Java编程思想第四版(Holding Your Objects )----第11章自由练习(个人练习)
作者：互联网
自由练习、书中例子实例
package out.file;
/**
* @program: ChapterEleven
* @description:
* @author: Tenco_vivid
* @create: 2019-07-24 15:09
**/
import com.elevenexercise30.demo.pets.*;
import out.file.pets.Person;
import net.mindview.util.Null;
import org.w3c.dom.ls.LSInput;
import javax.naming.NamingEnumeration;
import java.sql.Array;
import java.util.*;
import static net.mindview.util.Print.*;
class A{
private static long count ;
//哦，对了static只能初始化一次
private final long id = count++;
public long getId(){
return id;
}
}
class B extends A{}
class C extends A{}
class D extends A{}
class F extends A{}
public class ex1 {
//--------------------为什么啊，为什么???????一定要这个位置-----------------------
static Collection fill(Collection<String> co3) {
co3.add("a");
co3.add("b");
co3.add("c");
return co3;
}
static Map fill(Map<String,String> ma1) {
ma1.put("a","A");
ma1.put("b","B");
ma1.put("c","C");
return ma1;
}
//------------------------------------------------
public static void display(Iterator<Pet> it){
while (it.hasNext()){
Pet pt = it.next();
print(pt.id()+" "+pt);
}
}
//------------------------------------------------
public static Map<Person,List<? extends Pet>> mp = new HashMap<Person,List<? extends Pet>>();
static {
mp.put(new Person("Dawn"),Arrays.asList(new Cymric(),new Mutt()));
}
//------------------------------------------------
public static void printQ(Queue qu1){
while (qu1.peek()!=null){
print(qu1.remove());
}
}
//@SuppressWarnings("unchecked")
public static void main(String[] args) {
ArrayList<A> al1 = new ArrayList<>();
for (int i=0; i<3; i++){
al1.add(new A());
}
for (int i=0; i<al1.size(); i++){
print(al1.get(i).getId());
}
for (A xa:al1) {
print(xa.getId());
}
print("----------------------------------------------------------");
ArrayList<A> al2 = new ArrayList<>();
al2.add(new B());
al2.add(new C());
al2.add(new D());
al2.add(new F());
for (A xa: al2) {
print(xa.getId());
}
print(al2);
print("----------------------------------------------------------");
Collection<Integer> co1 = new ArrayList<>();
for (int i = 0; i <10 ; i++) {
co1.add(i);
}
for (Integer xin:co1) {
print(xin);
}
print("----------------------------------------------------------");
Collection<Integer> co2 = new ArrayList<Integer>(Arrays.asList(1,2,3,4,5));
Integer[] xin = {6,7,8,9,10};
co2.addAll(Arrays.asList(xin));
print(co2+"one.");
Collections.addAll(co2,11,12,13,14,15);
print(co2+"two.");
Collections.addAll(co2,xin);
print(co2+"three.");
print("----------------------------------------------------------");
class A1{}
class B1 extends A1{}
class C1 extends A1{}
class D1 extends A1{}
class E1 extends B1{}
class F1 extends B1{}
List<A1> list1 = new ArrayList<A1>(Arrays.asList(new B1(), new C1(), new D1()));
print(list1);
List<A1> list2 = new ArrayList<A1>();
Collections.addAll(list2,new E1(),new F1());
print(list2);
List<A1> list3 = Arrays.<A1>asList(new E1(),new F1());
print(list3);
print("----------------------------------------------------------");
print(fill(new ArrayList<>()));
print(fill(new LinkedList<>()));
print(fill(new HashSet<>()));
print(fill(new TreeSet<>()));
print(fill(new LinkedHashSet<>()));
print(fill(new HashMap<>()));
print(fill(new TreeMap<>()));
print(fill(new LinkedHashMap<>()));
print("----------------------------------------------------------");
Random ra1 = new Random(19);
List<Pet> pets = Pets.arrayList(3);
print(pets);
Hamster h = new Hamster();
pets.add(h);
print(pets);
print(pets.contains(h));
pets.remove(h);
print(pets);
//
Pet pet1 = pets.get(1);
print(pets.indexOf(pet1));
Pet cy1 = new Cymric();
print(pets.indexOf(cy1));
pets.remove(cy1);
pets.remove(pet1);
print(pets);
//
pets.add(1,new Manx());
print(pets);
List<Pet> pet2 = pets.subList(0,2);
print(pet2);
print(pets.containsAll(pet2));
Collections.sort(pet2);
print(pet2);
//
print("go on !");
print(pets.containsAll(pet2));
Collections.shuffle(pet2);
print(pet2);
print(pets.containsAll(pet2));
//
List<Pet> pet3 = new ArrayList<Pet>(pets);
pet2 = Arrays.asList(pets.get(1),pets.get(2));
print(pet3);
print(pet3.containsAll(pet2));
print(pet2);
//
print("go on 2!");
pet3 = new ArrayList<Pet>(pets);
print(pet3);
pet3.removeAll(pet2);
print(pet3);
pet3.add(1,new Mouse());
print(pet3);
pet3.addAll(pet2);
print(pet3);
//
print(pets.isEmpty());
pets.clear();
print(pets.isEmpty());
pets.addAll(Pets.arrayList(4));
print(pets);
Object ob = pets.toArray();
print(ob);
Pet[] pet4 = pets.toArray(new Pet[0]);
print(pet4);
print(pet4[0].id());
print("----------------------------Iterator-1-----------------------------");
List<Pet> pets2 = Pets.arrayList(6);
Iterator<Pet> it = pets2.iterator();
//
while (it.hasNext()){
print(it.next());
}
//
for (Pet pt:pets2) {
print(pt);
}
//?????????why????what????为什么一定要这样赋值,是因为返回指定开头是么
it = pets2.iterator();
for (int i = 0; i < pets2.size(); i++) {
it.next();
//?"????
it.remove();
}
print(pets2);
print("----------------------------------------------------------");
ArrayList<Pet> al3 = Pets.arrayList(5);
LinkedList<Pet> ll3 = new LinkedList<>(al3);
HashSet<Pet> hs3 = new HashSet<>(al3);
TreeSet<Pet> tp3 = new TreeSet<>(al3);
display(al3.iterator());
display(ll3.iterator());
display(hs3.iterator());
display(tp3.iterator());
print("----------------------------------------------------------");
List<Pet> list = Pets.arrayList(5);
ListIterator<Pet> it2 = list.listIterator();
while (it2.hasNext()){
print(it2.next()+" "+it2.nextIndex());
}
//
while (it2.hasPrevious()){
print(it2.previous().id());
}
it2 = list.listIterator();
while (it2.hasNext()){
it2.next();
it2.set(Pets.randomPet());
}
print(list);
print("----------------------------------------------------------");
LinkedList<Pet> li2 = new LinkedList<Pet>(Pets.arrayList(5));
print(li2);
print(li2.getFirst());
print(li2.element());
print(li2.peek());
print(li2.getFirst());
//
print(li2.remove());
print(li2.removeFirst());
print(li2.poll());
print(li2);
//
li2.addFirst(new Rat());
print(li2);
li2.offer(Pets.randomPet());
print(li2);
li2.add(new Hamster());
print(li2);
print(li2.removeLast());
print("-----------------------------南风-----------------------------");
Stack<String> sk1 = new Stack<>();
for (String str:"xu li ya.".split(" ")) {
sk1.push(str);
if (sk1.isEmpty()){
print(sk1.pop());
}
}
print("----------------------------------------------------------");
Random ra2 = new Random(19);
SortedSet<Integer> ss1 = new TreeSet<>();
for (int i = 0; i < 100; i++) {
ss1.add(ra2.nextInt(10));
}
print(ss1);
print("----------------------------------------------------------");
Set<String> ss2 = new HashSet<>();
Collections.addAll(ss2,"a,b,c,d,e".split(" "));
print(ss2);
ss2.add("f");
print(ss2);
print(ss2.contains("f"));
print(ss2.contains("g"));
//
Set<String> ss3 = new HashSet<>();
Collections.addAll(ss3,"a,b,c".split(" "));
print(ss2.containsAll(ss3));
ss2.removeAll(ss3);
print(ss2);
ss3.removeAll(ss3);
print(ss3);
Set<String> ss4 = new HashSet<>();
Set<String> ss5 = new HashSet<>();
ss4.add("a");
ss4.add("b");
ss4.add("c");
ss5.add("a");
ss5.add("c");
ss5.add("b");
ss5.add("d");
ss5.add("e");
print(ss5.containsAll(ss4));
print("----------------------------------------------------------");
Map<Integer,Integer> mp1 = new HashMap<>();
Random ra3 = new Random(19);
for (int i = 0; i <1000 ; i++) {
int k = ra3.nextInt(10);
//靠，一定得是Integer
Integer v = mp1.get(k);
mp1.put(k,v == null ? 1 : (v+1));
}
print(mp1);
print("----------------------------------------------------------");
print(mp.keySet());
print(mp.values());
for (Person pe:mp.keySet()) {
print(pe);
for (Pet pe1:mp.get(pe)) {
print(pe1);
}
}
print("----------------------------------------------------------");
Queue<Integer> qu2 = new LinkedList<>();
Random ra4 = new Random(19);
for (int i = 0; i < 100; i++) {
qu2.offer(ra4.nextInt(i+10));
}
print(qu2);
Queue<Character> qu3 = new LinkedList<>();
for (Character ch:"nishigedabendanme".toCharArray()) {
qu3.offer(ch);
printQ(qu3);
}
print("----------------------------------------------------------");
print("----------------------------------------------------------");
print("----------------------------------------------------------");
print("----------------------------------------------------------");
print("----------------------------------------------------------");
print("----------------------------------------------------------");
}
}
标签：11,Java,li2,练习,add,pets,pet2,print,new 来源： https://blog.csdn.net/weixin_43378197/article/details/97424101