public final class Util extends Object
A static class providing utility methods to all of JFace.
Modifier and Type | Field and Description |
---|---|
static SortedSet |
EMPTY_SORTED_SET
An unmodifiable, empty, sorted set.
|
static String |
ZERO_LENGTH_STRING
A common zero-length string.
|
Modifier and Type | Method and Description |
---|---|
static void |
assertInstance(Object object,
Class c)
Verifies that the given object is an instance of the given class.
|
static int |
compare(boolean left,
boolean right)
Compares two boolean values.
|
static int |
compare(Comparable[] left,
Comparable[] right)
Compares two arrays of comparable objects -- accounting for
null . |
static int |
compare(Comparable left,
Comparable right)
Compares to comparable objects -- defending against
null . |
static int |
compare(int left,
int right)
Compares two integer values.
|
static int |
compare(List left,
List right)
Compares two lists -- account for
null . |
static boolean |
endsWith(Object[] left,
Object[] right,
boolean equals)
Tests whether the first array ends with the second array.
|
static boolean |
equals(Object[] leftArray,
Object[] rightArray)
Tests whether two arrays of objects are equal to each other.
|
static boolean |
equals(Object left,
Object right)
Checks whether the two objects are
null -- allowing for
null . |
static int |
hashCode(int i)
Provides a hash code based on the given integer value.
|
static int |
hashCode(Object object)
Provides a hash code for the object -- defending against
null . |
static int |
hashCode(Object[] objects)
Computes the hash code for an array of objects, but with defense against
null . |
static boolean |
startsWith(Object[] left,
Object[] right,
boolean equals)
Checks whether the second array is a subsequence of the first array, and
that they share common starting elements.
|
static String |
toString(Object[] array)
Converts an array into a string representation that is suitable for
debugging.
|
static String |
translateString(ResourceBundle resourceBundle,
String key,
String defaultString)
Provides a translation of a particular key from the resource bundle.
|
public static final SortedSet EMPTY_SORTED_SET
null
.public static final String ZERO_LENGTH_STRING
NON-NLS
next to code fragments. It's also a bit clearer to read.public static final void assertInstance(Object object, Class c)
object
- The object to check; may be null
.c
- The class which the object should be; must not be
null
.public static final int compare(boolean left, boolean right)
false
is considered to be
"less than" true
.left
- The left value to compareright
- The right value to compare-1
if the left is false
and the
right is true
. 1
if the opposite
is true. If they are equal, then it returns 0
.public static final int compare(int left, int right)
left
- The left value to compareright
- The right value to compareleft - right
public static final int compare(Comparable left, Comparable right)
null
.left
- The left object to compare; may be null
.right
- The right object to compare; may be null
.null
is considered
to be the least possible value.public static final int compare(Comparable[] left, Comparable[] right)
null
.left
- The left array to be compared; may be null
.right
- The right array to be compared; may be null
.null
is considered
to be the least possible value. A shorter array is considered
less than a longer array.public static final int compare(List left, List right)
null
. The lists must
contain comparable objects.left
- The left list to compare; may be null
. This
list must only contain instances of Comparable
.right
- The right list to compare; may be null
. This
list must only contain instances of Comparable
.null
is considered
to be the least possible value. A shorter list is considered less
than a longer list.public static final boolean endsWith(Object[] left, Object[] right, boolean equals)
left
- The array to check (larger); may be null
.right
- The array that should be a subsequence (smaller); may be
null
.equals
- Whether the two array are allowed to be equal.true
if the second array is a subsequence of the
array list, and they share end elements.public static final boolean equals(Object left, Object right)
null
-- allowing for
null
.left
- The left object to compare; may be null
.right
- The right object to compare; may be null
.true
if the two objects are equivalent;
false
otherwise.public static final boolean equals(Object[] leftArray, Object[] rightArray)
null
, but their elements may be
null
.leftArray
- The left array to compare; may be null
, and
may be empty and may contain null
elements.rightArray
- The right array to compare; may be null
, and
may be empty and may contain null
elements.true
if the arrays are equal length and the
elements at the same position are equal; false
otherwise.public static final int hashCode(int i)
i
- The integer valuei
public static final int hashCode(Object object)
null
.object
- The object for which a hash code is required.object.hashCode
or 0
if
object
if null
.public static final int hashCode(Object[] objects)
null
.objects
- The array of objects for which a hash code is needed; may be
null
.objects
; or 0
if
objects
is null
.public static final boolean startsWith(Object[] left, Object[] right, boolean equals)
left
- The first array to compare (large); may be null
.right
- The second array to compare (small); may be null
.equals
- Whether it is allowed for the two arrays to be equivalent.true
if the first arrays starts with the second
list; false
otherwise.public static final String toString(Object[] array)
array
- The array to convert; may be null
.null
.public static final String translateString(ResourceBundle resourceBundle, String key, String defaultString)
resourceBundle
- The key to look up in the resource bundle; should not be
null
.key
- The key to look up in the resource bundle; should not be
null
.defaultString
- The value to return if the resource cannot be found; may be
null
.key
. If
the key cannot be found, then it is simply the
defaultString
.Guidelines for using Eclipse APIs. Copyright (c) IBM Corp. and others 2000, 2006. All rights reserved.