【java】打印半菱形

package test;

public class tuxing {
	public static void main(String[] args) {
		int n=4;
		int i,j;
		for(i=1;i<=4;i++)
		{
			for(j=1;j<=2*i-1;j++) 
			{
				System.out.print("*");
			}
			for(j=1;j<=7-i;j++) 
			{
				System.out.print(" ");
			}
			System.out.println();
		}
		for(i=3;i>=1;i--)
		{
			for(j=1;j<=2*i-1;j++) 
			{
				System.out.print("*");
			}
			for(j=1;j<=7-i;j++) 
			{
				System.out.print(" ");
			}
			System.out.println();
		}
	}

}