JavaSE（08）（List集合）

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测试vector类:package zz.itheima.list;import java.util.List;import java.util.Vector;public class TestVector {    //测试vector类    public static void main(String[] args) {        //Vector （向量列表）底层数据结构是动态数组，线程安全，增删和查询都很慢，出事容量为10，增量为10.        //是list结构的实现类        Vector v = new Vector();        //1.存储//      boolean add(Object o)   继承自Collection        v.add("hello");        v.add(100);//      boolean addAll(Collection c)   继承自Collection//      add (int index，Object o)在第几个位置添加什么数据        v.add(1, "world");        System.out.println(v);//      boolean addAll (int index，Collection c)        //2.替换//      set(int index，Object o)把下标为index的数据替换为后面新的数据        v.set(2, 200);        System.out.println(v);        //3.删除//      boolean remove(Object o)  继承自Collection        v.remove("world");        System.out.println(v);//      boolean removeAll(Collection c)  继承自Collection//      boolean retainAll(Collection c)  继承自Collection//      void clear()  继承自Collection        v.clear();        System.out.println(v);//      remove(int index)        v.add(0, "你好！");        System.out.println(v);        v.remove(0);        System.out.println(v);        //4.判断//      boolean contains(Object o)   继承自Collection        System.out.println(v.contains("asdf"));//      boolean containsAll(Collection c)  继承自Collection//      boolean isEmpty()   继承自Collection        System.out.println(v.isEmpty());//      int indexOf(Object o)数据的下标        System.out.println(v.indexOf("asdf"));//-1代表没有找到内容所以就没有所谓的下标//      int lastIndexOf(Object o)        //5.获取//      int size()   继承自Collection        v.add("这是增加用的测试数据");        System.out.println(v.size());        v.add("asdf");v.add("iop");v.add(new Dog());v.add("");v.add("");v.add("");v.add("");        System.out.println(v.capacity());//出事容量为10，增量为10//      Object get(int index)目前只能使用Object类进行接收，需要向下转型        for (int i = 0; i < v.size(); i++) {            Object temp = v.get(i);            System.out.println(temp);        }//      List subList(int fromIndex，int lastIndex) 固定开始和结尾的子集合        List vv = v.subList(1, 3);        System.out.println("*************************");        System.out.println(vv);        System.out.println(vv.getClass());//      Object[] toArray()    继承自Collection        Object[] o=v.toArray();    }}运行结果：[hello, world, 100][hello, world, 200][hello, 200][][你好！][]falsetrue-1110这是增加用的测试数据asdfiopzz.itheima.list.Dog@600c199f*************************[asdf, iop]class java.util.Collections$SynchronizedRandomAccessListArrayList 的测试类：package zz.itheima.list;import java.util.ArrayList;public class TestArrayList {    //ArrayList 的测试类（是List接口的实现类之一）存储一组允许重复、有序的对象    public static void main(String[] args) {        // 案例：现有一个存储了一组字符串的List，请去重(用两个集合)        ArrayList al = new ArrayList();        ArrayList newArray = new ArrayList();        al.add("aaa");        al.add("bbb");        al.add("aaa");        al.add("bbb");        al.add("eee");        for (int i = 0; i < al.size(); i++) {            //取数据            String temp = (String) al.get(i);            if (!newArray.contains(temp)) {                newArray.add(temp);            }        }        System.out.println(newArray);    }}运行结果：[aaa, bbb, eee]LinkedList的测试类：package zz.itheima.list;import java.util.ArrayList;import java.util.LinkedList;public class TestLinkedList {    //LinkedList的测试类    public static void main(String[] args) {        LinkedList linkedList = new LinkedList();        ArrayList arrayList = new ArrayList();        linkedList.add("abc");        linkedList.addFirst("def");        System.out.println(linkedList.get(0));        System.out.println(linkedList.getFirst());        //测试LinkedList和ArrayList的增删效率        long begin = System.currentTimeMillis();        for (int i = 0; i < 10000000; i++) {            linkedList.add(i);        }        long end = System.currentTimeMillis();        System.out.println("LinkedList用了："+(end-begin)+"毫秒的时间");//      long begin = System.currentTimeMillis();//      for (int i = 0; i < 10000000; i++) {//          arrayList.add(i);//      }//      long end = System.currentTimeMillis();//      System.out.println("LinkedList用了："+(end-begin)+"的时间");        //经测试，Arraylist 的插入数据要比LinkedList的效率要高    }}运行结果：defdef使用Vector增删改查package zz.itheima.list;import java.util.Vector;public class Demo1 {    public static void main(String[] args) {        //练习：使用Vector实现对图书(书名、价格)的增、删(根据书名)、遍历输出和单个查询(书名)        Vector bookVector = new Vector();        //增        bookVector.add(new Book("aaa", 100.9));        bookVector.add(new Book("bbb", 101.9));        bookVector.add(new Book("ccc", 102.9));        bookVector.add(new Book("ddd", 103.9));        bookVector.add(new Book("eee", 104.9));        bookVector.add(new Book("fff", 105.9));        System.out.println(bookVector);        //删        String keyName = "bbb";        for (int i = 0; i < bookVector.size(); i++) {            Book temp = (Book) bookVector.get(i);            if (temp.getName().equals(keyName)) {                bookVector.remove(i);                break;            }        }        System.out.println(bookVector);        //遍历输出        for (int i = 0; i < bookVector.size(); i++) {            Book temp = (Book) bookVector.get(i);            System.out.println(temp.getName());        }        //根据书名单个查询        boolean flag = true;        for (int i = 0; i < bookVector.size(); i++) {            Book temp = (Book) bookVector.get(i);            if (temp.getName().equals("aaa")) {                System.out.println("找到了");                flag = false;                break;            }        }        if (flag) {            System.out.println("没有找到！");        }    }}运行结果：[aaa:100.9, bbb:101.9, ccc:102.9, ddd:103.9, eee:104.9, fff:105.9][aaa:100.9, ccc:102.9, ddd:103.9, eee:104.9, fff:105.9]aaacccdddeeefff找到了集合去重：package zz.itheima.list;import java.util.ArrayList;public class Demo2 {    public static void main(String[] args) {        // 练习：现有一个存储了一组对象的List，请去重(注意重写equals方法)        ArrayList al=new ArrayList();        ArrayList newAL=new ArrayList();    //空集合        al.add(new Book("aaa", 10.08));        al.add(new Book("bbb", 10.08));        al.add(new Book("aaa", 10.08));        for (int i = 0; i < al.size(); i++) {            //1.取            //2.判断            //3.放还是不放            Book temp=(Book)al.get(i);            if(!newAL.contains(temp))                newAL.add(temp);        }        System.out.println(newAL);    }}运行结果：[aaa:10.08, bbb:10.08]TestContains的测试类：package zz.itheima.list;import java.util.ArrayList;import java.util.List;public class TestContains {    //TestContains的测试类    public static void main(String[] args) {        // contains的内部实现是通过equals方法判断是否存在的                // 自定义类中必须重写equals方法        List bookList = new ArrayList();        bookList.add(new Book("aaa",10.04));        bookList.add(new Book("bbb",10.04));        bookList.add(new Book("ccc",10.04));        boolean result = bookList.contains(new Book("aaa", 10.04));        System.out.println(result);    }}运行结果：truebean类：package zz.itheima.list;public class Dog {}package zz.itheima.list;public class Book {    private String name;    private double price;    public Book(String name, double price) {        super();        this.name = name;        this.price = price;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public double getPrice() {        return price;    }    public void setPrice(double price) {        this.price = price;    }    public String toString()    {        return name+":"+price;    }    public boolean equals(Object o){        if(this==o)            return true;        else {            if(o instanceof Book)            {                Book other=(Book)o;                if(this.getName().equals(other.getName())&&this.getPrice()==other.getPrice())                    return true;                else {                    return false;                }            }            else {                return false;            }        }    }}书管理类：package zz.itheima.list;import java.util.ArrayList;    /**     * 书的管理类     * @author Administrator     *     */public class BookMgr {    private ArrayList bookList ;    public BookMgr() {        bookList = new ArrayList();    }    //添加    public void addBook(String name,double price){        bookList.add(new Book(name, price));        System.out.println(bookList);        System.out.println("添加成功！");    }    //删除    public void delBook(String name){        boolean flag = true;        for (int i = 0; i < bookList.size(); i++) {            Book temp = (Book) bookList.get(i);            if (name.equals(temp.getName())) {                bookList.remove(i);                flag = false;                System.out.println("删除成功");                break;            }        }        if (flag) {            System.out.println("书不存在");        }        System.out.println(bookList);    }    //修改（根据名称修改价格）    public void editPrice(String name,double newPrice){        for (int i = 0; i < bookList.size(); i++) {            Book temp = (Book) bookList.get(i);            if (temp.getName().equals(name)) {                temp.setPrice(newPrice);            }        }        System.out.println("修改成功了");        System.out.println(bookList);    }}测试管理类：package zz.itheima.list;public class TestBookMgr {    public static void main(String[] args) {        BookMgr bm = new BookMgr();        bm.addBook("aaa", 100);        bm.addBook("bbb", 100);        bm.addBook("ccc", 100);        bm.addBook("ddd", 100);        bm.addBook("eee", 100);        bm.delBook("ddd");        bm.editPrice("aaa", 200);    }}运行结果：[aaa:100.0]添加成功！[aaa:100.0, bbb:100.0]添加成功！[aaa:100.0, bbb:100.0, ccc:100.0]添加成功！[aaa:100.0, bbb:100.0, ccc:100.0, ddd:100.0]添加成功！[aaa:100.0, bbb:100.0, ccc:100.0, ddd:100.0, eee:100.0]添加成功！删除成功[aaa:100.0, bbb:100.0, ccc:100.0, eee:100.0]修改成功了[aaa:200.0, bbb:100.0, ccc:100.0, eee:100.0]
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