Can you you use conditional statements in other conditional statements?

My question is simple, will the following code work, if it can't is there a way to accomplish the same effect

int day = 5; 
    String dayString; 

    switch (if (day > 0) { 
    case 1: 
        dayString = "Monday"; 
        day++;
        break; 
    case 2: 
        dayString = "Tuesday"; 
        day++;
        break; 
    case 3: 
        dayString = "Wednesday"; 
        day++;
        break; 
    case 4: 
        dayString = "Thursday"; 
        day++;
        break; 
    case 5: 
        dayString = "Friday"; 
        day++;
        break; 
    case 6: 
        dayString = "Saturday"; 
        day++;
        break; 
    case 7: 
        dayString = "Sunday"; 
        day++;
        break; 
    default: 
        dayString = "Invalid day"; 
        day++;
        break; 
    } 
    System.out.println(dayString); 

The output should be friday, basically my question is can you put if statements or while or for or do or other statements within the parameters of the respective statements.