目录

481-Arrays排序源码解读

483-Arrays模拟排序

484-Arrays其他方法

485-Arrays课堂练习

---

481-Arrays排序源码解读

接口编程-compare

483-Arrays模拟排序

484-Arrays其他方法

二分搜索查找要求有序，如果数组中不存在这个元素，返回-（low+1）

使用int就是0，Integer就会是null

如果拷贝长度<0就抛出异常NegativeArraySizeException

485-Arrays课堂练习

package chapter13.arrays;

import java.util.Arrays;
import java.util.Comparator;

/**
 * @author LuHan
 * @version 1.0
 */
public class ArraysExcercise {
    public static void main(String[] args) {
        Book[] books = new Book[4];
        books[0]= new Book("红楼梦~", 100);
        books[1]= new Book("金瓶梅~",90);
        books[2] = new Book("青年文摘", 5);
        books[3]= new Book("java从入门到放弃", 300);
        Arrays.sort(books, new Comparator() {
            @Override
            public int compare(Object o1, Object o2) {
                Book book1=(Book) o1;
                Book book2=(Book) o2;
                double priceVal= book2.getPrice()-book1.getPrice();
                if(priceVal>0){
                    return 1;
                }else if(priceVal<0){
                    return -1;
                }else {
                    return 0;
                }
            }
        });
        System.out.println(Arrays.toString(books));
    }
}
class Book{
    private String name;
    private double price;

    public Book(String name, double price) {
        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;
    }

    @Override
    public String toString() {
        return "Book{" +
                "name='" + name + '\'' +
                ", price=" + price +
                '}';
    }
}