AP CSA 1.10 FRQ Practice: Static Call Chain

Unit 1: Using Objects and Methods · Lesson 1.10 · FRQ Practice

Static Call Chain

A free response question in the shape the exam uses: a stated contract, four rubric parts, and no main method handed to you. Worth 4 points.

Back to the Lesson 1.10 pageAll Unit 1 lessons

Why this question is worth four points

A class method is called on the CLASS, not on an object, and the return value is the only thing that comes back. The most common lost point in this topic is a call whose result is thrown away: Math.max(a, b); on its own line computes the maximum and discards it.

What you are given

Three variables are declared and assigned for you: int first, int second and String code.

The question

  1. (a) Print the larger of first and second.
  2. (b) Print the square root of the larger value.
  3. (c) Print the length of code.
  4. (d) Print code with every letter in upper case.

What the reader is looking for

  1. Write a code segment that prints four lines in rubric order.
  2. Math and Integer methods are called on the class. String methods like length and toUpperCase are called on the object.
  3. Every one of these RETURNS a value. A call on a line by itself computes an answer and throws it away.

Worked examples

These show what a correct answer prints. There are more cases you cannot see, and they use different values, so an answer built around just these numbers will fail.

Example 1 is given
int first = 9;
int second = 16;
String code = "delta";
Example 1 output
16
4.0
5
DELTA
Example 2 is given
int first = 2;
int second = 1;
String code = "Ok";
Example 2 output
2
1.4142135623730951
2
OK

Your answer

Main.java

Input for the Run button

How this is scored: your answer runs against every test case, and the fraction it passes becomes your score out of 4. That is not how a human AP reader marks a rubric, so treat the score as a check on whether your code works, and the rubric above as the thing you are actually practising.


  

  
Stuck?

    
Hint 1
Store the larger value once and reuse it. Part (a) and part (b) both need it, and calling Math.max twice is two chances to swap the arguments.

    
Hint 2
Math.sqrt returns a double, so the answer prints with a decimal point even when the root is a whole number. 16 gives 4.0.

    
Hint 3
toUpperCase does not change the String it is called on, because a String cannot be changed. It RETURNS a new one, so code.toUpperCase(); on its own line does nothing at all.



  
Where to go next

  

    Rework the Lesson 1.10 page
    Try the from-scratch exercise for this lesson
    Try the debugging exercise for this lesson
  


  
  






  

















  
Get in Touch

  
Whether you're a student, parent, or teacher — I'd love to hear from you.







  
Just want free AP CS resources?

  

    Enter your email below and check the subscribe box — no message needed.
    Students get daily practice questions and study tips. Teachers get curriculum resources and teaching strategies.
  







  
  Typically responds within 24 hours






  
✓

  
Message Sent!

  

    Thanks for reaching out. I'll get back to you within 24 hours.
  







  


  

    
    

    
    

      

        
        
      

      

        
        
      

    


    
    

      

        
        
      

      

        
        
      

    


    
    

      

        
        
      

      

        
        
      

    


    
    

      
🏫 Welcome, fellow educator!

      

        I offer curriculum resources, practice materials, and study guides designed for AP CS teachers.
        Let me know what you're looking for — whether it's classroom materials, a guest speaker,
        or Teachers Pay Teachers resources.
      

    


    
    

      
      
    


    
    

    
    

      
    

  







  

    ✉
    
Email

    
[email protected]

  

  

    📚
    
Courses

    
AP CSA, CSP, & Cybersecurity

  

  

    ⏱
    
Response Time

    
Within 24 hours

  







  Prefer email? Reach me directly at
  [email protected]