这两行代码什么是什么意思int cursor=random.nextInt(a.length()); sb.append(a.charAt(cursor));

public class CollectionTest {

/**

* @param args

*/

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

public void testSort(){

String a="abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";

Random random=new Random();

//String s;

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

StringBuilder sb=new StringBuilder();

do{

sb.delete(0, sb.length());

int strlen=random.nextInt(10)+1;

//if(strlen==0)continue;

for(int k=0;k<=strlen;k++) {

int cursor=random.nextInt(a.length());

sb.append(a.charAt(cursor));

}

}while(stringList.contains(sb.toString()));

stringList.add(sb.toString());

}

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

for(String str:stringList) {

System.out.println("序列"+str);

}

Collections.sort(stringList);

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

for(String str:stringList) {

System.out.println("序列"+str);

}

}

public static void main(String[] args) {

// TODO Auto-generated method stub

CollectionTest ec=new CollectionTest();

ec.testSort();

}