package java2;
import org.junit.Test;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Date;
public class CollectionTest {
@Test
public void test1(){
Collection coll=new ArrayList();
coll.add("AA");
coll.add("BB");
coll.add(123);
coll.add(new Date());
System.out.println(coll.size());
Collection coll1=new ArrayList();
coll1.add(456);
coll1.add("CC");
coll.addAll(coll1);
System.out.println(coll.size());
System.out.println(coll);
coll.clear();
System.out.println(coll.isEmpty());
}
}
package java0;
import org.junit.Test;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.List;
public class CollectionTest {
@Test
public void test1(){
Collection coll=new ArrayList();
coll.add(123);
coll.add(456);
coll.add(new Person("Jerry",20));
coll.add(new String("Tom"));
coll.add(false);
boolean contains=coll.contains(123);
System.out.println(contains);
System.out.println(coll.contains(new String("Tom")));
System.out.println(coll.contains(new Person("Jerry",20)));
Collection coll1= Arrays.asList(123,456);
System.out.println(coll.containsAll(coll1));
}
@Test
public void test2(){
Collection coll=new ArrayList();
coll.add(123);
coll.add(456);
coll.add(new Person("Jerry",20));
coll.add(new String("Tom"));
coll.add(false);
coll.remove(123);
System.out.println(coll);
coll.remove(new Person("Jerry",20));
System.out.println(coll);
Collection coll1=Arrays.asList(123,456);
coll.removeAll(coll1);
System.out.println(coll);
}
@Test
public void test3(){
Collection coll=new ArrayList();
coll.add(123);
coll.add(456);
coll.add(new Person("Jerry",20));
coll.add(new String("Tom"));
coll.add(false);
Collection coll1=Arrays.asList(123,456,789);
coll.retainAll(coll1);
System.out.println(coll);
Collection coll2=new ArrayList();
coll2.add(123);
coll2.add(456);
coll2.add(new Person("Jerry",20));
coll2.add(new String("Tom"));
coll2.add(false);
System.out.println(coll);
System.out.println(coll2);
System.out.println(coll.equals(coll2));
}
@Test
public void test4(){
Collection coll=new ArrayList();
coll.add(123);
coll.add(456);
coll.add(new Person("Jerry",20));
coll.add(new String("Tom"));
coll.add(false);
System.out.println(coll.hashCode());
Object[] arr=coll.toArray();
for (int i = 0; i < arr.length; i++) {
System.out.println(arr[i]);
}
List list=Arrays.asList(new String[]{"AA","BB","CC"});
System.out.println(list);
List list1=Arrays.asList(123,456);
System.out.println(list1.size());
System.out.println(list1);
List list2=Arrays.asList(new Integer[]{123,456});
System.out.println(list2.size());
System.out.println(list2);
}
}
package java0;
import org.junit.Test;
import javax.swing.text.html.HTMLDocument;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
public class IteratorTesst {
@Test
public void test1(){
Collection coll=new ArrayList();
coll.add(123);
coll.add(456);
coll.add(new Person("Jerry",20));
coll.add(new String("Tom"));
coll.add(false);
Iterator iterator=coll.iterator();
while(iterator.hasNext()){
System.out.println(iterator.next());
}
}
@Test
public void test2(){
Collection coll=new ArrayList();
coll.add(123);
coll.add(456);
coll.add(new Person("Jerry",20));
coll.add(new String("Tom"));
coll.add(false);
Iterator iterator=coll.iterator();
while(iterator.hasNext()){
Object obj=iterator.next();
if("Tom".equals(obj)){
iterator.remove();
}
}
iterator=coll.iterator();
while(iterator.hasNext()){
System.out.println(iterator.next());
}
}
}
package java0;
import org.junit.Test;
import java.util.ArrayList;
import java.util.Collection;
public class ForTest {
@Test
public void test1(){
Collection coll=new ArrayList();
coll.add(123);
coll.add(456);
coll.add(new Person("Jerry",20));
coll.add(new String("Tom"));
coll.add(false);
for(Object obj:coll){
System.out.println(obj);
}
}
@Test
public void test2(){
int[] arr=new int[]{1,2,3,4,55,6};
for(int i:arr){
System.out.println(i);
}
}
@Test
public void test3(){
String[] arr=new String[]{"MM","MM","MM"};
for(String s:arr){
s="GG";
}
for(String s:arr){
System.out.println(s);
}
}
}
package java0;
import jdk.management.resource.internal.inst.SocketOutputStreamRMHooks;
import org.junit.Test;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class ListTest {
@Test
public void test2(){
ArrayList list = new ArrayList();
list.add(123);
list.add(456);
list.add("AA");
list.add(456);
int index=list.indexOf(4567);
System.out.println(index);
System.out.println(list.lastIndexOf(123));
System.out.println(list);
Object obj=list.remove(2);
System.out.println(obj);
System.out.println(list);
list.set(1,"CC");
System.out.println(list);
list.add(114514);
System.out.println(list);
List sublist=list.subList(2,4);
System.out.println(sublist);
System.out.println(list);
}
@Test
public void test1(){
ArrayList list=new ArrayList();
list.add(123);
list.add(456);
list.add("AA");
list.add(456);
System.out.println(list);
list.add(1,"BB");
System.out.println(list);
List list1= Arrays.asList(1,2,3);
list.addAll(list1);
System.out.println(list);
System.out.println(list.get(0));
}
}
package java1;
import org.junit.Test;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.Set;
public class SetTest {
@Test
public void test1(){
Set set=new HashSet();
set.add(456);
set.add(123);
set.add(123);
set.add("AA");
set.add("CC");
set.add(1200);
Iterator iterator=set.iterator();
while(iterator.hasNext()){
System.out.println(iterator.next());
}
}
@Test
public void test2(){
Set set=new LinkedHashSet();
set.add(456);
set.add(123);
set.add(123);
set.add("AA");
set.add("CC");
set.add(129);
Iterator iterator=set.iterator();
while(iterator.hasNext()){
System.out.println(iterator.next());
}
}
}
package java1;
import org.junit.Test;
import java.util.Comparator;
import java.util.Iterator;
import java.util.TreeSet;
public class TreeSetTest {
@Test
public void test1(){
TreeSet set=new TreeSet();
set.add(new User("Tom",12));
set.add(new User("Jerry",32));
set.add(new User("Jim",2));
set.add(new User("Mike",65));
set.add(new User("Jack",33));
set.add(new User("Jack",56));
Iterator iterator=set.iterator();
while (iterator.hasNext()){
System.out.println(iterator.next());
}
}
@Test
public void test2(){
Comparator com=new Comparator() {
@Override
public int compare(Object o1, Object o2) {
if(o1 instanceof User && o2 instanceof User){
User u1=(User)o1;
User u2=(User)o2;
return Integer.compare(u1.getAge(),u2.getAge());
}else{
throw new RuntimeException("输入的数据类型不匹配");
}
}
};
TreeSet set = new TreeSet(com);
set.add(new User("Tom",12));
set.add(new User("Jerry",32));
set.add(new User("Jim",2));
set.add(new User("Mike",65));
set.add(new User("Mary",33));
set.add(new User("Jack",33));
set.add(new User("Jack",56));
Iterator iterator=set.iterator();
while (iterator.hasNext()){
System.out.println(iterator.next());
}
}
}
package java1;
public class User implements Comparable{
private String name;
private int age;
public User() {
}
public User(String name, int age) {
this.name = name;
this.age = age;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "User{" +
"name='" + name + '\'' +
", age=" + age +
'}';
}
@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
User user = (User) o;
if (age != user.age) return false;
return name != null ? name.equals(user.name) : user.name == null;
}
@Override
public int hashCode() {
int result = name != null ? name.hashCode() : 0;
result = 31 * result + age;
return result;
}
@Override
public int compareTo(Object o) {
if(o instanceof User){
User user=(User)o;
int compare=this.name.compareTo(user.name);
if(compare!=0){
return compare;
}else{
return Integer.compare(this.age,user.age);
}
}else{
throw new RuntimeException("输入的类型不匹配");
}
}
}
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