Objects and Strings - A Concise and Practical Introduction to Programming Algorithms in Java - page 118

{ String tmp;
tmp=p;
p=q;
q=tmp;}

To declare and initialize a string 2 , we proceed as follows
String title= "First Hands-on Programming!";
String anotherTitle=title;
...
title="Extreme programming sounds better!"; // String can be modified

To print a string, use the regular System.out.println() function:
System.out.println(title);

Java proposes many standard functions for eciently manipulating strings. Let
us next review only the very fundamental functions that operate on String
objects.

5.6.2 Length of a string: length()

The length of a string object is defined as its number of characters. The length
of a string is reported by calling the length() method on the String object,
as shown below:

String s= "Supercalifragilisticexpialidocious";
System.out.println(s.length());

We get 34, which is the longest invented word in a song from Mary Poppins
written by the Sherman Brothers in 1964. Observe that the syntax is different
from arrays. For an array array , we get its length (that is, its number of
elements) by the following syntax: array.length . But for a string, we use the
method length() (with no argument, which explains the () parentheses).

5.6.3 Equality test for strings: equals(String str)

To test whether two strings s1 and s2 are identical or not, do not use the
regular == equality test for primitive types. Indeed testing whether two strings
are identical or not by using the comparison == will check whether the references
of these strings are identical or not. Instead, to test whether the contents of

2 Use

String objects only for moderate length strings,

otherwise use the better class StringBuffer . See Java API at

http://java.sun.com/j2se/1.4.2/docs/api/java/lang/StringBuffer.html