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public static void main(String[] args) throws Exception {
//读
BufferedReader du = new BufferedReader(new InputStreamReader(new FileInputStream(“D://filetest.txt”)));
//写
BufferedWriter xie = new BufferedWriter(new OutputStreamWriter(new FileOutputStream("D://filetest.txt")));
//对字符串操作 用StringBuffer
//创建StringBuffer 对象
StringBuffer stringBuffer = new StringBuffer();
//定义一个变量 用来判断是否和获取到的内容一致
String stringname = null;
//写到指定文件
for (int i = 0 ; i <5000; i++){
int num = (int) (Math.random()*10000);
xie.write(String.valueOf(num)+",");
}
//判断 如果指定文件的内容不为空 就放到StringBuffer 里进行操作
while((stringname=du.readLine())!=null){
stringBuffer.append(stringname+",");
}
//到上面一步已经获取到文件内容放到StringBuffer中
//然后开始对缓存区的内容进行分割split
//分割好以后就可以对内容进行排序 查询 等
String[] split = stringBuffer.toString().split(",");
//把分割好的字符串放到List集合中
MyArrayList<Integer> list = new MyArrayList<Integer>();
for (int i = 0;i<split.length;i++){
//因为分割好以后的数据都是String类型的所以在这里转换下类型
//Integer.parseInt
list.add(Integer.parseInt(split[i]));
}
int min =(int) list.get(0);
int max= (int)list.get(0);
for (int i = 0 ;i <list.size(); i++){
if(min>(int)list.get(i)){
min=(int)list.get(i);
}
if(max<(int)list.get(i)){
max=(int)list.get(i);
}
}
System.out.println("当前最大值为"+max+"最小值为:"+min);
for(int i = 0;i<list.size();i++){
System.out.println(list.get(i));
}
xie.flush();
xie.close();
}