Fundamental Data Types - Java Concepts - page 217

Because a is a string, n is converted from the integer 7 to the string Ð7Ñ . Then the
two strings ÐAgentÑ and Ð7Ñ are concatenated to form the string ÐAgent7Ñ .

Whenever one of the arguments of the + operator is a string, the other argument is
converted to a string.

This concatenation is very useful to reduce the number of System , out.print
instructions. For example, you can combine

System.out.print("The total is ");
System.out.println(total);

to the single call

System.out.println("The total is " + total);

The concatenation ÐThe total is Ñ + total computes a single string that
consists of the string ÐThe total is Ñ , followed by the string equivalent of the
number total .

Sometimes you have a string that contains a number, usually from user input. For
example, suppose that the string variable input has the value Ð19Ñ . To get the
integer value 19 , you use the static parseInt method of the Integer class.

int count = Integer.parseInt(input);
// count is the integer 19

158
159

Figure 3

String Positions

To convert a string containing floating-point digits to its floating-point value, use the
static parseDouble method of the Double class. For example, suppose input is
the string Ð3.95Ñ .