-------Interpreter for Java 23 design Patterns

One, interpreter mode (interpreter)
Interpreter mode is generally used in the development of the compiler in OOP development, so the application surface is narrower.

The context class is a contextual class, plus and minus are used to calculate the implementation, the code is as follows:

1. Public interface Expression {
2. public int interpret (context context);
3. }

1. public class Plus implements Expression {
3. @Override
4. public int interpret (context context) {
5. Return Context.getnum1 () +context.getnum2 ();
6. }
7. }

1. public class minus implements Expression {
3. @Override
4. public int interpret (context context) {
5. Return Context.getnum1 ()-context.getnum2 ();
6. }
7. }

2. public class Context {
6. private int num1;
8. private int num2;
12. Public Context (int num1, int num2) {
14. THIS.NUM1 = NUM1;
16. this.num2 = num2;
18. }
22. public int getNum1 () {
24. return NUM1;
26. }
28. public void setNum1 (int num1) {
30. THIS.NUM1 = NUM1;
32. }
34. public int getNum2 () {
36. return num2;
38. }
40. public void setNum2 (int num2) {
42. this.num2 = num2;
44. }
50. }

1. public class Test {
3. public static void Main (string[] args) {
5. Calculate the value of a 9+2-8
6. int result = new minus (). Interpret (new Context (New Plus ()
7. . Interpret (new Context (9, 2)), 8));
8. SYSTEM.OUT.PRINTLN (result);
9. }
10. }

Finally output the correct result: 3.

Basically, the interpreter pattern is used to make all kinds of interpreters, such as regular expressions and so on!

Reprinted from Https://www.cnblogs.com/maowang1991/archive/2013/04/15/3023236.html

-------Interpreter for Java 23 design Patterns