Java输出空心菱形

public static void Test3()
{
for (int i=0;i<=3 ;i++ )
{
for (int j=0;j<=7 ;j++ )
{
if (j==4-i||j==4+i)
{
System.out.print("*");
}
else
{
System.out.print(" ");
}
}
System.out.println();
}
for (int i=2;i>=0 ;i-- )
{
for (int j=0;j<=7 ;j++ )
{
if (j==4-i||j==4+i)
{
System.out.print("*");
}
else
{
System.out.print(" ");
}
}
System.out.println();
}
}