Added section on interfaces. Added array info

This commit is contained in:
U-Christopher-PC\Christopher 2014-02-10 14:28:54 -07:00
parent 72ae07dd15
commit 928e53a108

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@ -101,14 +101,17 @@ public class LearnJava {
// Arrays
//The array size must be decided upon instantiation
//The format for declaring an array is follows:
//The following formats work for declaring an arrow
//<datatype> [] <var name> = new <datatype>[<array size>];
//<datetype> <var name>[] = new <datatype>[<array size>];
int [] intArray = new int[10];
String [] stringArray = new String[1];
boolean [] booleanArray = new boolean[100];
boolean boolArray [] = new boolean[100];
// Another way to declare & initialize an array
int [] y = {9000, 1000, 1337};
String names [] = {"Bob", "John", "Fred", "Juan Pedro"};
boolean bools[] = new boolean[] {true, false, false};
// Indexing an array - Accessing an element
System.out.println("intArray @ 0: " + intArray[0]);
@ -405,6 +408,46 @@ class PennyFarthing extends Bicycle {
}
//Interfaces
//Interface declaration syntax
//<access-level> interface <interface-name> extends <super-interfaces> {
// //Constants
// //Method declarations
//}
//Example - Food:
public interface Edible {
public void eat(); //Any class that implements this interface, must implement this method
}
public interface Digestible {
public void digest();
}
//We can now create a class that implements both of these interfaces
public class Fruit implements Edible, Digestible {
public void eat() {
//...
}
public void digest() {
//...
}
}
//In java, you can extend only one class, but you can implement many interfaces.
//For example:
public class ExampleClass extends ExampleClassParent implements InterfaceOne, InterfaceTwo {
public void InterfaceOneMethod() {
}
public void InterfaceTwoMethod() {
}
}
```
## Further Reading