| Expression | New String | Comment |
|---|---|---|
| String snake = "Rattlesnake"; | "Rattlesnake" | Create original String |
| snake.substring(0,6) | "Rattle" | Characters starting at character 0 to character 6-1 |
| snake.substring(0,11) | "Rattlesnake" | 0 to length includes all the characters of the original string |
| snake.substring(10, 11) | "e" | Character 10 is the last one |
| snake.substring(6,6) | "" | If beginIndex==endIndex, an empty substring is created. |
| snake.substring(5,3) | If beginIndex is greater than endIndex, an exception is thrown. | |
| snake.substring(5,12) | if endIndex is greater than length, an exception is thrown. |
String Objects
class BeautyShock
{
public static void main (String[] arg)
{
String line1 = "Only to the wanderer comes\n";
String line2 = "Ever new this shock of beauty\n";
String poem = line1 + line2;
System.out.print( poem );
}
}
Recall that
control characters are bit patterns
that indicate such things as the end of a line or page separations.
Other control characters represent the mechanical
activities of old communications equipment.
The characters that a String object contains can
include control characters.
Examine the program.
The sequence \n represents the control character
that ends a line.
This control character is embedded in the data of the strings.
The object referenced by poem has two of them.
The program writes to the monitor:
Only to the wanderer comes Ever new this shock of beauty
Although you do not see them in the output,
the control characters are part of the data in the String.
Here is another method from the String class:
public String toLowerCase();
This method
constructs a new String object containing all lower case letters.
There is also a method that produces a new String object
containing all upper case letters:
public String toUpperCase();
Here are some lines of code. Which ones are correct?