AP CSA Strings Review

Given the following code segment, which of the following is true?

String s1 = new String("Hi There");

String s2 = new String("Hi There");

String s3 = s1;

I. (s1 == s2)

II. (s1.equals(s2))

III. (s1 == s3)

IV. (s2.equals(s3))

• II and IV

• II, III, and IV

• I, II, III, IV

• II only

• IV only

What does the following code print?

System.out.println("13" + 5 + 3);

• 21

• 1353

• It will give a run-time error

• 138

• It will give a compile-time error

  Check MeCompare me

After the following code is executed, which of I, II and/or III will evaluate to true?

String s1 = "xyz";

String s2 = s1;

String s3 = s2;

I. s1.equals(s3)

II. s1 == s2

III. s1 == s3

• I, II, III

• I only

• II only

• III only

• II and III only

What is output from the following code?

String s = "Georgia Tech";

String s1 = s.substring(0,7);

String s2 = s1.substring(2);

String s3 = s2.substring(0,3);

System.out.println(s3);

• org

• eor

• eorg

• orgi

• You will get an index out of bounds exception

Given the following code segment, what is the value of s1 after the code executes?

String s1 = "Hi There";

String s2 = s1;

String s3 = s2;

String s4 = s1;

s2 = s2.toLowerCase();

s3 = s3.toUpperCase();

s4 = null;

• null

• hi there

• HI THERE

• Hi There

• hI tHERE

There is a method called checkString that determines whether a string is the same forwards and backwards. The following data sets can be used for testing the method. What advantage does Data Set 2 have over Data Set 1?

Data Set 1 Data Set 2

aba bcb

abba bcd

aBa

• Data Set 2 contains one string which should return true and one that should return false.

• All strings in Data Set 2 have the same number of characters.

• The strings in Data Set 2 are all lowercase

• Data Set 2 contains fewer values than Data Set 1.

• There are no advantages.

Given the following code segment, what is in the string referenced by s1?

String s1 = "xy";

String s2 = s1;

s1 = s1 + s2 + "z";

• xyz

• xyxyz

• xy xy z

• xy z

• z

What is the value of len after the following executes?

String s1 = "Hey, buddy!";

int len = s1.length();

• 8

• 10

• 11

• 43

What is the value of pos after the following code executes?

String s1 = "ac ded ca";

int pos = s1.indexOf("d");

• 3

• 4

• 5

• -1

What is the value of s1 after the following code executes?

String s1 = "Hey";

String s2 = s1.substring(0,1);

String s3 = s2.toLowerCase();

• Hey

• he

• H

• h