Which Design Pattern Is Suitable

Now I have a class A. 
I need to procee A with different method on the basis of some attributes of A. for example:

Code: 
      
class A   
{   
string key;   
string value;   
}  
    
class A
{
string key;
string value;
}
 

And I have five method, 
A process1(A&) 
A process2(A&) 
A process3(A&) 
A process4(A&) 
A process5(A&) 

when A attribute key is "a", I need to process A with {process1, process2, process5}; 
when A attribute key is "b", I need to process A with {process1, process2}; 
when A attribute key is "e", I need to process A with {process1, process3, process5}; 
when A attribute key is "f", I need to process A with {process1, process4, process5}; 

And I have a config file to record these rules. 

So I want to know which design pattern suits my question?

Solution:

One solution would be to represent those processes as functions/commands and composing them in a collection and pass it around. 

Code:

//interface representing the command/function. Accepts one argument of type T and returns an object of type R   
interface Function1<T, R> {   
  R apply(T arg0);   
}   
  
class A {   
  final private String key;   
  final private String value;   
     
  public A(String key, String value) {   
    this.key = key;   
    this.value = value;   
  }   
  
  public String getKey() {   
    return key;   
  }   
  
  public String getValue() {   
    return value;   
  }   
     
}   
  
/*...Ignored boilerplate codes ...*/  
  
public static void main(String[] args) {   
    //Wrap and create composition over methods process1, process2 ... process5   
  
    Function1<A, A> process1 = new Function1<A, A>() {   
      @Override public A apply(A a) {   
        System.out.println("am executing process1");   
        // Call some process1(a) and return an object of A   
        return null;   
      }   
    };   
    Function1<A, A> process2 = new Function1<A, A>() {   
      @Override public A apply(A a) {   
        System.out.println("am executing process2");   
        // Call some process2(a) and return an object of A   
        return null;   
      }   
    };   
    Function1<A, A> process3 = new Function1<A, A>() {   
      @Override public A apply(A a) {   
        System.out.println("am executing process3");   
        // Call some process3(a) and return an object of A   
        return null;   
      }   
    };   
    Function1<A, A> process4 = new Function1<A, A>() {   
      @Override public A apply(A a) {   
        System.out.println("am executing process4");   
        // Call some process4(a) and return an object of A   
        return null;   
      }   
    };   
    Function1<A, A> process5 = new Function1<A, A>() {   
      @Override public A apply(A a) {   
        System.out.println("am executing process5");   
        // Call some process5(a) and return an object of A   
        return null;   
      }   
    };   
  
    Map<String, List<Function1<A,A>>> mapping = new HashMap<String, List<Function1<A,A>>>();   
    mapping.put("a", Arrays.asList(process1, process2, process5));   
    mapping.put("b", Arrays.asList(process1, process2));   
    mapping.put("e", Arrays.asList(process1, process3, process5));   
    mapping.put("f", Arrays.asList(process1, process4, process5));   
  
    A a = new A("a", "value");   
    executeProcesses(mapping.get(a.getKey()), a);    
  
    /* Output:  
    am executing process1  
    am executing process2  
    am executing process5  
    */    
  }   
     
  public static void executeProcesses(List<Function1<A, A>> processes, A a) {   
    for(Function1<A, A> process: processes) {   
      process.apply(a); //If you want, you can collect the result   
    }   
  }  

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