Runtime stack mechanism in Java

Every time you need to run a process, code or thread in Java, a runtime stack is created to store the operations performed when the thread is executed.

Each entry in the runtime stack is called a stack frame or activation record. Once a process calls a function, the data associated with it is removed from the runtime stack.

When all functions have been called, the runtime stack will be empty. This means it needs to be removed from memory.

At this point, the runtime stack is destroyed, and then the thread is terminated.

Termination of a thread can occur when the thread completes (voluntary) or forced (abnormal termination).

The destruction order of elements in the runtime stack is opposite to the creation order of runtime task entries.

When the thread runs normally and completes execution, the main function is called and its entry is stored in the runtime stack. Similarly, other functions (if any) are called and their entries are stored. When function execution completes, that's when the entry is removed from the runtime stack. The last function executed is the function of the first deleted entry.

When a thread terminates abnormally, it means that all lines of code cannot be executed successfully. This means that an exception is thrown when an error is encountered. The following is an example:

Example

Online demonstration

public class Demo{
   public static void main(String[] args){
      test();
   }
   public static void test(){
      test_2();
      System.out.println("This is a test method.");
   }
   public static void test_2(){
      System.out.println(45/0);
      System.out.println("This is a method that divides 10 by 0.");
   }
}

Output

Exception in thread "main" java.lang.ArithmeticException: / by zero
at Demo.test_2(Demo.java:14)
at Demo.test(Demo.java:9)
at Demo.main(Demo.java:5)

A class named Demo contains the main function, in which the 'test' function. The 'test' function is defined, in which the 'test_2' function is called. A function called 'test_2' is defined in which an attempt is made to divide a number by 0. This results in an exception being printed on the console. Therefore, control does not reach the 'println' line to print the error message.

The above is the detailed content of Runtime stack mechanism in Java. For more information, please follow other related articles on the PHP Chinese website!