第一种

static class T implements Comparable<T>{

private String name;

private int count;

public T(String name, int count) {

super();

this.name = name;

this.count = count;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public int getCount() {

return count;

}

public void setCount(int count) {

this.count = count;

}

@Override

public String toString() {

return name+"_"+count;

}

@Override

public int compareTo(T o) {

if(this.count!=o.count)

return o.count - this.count;降序，后面的减前面的降序，前面的减后面的升序

return this.name.compareTo(o.name);前面的减后面的升序

}

}

 

第二种

public static TreeSet<T> sortStudent(){

TreeSet<T> ts = new TreeSet<T>(new Comparator<T>() {

@Override

public int compare(T o1, T o2) {

if(o1.getCount()!=o2.getCount())

return o2.getCount()-o1.getCount();后面的减前面的降序

return o2.getName().compareTo(o1.getName());后面的减前面的降序，前面的见后面的升序

}

});