of copying data between method invocations is called call by value, and is the only option.

6. The only limitation caused by a value call is that the method cannot change the point of the reference.

7. In a large Java program, there can be many classes, but there must be only one class with the main () method.

8. The only time the constructor is called is when the object is instantiated. The constructor is similar to a method, but it is not a method.

9. Each class must have a constructor.

In the 10.Java class, once the class's definition explicitly defines one or more construction methods, the default construction method is no longer provided by the system.

11. Parameters: Variables that are used to receive externally-passed data when the method is invoked.

12. Arguments: Data that is actually passed to the function form parameter when the function is called.

13. Inside each member method, there is a this reference variable that points to the object that called the method.

14.java.lang----contains some of the core classes of the Java language, such as String, Math, Integer, System, and thread, to provide common functionality.

The 15.java.net----contains classes that perform network-related operations.

The 16.java.io----contains classes that can provide multiple input/output functions.

The 17.java.util----contains utility classes, such as defining system attributes and using functions related to date calendars.

The behavior of the 5th Chapter object