Exercise on Strings and Methods

Part 1: For each of the following expressions, what does it produce?

1. "Hello"

2. "Hello" + "There"

3. "     Where areyou   today         ".trim()

4. "Where are you today".trim()

5. "aaaaAAAA" + "BBBBbbbb"

6. "a string".toUpperCase()

7. "Foo on".toUpperCase() + " hello"

8. "BAM BAM BAM " + "BOOM".toLowerCase()

9. "This is really long".length()

10. "Some would say this is short".length()

11. "Friends".toUpperCase() + "this has twenty eight letters".length()

12. "Big".toUpperCase().toLowerCase()

13. "What is the substring?".substring(2, 6)

14. "How many letters?".substring(10)

15. "This is a tricky one".toUpperCase().substring(5, 10).length()

16. "I Love Lucy".lastIndexOf('L')
    • Do you see how the notation for characters differs from that of strings?

17. "Animal farm".substring("George Orwell".lastIndexOf('o'))

Part 2: For each of the following, write an expression that converts the input String(s) to the output String, subject to:

• You can apply any String methods you want (including concatenation) to the input Strings.
• You are not allowed to write an input String more than once.
  So, for example, if "Hello" is the input, you are not allowed to write answers like "Hello".toLowerCase() + "Hello".toUpperCase().
• When there is more than one input, you can use the inputs in any order you choose.

1. Input: "This is a string"
   Output: "THIS IS A STRING"   Follow this link to check your answer.

2. Inputs: "Hello there" and " Sailor"
   Output: "Hello there Sailor"

3. Inputs: "Do you know?" and "What "
   Output: "What do you know?"

4. Inputs: " What is " and " your NAME?"
   Output: "What isyour name?"   Follow this link to check your answer.

5. Inputs: "This one is " and " IS tricky"
   Output: "This one IS tricky"

6. Input: "The last"
   Output: "LAST"

7. Inputs: "FOO BAR CITY" and "This city is BIG"
Output: "foo bar CITY"

8. Inputs: "Bilbo" and "Gandalf"
   Output: "bil**G*nd*lf"

9. Inputs: "save the dolphins" and "we love them"
   Output: "THE DOLPHINS love"