String is a bunch of characters in Java. It’s like having several char values in a row. To read a String value from the keyboard, you can call either next or nextLine:
- The methodnextreads up to the next blank space.
For example, with the input Barry A. Burd, the statements
String firstName = keyboard.next();
String middleInit = keyboard.next();
String lastName = keyboard.next();
assign Barry to firstName, A. to middleInit, and Burd to lastName.
- The method
nextLinereads up to the end of the current line.
For example, with input Barry A. Burd, the statement
String fullName = keyboard.nextLine();assigns Barry A. Burd to the variable fullName.
To display a String value, you can call one of your old friends, System.out.print or System.out.println. A statement like
out.print("Customer's full name: ");
displays the String value "Customer's full name: ".
You can use print and println to write String values to a disk file.
In a Java program, you surround the letters in a String literal with double quote marks.
Adding strings to things
In Java, you can put a plus sign between a String value and a numeric value. When you do, Java turns everything into one big String value. To see how this works, consider the following code.import java.util.Scanner;
import static java.lang.System.out;
class ProcessMoreData {
public static void main(String args[]) {
Scanner keyboard = new Scanner(System.in);
String fullName;
double amount;
boolean taxable;
double total;
out.print("Customer's full name: ");
fullName = keyboard.nextLine();
out.print("Amount: ");
amount = keyboard.nextDouble();
out.print("Taxable? (true/false) ");
taxable = keyboard.nextBoolean();
if (taxble) {
total = amount * 1.05;
} else {
total = amount;
}
out.println();
out.print("The total for ");
out.print(fullName);
out.print(" is ");
out.print(total);
out.println(".");
keyboard.close();
}
}
Replace the last several lines in of the code below with the following single line:
out.println("The total for " + fullName + " is " + total + ".");
Fun with word order
Write a program that inputs six words from the keyboard. The program outputs six sentences, each with the first word in a different position. For example, the output of one run might look like this:only I have eyes for you.
I only have eyes for you.
I have only eyes for you.
I have eyes only for you.
I have eyes for only you.
I have eyes for you only.