How to quickly print arrays?

[Charles Fox]

Is there some little utility function that will let me do
System.out.println(magicfunction(a))

where a is an array of doubles, ints, or bytes,
and it prints a nice pretty representation of the contents of a:

[ 1 , 2 , 3 , 4]

I've written a few of these myself but I dont want to reinvent the wheel here!

 

[Murray]

Is there some little utility function that will let me do
System.out.println(magicfunction(a))

where a is an array of doubles, ints, or bytes,
and it prints a nice pretty representation of the contents of a:

[ 1 , 2 , 3 , 4]

I've written a few of these myself but I dont want to reinvent the wheel

here!

I don't believe there's anything in the JDK, but you could try the Jakarta
Commons Lang package. It has a toString() method in ArrayUtils that handles
primitive and Object arrays (even multidimensional). The output looks like
{1,2,3,4} but if you need something more specific you can use
ToStringBuilder which is in the same package.

http://jakarta.apache.org/commons/lang/

 

[Chris Smith]

Is there some little utility function that will let me do
System.out.println(magicfunction(a))

where a is an array of doubles, ints, or bytes,
and it prints a nice pretty representation of the contents of a:

[ 1 , 2 , 3 , 4]

I've written a few of these myself but I dont want to reinvent the wheel here!

I'm not aware of such a thing offered as a third-party library. It's so
trivial that the challenge of deploying the library would dwarf writing
it yourself, so we're pretty much doomed to have people privately invent
their own copies until Sun sees fit to include this in the core API.
(Feel free to submit an RFE for this, by all means.)

--
www.designacourse.com
The Easiest Way to Train Anyone... Anywhere.

Chris Smith - Lead Software Developer/Technical Trainer
MindIQ Corporation

 

[Joona I Palaste]

Is there some little utility function that will let me do
System.out.println(magicfunction(a))

where a is an array of doubles, ints, or bytes,
and it prints a nice pretty representation of the contents of a:

[ 1 , 2 , 3 , 4]

I've written a few of these myself but I dont want to reinvent the wheel here!

What's wrong with System.out.println(Arrays.asList(a))?

 

[Murray]

here!

What's wrong with System.out.println(Arrays.asList(a))?

That doesn't work for primitive arrays

 

[Real Gagnon]

privately invent their own copies until Sun sees fit to include this
in the core API. (Feel free to submit an RFE for this, by all means.)

Actually, nice array printing is in 1.5 :

public class Test {
public static void main(String args[]) {
String s[] = {"a", "b", "c", "d"};
double[][] d = {
{0.50, 0.70, 0.40, 0.60},
{0.50, 1.10, 0.50, 0.80}
};
System.out.println(java.util.Arrays.toString(s));
System.out.println(java.util.Arrays.deepToString(d));
// output
// [a, b, c, d]
// [[0.5, 0.7, 0.4, 0.6], [0.5, 1.1, 0.5, 0.8]]
}
}

Bye.

 

[Chris Smith]

Actually, nice array printing is in 1.5 :

Good to hear it.

--
www.designacourse.com
The Easiest Way to Train Anyone... Anywhere.

Chris Smith - Lead Software Developer/Technical Trainer
MindIQ Corporation

 

[Joona I Palaste]

That doesn't work for primitive arrays

I didn't think of that. Thanks for the correction.

 

[Neal Gafter]

Is there some little utility function that will let me do
System.out.println(magicfunction(a))

where a is an array of doubles, ints, or bytes,
and it prints a nice pretty representation of the contents of a:

[ 1 , 2 , 3 , 4]

I've written a few of these myself but I dont want to reinvent the wheel here!

in JDK1.5, Arrays.toString(a)