format()

[Mohammed shareef]

Can you help me in understanding the code on page No 491 Chapter 6 in Kathy Siera& Bert Bates ,please focus on 7d specially ,d is for integer but what 7 is for?

[marc weber]

Welcome to JavaRanch!

If you post some of the code, more people would be able to help.

[Mohammed shareef]

here is the code
int i1= -123;
int i2= 12345;
System.out.println(">%1$(7d< \n",i1);
System.out.println(">%0,7d <\n",i2);
System.out.println(">%+-7d< \n",i2);
System.out.println(">%2$b + %1$5d< \n",i1,false);
This produces output :
>(123)<
>012,345<
>+12345<
>false + -123<
In above code i can understand everything except the digit 7,what is the reason for putting 7 in first three line& 5 in the last line.can any one explain it? Thanking you in advance.

[marc weber]

According to the API for java.util.Formatter...

The format specifiers for general, character, and numeric types have the following syntax:

%[argument_index$][flags][width][.precision]conversion

So in the above examples, the 7 and the 5 specify width, which can be seen in this formatted output (using printf instead of println)...

>  (123)<
>012,345 <
>+12345 <
>false +  -123<

Try increasing these numbers, and see how the output is affected.