1、通过数组内容获取想要数组中几个唯一数据
@Test
public void t74() {
String[] arrStr = {"2092314", "2092313", "2078103", "588506", "353867", "337220", "337221", "337233", "337189", "318945"};
HashSet getrunmber = getrunmber(1, arrStr);
getrunmber.forEach(m -> Log.info(m));
}
/**
* 根据数组长，返回唯一相应数据
* @param n
* @param str
* @return
*/
public HashSet getrunmber(int n, String[] str) {
Random random = new Random();
HashSet setlist = new HashSet<>();
if (n <= str.length && n != 0 && str.length != 0 && str != null) {
while (setlist.size() < n) {
int c = random.nextInt(str.length);
setlist.add(str[c]);
}
} else {
Log.info("获取的数据大于String数据的长度");
return null;
}
return setlist;
}
2通过文件读取获取指定唯一数据
/**
* 通过读取文件或指定唯一数据
* @param n
* @param str
* @return
*/
public HashSet getrunmber(int n, String str) {
Random random = new Random();
HashSet setlist = new HashSet<>();
ArrayList list = fileReaderr(str);
if (n <= list.size() && n != 0 && list.size() != 0 && str != null) {
while (setlist.size() < n) {
int c = random.nextInt(list.size());
setlist.add(list.get(n));
}
} else {
Log.info("获取的数据大于String数据的长度");
return null;
}
return setlist;
}
/**
* 通过读取文件内容
* @param file
* @return list
*/
public static ArrayList fileReaderr(String file) {
BufferedReader bufferedReader = null;
String len = null;
ArrayList list = new ArrayList<>();
File numberpath = new File(file);
if (!numberpath.exists()) {
Log.info("文件不存在");
return null;
}
try {
bufferedReader = new BufferedReader(new FileReader(numberpath));
while ((len = bufferedReader.readLine()) != null) {
list.add(len);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (bufferedReader != null) {
try {
bufferedReader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
return list;
}
当前题目：通过数组获取唯一指定几个数据
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