建個包整個拷貝貼上就可以跑了
有不懂歡迎發問

import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Random;
import java.util.stream.Collectors;

public class itTest {
	public static void main(String[] args) {
		int[] data = new int[10];
		Random ran = new Random();
		for (int i = 0; i < data.length; i++) {
			data[i] = ran.nextInt(100) + 1;
		}
		BigData bigData = new BigData(data);
		System.out.println("before sort:" + bigData.toString());
		System.out.println(bigData.search(30));
		bigData.sort();
		System.out.println("after sort:" + bigData.toString());
        /**
            before sort:67,50,2,18,19,86,88,6,47,51
            false
            after sort:88,86,67,51,50,47,19,18,6,2
        */
    }

}

class BigData {
	private int[] number;

	public BigData(int[] sample) {
		this.number = sample;
	}

	public boolean search(int data) {
		return Arrays.binarySearch(this.number, data) >= 0;
	}

	public void sort() {
		Arrays.sort(this.number);
		for (int i = 0; i < number.length / 2; i++) {
			int temp = number[i];
			number[i] = number[number.length - i - 1];
			number[number.length - i - 1] = temp;
		}

	}

	public String toString() {
		return Arrays.stream(number).mapToObj(String::valueOf).collect(Collectors.joining(","));
	}
}

package demo;

import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Random;
import java.util.stream.Collectors;

public class itTest {
	public static void main(String[] args) {
		int[] data = new int[10];
		Random ran = new Random();
		for (int i = 0; i < data.length; i++) {
			data[i] = ran.nextInt(100) + 1;
		}
		BigData bigData = new BigData(data);
		System.out.println("before sort:" + bigData.toString());
		System.out.println(bigData.search(30));
		bigData.sort();
		System.out.println("after sort:" + bigData.toString());
	}

}

class BigData {
	private int[] number;

	public BigData(int[] sample) {
		this.number = sample;
	}

	public boolean search(int data) {
		boolean result = false;
		for (int i : number) {
			if (i == data) {
				result = true;
			}
		}
		return result;
	}

	public void sort() {
		int temp;
		for (int i = 0; i < number.length; i++) {
			for (int j = i + 1; j < number.length; j++) {
				if (number[i] < number[j]) {
					temp = number[i];
					number[i] = number[j];
					number[j] = temp; // 讓兩數交換位子
				}
			}
		}

	}

	public String toString() {
		String result = "";
		for (int i : number) {
			result += "," + i;
		}
		return result.substring(1);
	}
}