Ch1 – Displaying Strings

  1. Java Tutorial – Think Java
  2. Chapter One – The Way
  3. Ch1 – Displaying Strings

    1. Create a new file named Hello2.java.
    2. Add two println statements to the main method.
    public class Hello2 {
  public static void main(String[] args) {
    System.out.println("Hello, World!");
    System.out.println("How are you?");
  }
}
    1. Save the file, then compile it using javac.
    javac Hello2.java
    1. Run the file from the command line by typing java Hello2.
    $ java Hello2
Hello, World!
How are you?
    1. Open the program in your editor and add two comments as follows.
    public class Hello2 {
  public static void main(String[] args) {
    System.out.println("Hello, World!"); //first line
    System.out.println("How are you?"); //second line
  }
}
    1. Save, compile, and run the program.

     

  2. Note that comments were not printed. Comments can go on either their own line or at the end of lines containing code.
    1. In a new file named Goodbye.java, create a new class named Goodbye.
    2. Create a new main method and add the following code.
    public class Goodbye {
  public static void main(String[] args){
    System.out.print("Goodbye, ");
    System.out.println("cruel world.");
  }
}
    1. Compile and run the program.
    $ javac Goodbye.java
$ java Goodbye
Goodbye, cruel world.

    Note that if you instead see the following output,

    $ java Goodbye
Goodbye, 
cruel world.

    you most likely typed

    System.out.println("Goodbye, ");

    rather than

    System.out.print("Goodbye, ");

    which erroneously added a newline to the statement.