You wish to reverse a string, a character or word at a time.
You can reverse a string by character easily, using a
StringBuffer. There are several ways to reverse a
string a word at a time. One natural way is to use a
StringTokenizer and a
Stack is a class
java.util; see Section 7.16) that implements an easy-to-use last-in,
first-out (LIFO) stack of objects.
To reverse the characters in a string, use the
reverse( ) method.
// StringRevChar.java String sh = "FCGDAEB"; System.out.println(sh + " -> " + new StringBuffer(sh).reverse( ));
The letters in this example list the order of the sharps in the key signatures of Western music; in reverse, it lists the order of flats. Alternately, of course, you could reverse the characters yourself, using character-at-a-time mode (see Section 3.5).
A popular mnemonic or memory aid for the order
of sharps and flats consists of one word for each sharp instead of
just one letter, so we need to reverse this one
word at a
time. Example 3-4 adds each one to a
(see Section 7.16), then process the whole lot in
LIFO order, which reverses the order.
Example 3-4. StringReverse.java
String s = "Father Charles Goes Down And Ends Battle"; // Put it in the stack frontwards Stack myStack = new Stack( ); StringTokenizer st = new StringTokenizer(s); while (st.hasMoreTokens()) myStack.push(st.nextElement( )); // Print the stack backwards System.out.print('"' + s ...