package FileRead; import javax.persistence.criteria.CriteriaBuilder; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.util.*; class name{ String name=new String(); int num=0; } public class FileRead { public static void main(String[] args) { try { FileInputStream fs=new FileInputStream("E:\\1.txt"); Scanner sc= new Scanner(fs); int num=0; HashMap<String,Integer> ts=new HashMap<String, Integer>(); LinkedList<name> list =new LinkedList<name>(); while (sc.hasNext()){ String s=sc.next(); if(ts.containsKey(s)){ Integer i=ts.get(s)+1; ts.put(s,i); } else { ts.put(s,1); } num++; } System.out.println("开始排序....."); int i=0; int [] nums=new int[num]; Set<String> keys=ts.keySet(); for(String key:keys){ nums[i]=ts.get(key); name n1=new name(); n1.num=nums[i]; n1.name=key; list.add(n1); } Collections.sort(list, new Comparator<name>() { @Override public int compare(name o1, name o2) { if(o1.num<o2.num){ return 1; } else if(o1.num==o2.num){ return 0; } return -1; } }); for(name n1:list){ System.out.println(n1.num+":"+n1.name); } } catch (FileNotFoundException e) { e.printStackTrace(); } } }
整体思想就是先把文件中的数据全部读出来后,存入一个map中。然后对已经存在的他的出现次数+1,然后接着put进去map中。 最后创建一个链表,里面存储name对象。然后对list进行排序,根据Collections.sort(list,new Coparator<name>(){
public int compare(name n1,name n2){
if(n1.num<n2.num){
return 1;
}else(n1.num==n2.num){
return 0;
}
return -1;
}
})