Java实例练习——java实现自动生成长度为10以内的随机字符串（可用于生成随机密码）

package sorttest;

import java.util.ArrayList;

import java.util.Collections;

import java.util.List;

import java.util.Random;

public class SortTest {

	public void sortString() {

		List<String> stringList = new ArrayList<String>();

		char[] charAndnum = "1234567890ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz".toCharArray();

		Random random = new Random(); //用于产生随机数

		for (int j = 0; j < 10; j++) {

			String string = new String();

			do{

				int sLength = random.nextInt(10);

				for(int i = 0;i<((sLength==0)?1:sLength);i++){

					string+= charAndnum[random.nextInt(51)];

				}

				}while(stringList.contains(string));

				stringList.add(string);

		}

		System.out.println("---------------排序前---------------");

		for (String str : stringList) {

			System.out.println("生成的字符串为："+str);

		}

		Collections.sort(stringList);

		System.out.println("---------------排序后---------------");

		for (String str : stringList) {

			System.out.println("生成的字符串为："+str);

		}

	}

	public static void main(String[] args) {

		// TODO Auto-generated method stub

	SortTest sTest = new SortTest();

	sTest.sortString();

	}

}

　　今天更新第二种实现方式：（更简短）

package oop;

import java.io.IOException;

import java.nio.CharBuffer;

import java.util.Random;

import java.util.Scanner;

public class PassWrodsCreater implements Readable {

    private static Random random = new Random(47);

    private static final char[] alls =

            "abcdefghijklmnopqrstuvwxyz0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ@#!$%*&/".toCharArray();

    // 生成字密码的数量

    private int count;

    // 生成密码长度

    private int length;

    public PassWrodsCreater(int count,int length) {

        this.count = count;

        this.length = length;

    }

    @Override

    public int read(CharBuffer cb) throws IOException {

        if(count-- == 0)

            return -1;

        for(int i = 0; i < length; i++){

            cb.append(alls[random.nextInt(alls.length)]);

        }

        cb.append(" ");

        return 0;

    }

    public static void main(String[] args) {

        Scanner sc = new Scanner(new PassWrodsCreater(3,9));

        while(sc.hasNext())

            System.out.println(sc.next());

    }

}