输出三角形 （java）

import java.util.Scanner;
public class a3 {
    public static void main(String[] args){
        Scanner sc = new Scanner(System.in);
        int key = sc.nextInt();
        sc.close();
        for (int i = 0; i < key; i++) {
            for(int j = 0; j <= i; j++) {
                System.out.print("*");
            }       
            System.out.println();
        }
        System.out.println("----------------------------");
        for (int i = 0; i < key; i++) {
            for(int j = 0; j < i; j++) {
                System.out.print(" ");
            } 
            for (int j = key - i; j > 0; j--) {
                System.out.print("*");
            }      
            System.out.println();
        }
        System.out.println("----------------------------");
        for (int i = 0; i < key; i++) {
            for(int j = key - i; j > 0; j--) {
                System.out.print("*");
            } 
            System.out.println();
        }
        System.out.println("----------------------------");
        for (int i = 1; i <= key; i++) {
            for(int j = key - i; j > 0; j--) {
                System.out.print(" ");
            } 
            for (int j = 0; j < i; j++) {
                System.out.print("*");
            }
            System.out.println();
        } 
    }
}