Csci 1301, Lab 7
2008.06.30
ReverseString.java
Today's lab involves using the length, charAt, and concat String methods to
reverse a String that you've read from the user. You’ll also be writing a static method
other than main. This is our first taste of method decomposition. I’ve provided a skeleton
program. You’ll need to fill in a few bits in the main method and write the body of the
reverse method.
In the main method, you'll need to use a Scanner to read the original line of text.
Then, you’ll want to call the static method that you’ll be writing: reverse. Remember, it
returns a String!
In the reverse method, beginning with an empty result String, use a for loop to
read the original String backwards character by character. On each pass through the for
loop use the concat method, not the +-operator, to add the appropriate char to the result.
You will likely discover a problem: the concat method only takes String arguments!
Fortunately, the Character.toString static method takes a char argument and returns that
character as a String, so you can use it to turn each char into a length-one String that you
can concatenate to the result. Finally, remember that concat does not modify the original
String, it creates a new String, so store the result appropriately! Oh, and don’t forget to
return the result.
Here's an example of a run of the program:
> Enter a String of text:
> Blah, blah, blah!
> Reverse String of text:
> !halb ,halb ,halB