Possible Duplicate:
Difference between int[] array and int array[]
Is there a difference between
int[] array = new int[10];
and
int array[] = new int[10];
?
Both do work, and the result is exactly the same. Which one is quicker or better? Is there a style guide which recommends one?
Both are equivalent. Take a look at the following:
int[] array;
// is equivalent to
int array[];
int var, array[];
// is equivalent to
int var;
int[] array;
int[] array1, array2[];
// is equivalent to
int[] array1;
int[][] array2;
public static int[] getArray()
{
// ..
}
// is equivalent to
public static int getArray()[]
{
// ..
}
They are both basically same, there is no difference in performance of any sort, the recommended one however is the first case as it is more readable.
int[] array = new int[10];
FROM JLS:
The [] may appear as part of the type at the beginning of the declaration, or as part of the declarator for a particular variable, or both.
From JLS http://docs.oracle.com/javase/specs/jls/se5.0/html/arrays.html#10.2
Here are examples of declarations of array variables that do not create arrays:
int[ ] ai; // array of int
short[ ][ ] as; // array of array of short
Object[ ] ao, // array of Object
otherAo; // array of Object
Collection<?>[ ] ca; // array of Collection of unknown type
short s, // scalar short
aas[ ][ ]; // array of array of short
Here are some examples of declarations of array variables that create array objects:
Exception ae[ ] = new Exception[3];
Object aao[ ][ ] = new Exception[2][3];
int[ ] factorial = { 1, 1, 2, 6, 24, 120, 720, 5040 };
char ac[ ] = { 'n', 'o', 't', ' ', 'a', ' ',
'S', 't', 'r', 'i', 'n', 'g' };
String[ ] aas = { "array", "of", "String", };
The [ ] may appear as part of the type at the beginning of the declaration, or as part of the declarator for a particular variable, or both, as in this example:
byte[ ] rowvector, colvector, matrix[ ];
This declaration is equivalent to:
byte rowvector[ ], colvector[ ], matrix[ ][ ];
Both are the same.
I usually use int[] array = new int[10];
, because of better (contiguous) readability of the type int[]
.
No, there is no difference. But I prefer using int[] array
as it is more readable.
There is no difference between these two declarations, and both have the same performance.
There is virtually no difference.
In both examples, you are assigning a new int[10]
to a reference variable.
Assigning to a reference variable either way will be equal in performance.
int[] array = new int[10];
The notation above is considered best practice for readability.
Cheers
来源:https://stackoverflow.com/questions/14559749/java-int-array-vs-int-array