菱形是拼接的
public static void main(String[] args) {
    //平行四边形
    for(int i = 1;i <= 4;i++){
        for(int j = 1;j <= 4 - i;j++){
            System.out.print(" ");
        }
            System.out.print("****");
        System.out.println();

    }
    //等腰三角形
    System.out.println();
    System.out.println();
    for(int i = 1;i <= 4;i++){
        for(int j = 1;j <= 4 - i;j++){
            System.out.print(" ");
        }
        for(int k = 1;k <= 2 * i - 1;k++){
            System.out.print("*");
        }
        System.out.println();
    }
    //菱形
    System.out.println();
    System.out.println();
    for(int i = 1;i <= 4;i++){
        for(int j = 1;j <= 4 - i;j++){
            System.out.print(" ");
        }
        for(int k = 1;k <= 2 * i - 1;k++){
            System.out.print("*");
        }
        System.out.println();
    }
    for(int i = 3;i >= 1;i--){
        for(int j = 3;j >= i;j--){
            System.out.print(" ");
        }
        for(int k = 1;k <= 2 * i - 1;k++){
            System.out.print("*");
        }
            System.out.println();
    }
}