Exercise: Store 5 animal objects in a collection and traverse the animal objects.
Analysis:
A: Creating Animal classes
A: Non-parametric construction method
B: A method of constructing a parameter
C:get, set method
B: Create a Collection Object
A:collection animal = new Arrarylist ();
C: Create Animal objects
B:5 species of animals, feel free to think
D: Add animal objects into the collection
C: Add into the animal
E: Convert set to Array
D:object[] ToArray (): Sets the set to the array, you can implement the collection of traversal
F: Traversing an array
Animal type:
1 PackageZl_objecttest1;2 3 Public classAnimal {4 5 PrivateString name;6 PrivateString Color;7 Private intAge ;8 9 Ten PublicAnimal () { One Super(); A - } - the - - - PublicAnimal (string name, string color,intAge ) { + Super(); - This. Name =name; +Color =color; A This. Age =Age ; at } - - - - - PublicString GetName () { in returnname; - } to Public voidsetName (String name) { + This. Name =name; - } the PublicString GetColor () { * returnColor; $ }Panax Notoginseng Public voidsetcolor (String color) { -Color =color; the } + Public intGetage () { A returnAge ; the } + Public voidSetage (intAge ) { - This. Age =Age ; $ } $ - - the - PublicString toString () {Wuyi return"Animal [name=" + name + ", color=" + Color + ", age=" + Age the+ "]"; - } Wu}
Implementation class:
1 PackageZl_objecttest1;2 3 Importjava.util.ArrayList;4 Importjava.util.Collection;5 6 7 Public classanimalcollection {8 9 Public Static voidMain (string[] args) {Ten One //To create a collection object ACollection animal =NewArrayList (); - - //To create a collection object theAnimal A1 =NewAnimal ("Cat", "Tiger pattern", 2); -Animal A2 =NewAnimal ("Dutch Pig", "Pink", 1); -Animal A3 =NewAnimal ("Eagle", "Black and White", 4); -Animal A4 =NewAnimal ("Parrot", "Colorful", 2); +Animal A5 =NewAnimal ("Police dog", "Black", 3); - + //Add animal objects to the collection A //Animal.add (A1); Here is an upward transformation of Object ABJ = "A1"; at Animal.add (A2); - Animal.add (A3); - Animal.add (A4); - Animal.add (A5); - - //convert a collection to an array in //object[] ToArray (): Sets the set to the array, you can implement the collection of traversal - toobject[] ABJ =Animal.toarray (); + - //iterating through an array the for(intx = 0; x < abj.length; X + +) { * //System.out.println (abj[x]);//This prints out the address value. $ Panax Notoginseng //to make a sub-downward transition, you can call the method inside the animal -Animal s =(Animal) abj[x]; theSystem.out.println (s);//This calls the animal inside the Tostrin () + //call the format you want to display yourself ASystem.out.println ("kind:" + s.getname () + "\ T color:" +S.getcolor () the+ "\ t Age:" +s.getage ()); + } - $ } $ -}
Walk-through exercises for the Java 15-3 Collection