Editing JavaLanguage (section)

==Arrays==
Array enthalten entweder:
*basic types
*object references
*array references.
Für alle Typen wird bei der Konstruktion der Defaultwert des Datentyps (null bei objects) eingesetzt. Arrays are declared by
 
 int[]   Array1;
 int     Array[];

and constructed by 
 int[] Array1;
 Array1 = new int[x];
 int[] Array2 = new int[n];
 char[] Array3 = {'\u0031','\u0033'};
 int[] primes;
 primes = new int[]{ 2, 5, 7, 11, 13 };

wobei n vom basic type byte, short oder int sein muß - long geht nicht. Arrays have the standard property length which can be used through
 
 if (Array2.length > 1)
 {
   ...
 }

 int[] numbers = {1,2,3,4,5,6,7,8,9,10};
 for (int item : numbers) {
   System.out.println("Count is: " + item);
 }

Creating an array of objects only allocates storage for object references, not the object themselves. Elements are initialized to their default value which is 0, 0.0, false or null.

If you pass an array to an method you would declare the method like this
 
 <return type> <method name>'''('''<type>[(<Space>)*]'''[]'''[(<Space>)*]<parameter name>''')''' 
 
In this case you don’t have to call new. Another initialization is 
 
 <Method>'''( new''' <Type>'''[] {''' <Element1>''',''' ...''',''' <ElementN> '''} );'''
 
An java array remembers the type of elements. Java arrays are '''0-based'''.

Arrays can be cast to Object and Clonable, but not to String. Die Klasse '''java.util.Arrays''' definiert nützliche Funktionen im Umgang mit Arrays.

If an array is created you cannot change its size. If you need to change the size at runtime and you only want to store subclasses of object you should use the class vector. Der Nachteil von vectors ist, dass es kein typisierter Speicher ist sondern alle Objekt-Subclasses speichert. Dies führt leicht zu Fehlern. Beim Auslesen aus einem vector muss man immer casten.