java.lang.Object | |
↳ | org.apache.commons.collections.MapUtils |
Provides utility methods and decorators for Map and SortedMap instances.
It contains various type safe methods as well as other useful features like deep copying.
It also provides the following decorators:
fixedSizeMap(Map)
fixedSizeSortedMap(SortedMap)
lazyMap(Map, Factory)
lazyMap(Map, Transformer)
lazySortedMap(SortedMap, Factory)
lazySortedMap(SortedMap, Transformer)
predicatedMap(Map, Predicate, Predicate)
predicatedSortedMap(SortedMap, Predicate, Predicate)
transformedMap(Map, Transformer, Transformer)
transformedSortedMap(SortedMap, Transformer, Transformer)
typedMap(Map, Class, Class)
typedSortedMap(SortedMap, Class, Class)
multiValueMap(Map)
multiValueMap(Map, Class)
multiValueMap(Map, Factory)
Fields | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
EMPTY_MAP | An empty unmodifiable map. | ||||||||||
EMPTY_SORTED_MAP | An empty unmodifiable sorted map. |
Public Constructors | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
MapUtils should not normally be instantiated. |
Public Methods | |||||||||||
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Prints the given map with nice line breaks.
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Returns a fixed-sized map backed by the given map.
| |||||||||||
Returns a fixed-sized sorted map backed by the given sorted map.
| |||||||||||
Looks up the given key in the given map, converting the result into
a boolean, using the default value if the the conversion fails.
| |||||||||||
Gets a Boolean from a Map in a null-safe manner.
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Gets a boolean from a Map in a null-safe manner,
using the default value if the the conversion fails.
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Gets a boolean from a Map in a null-safe manner.
| |||||||||||
Gets a Byte from a Map in a null-safe manner.
| |||||||||||
Looks up the given key in the given map, converting the result into
a byte, using the default value if the the conversion fails.
| |||||||||||
Gets a byte from a Map in a null-safe manner.
| |||||||||||
Gets a byte from a Map in a null-safe manner,
using the default value if the the conversion fails.
| |||||||||||
Gets a Double from a Map in a null-safe manner.
| |||||||||||
Looks up the given key in the given map, converting the result into
a double, using the default value if the the conversion fails.
| |||||||||||
Gets a double from a Map in a null-safe manner.
| |||||||||||
Gets a double from a Map in a null-safe manner,
using the default value if the the conversion fails.
| |||||||||||
Gets a Float from a Map in a null-safe manner.
| |||||||||||
Looks up the given key in the given map, converting the result into
a float, using the default value if the the conversion fails.
| |||||||||||
Gets a float from a Map in a null-safe manner,
using the default value if the the conversion fails.
| |||||||||||
Gets a float from a Map in a null-safe manner.
| |||||||||||
Gets an int from a Map in a null-safe manner.
| |||||||||||
Gets an int from a Map in a null-safe manner,
using the default value if the the conversion fails.
| |||||||||||
Gets a Integer from a Map in a null-safe manner.
| |||||||||||
Looks up the given key in the given map, converting the result into
an integer, using the default value if the the conversion fails.
| |||||||||||
Looks up the given key in the given map, converting the result into
a long, using the default value if the the conversion fails.
| |||||||||||
Gets a Long from a Map in a null-safe manner.
| |||||||||||
Gets a long from a Map in a null-safe manner.
| |||||||||||
Gets a long from a Map in a null-safe manner,
using the default value if the the conversion fails.
| |||||||||||
Looks up the given key in the given map, converting the result into
a map, using the default value if the the conversion fails.
| |||||||||||
Gets a Map from a Map in a null-safe manner.
| |||||||||||
Looks up the given key in the given map, converting the result into
a number, using the default value if the the conversion fails.
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Gets a Number from a Map in a null-safe manner.
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Gets from a Map in a null-safe manner.
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Looks up the given key in the given map, converting null into the
given default value.
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Gets a Short from a Map in a null-safe manner.
| |||||||||||
Looks up the given key in the given map, converting the result into
a short, using the default value if the the conversion fails.
| |||||||||||
Gets a short from a Map in a null-safe manner,
using the default value if the the conversion fails.
| |||||||||||
Gets a short from a Map in a null-safe manner.
| |||||||||||
Looks up the given key in the given map, converting the result into
a string, using the default value if the the conversion fails.
| |||||||||||
Gets a String from a Map in a null-safe manner.
| |||||||||||
Inverts the supplied map returning a new HashMap such that the keys of
the input are swapped with the values.
| |||||||||||
Null-safe check if the specified map is empty.
| |||||||||||
Null-safe check if the specified map is not empty.
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Returns a "lazy" map whose values will be created on demand.
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Returns a "lazy" map whose values will be created on demand.
| |||||||||||
Returns a "lazy" sorted map whose values will be created on demand.
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Returns a "lazy" sorted map whose values will be created on demand.
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Creates a mult-value map backed by the given map which returns
collections of type ArrayList.
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Creates a multi-value map backed by the given map which returns
collections of the specified type.
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Creates a multi-value map backed by the given map which returns
collections created by the specified collection factory.
| |||||||||||
Returns a map that maintains the order of keys that are added
backed by the given map.
| |||||||||||
Returns a predicated (validating) map backed by the given map.
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Returns a predicated (validating) sorted map backed by the given map.
| |||||||||||
Puts all the keys and values from the specified array into the map.
| |||||||||||
Protects against adding null values to a map.
| |||||||||||
Returns a synchronized map backed by the given map.
| |||||||||||
Returns a synchronized sorted map backed by the given sorted map.
| |||||||||||
Creates a new HashMap using data copied from a ResourceBundle.
| |||||||||||
Gets a new Properties object initialised with the values from a Map.
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Returns a transformed map backed by the given map.
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Returns a transformed sorted map backed by the given map.
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Returns a typed map backed by the given map.
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Returns a typed sorted map backed by the given map.
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Returns an unmodifiable map backed by the given map.
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Returns an unmodifiable sorted map backed by the given sorted map.
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Prints the given map with nice line breaks.
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Protected Methods | |||||||||||
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Logs the given exception to
System.out . |
[Expand]
Inherited Methods | |||||||||||
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From class
java.lang.Object
|
An empty unmodifiable sorted map. This is not provided in the JDK.
MapUtils
should not normally be instantiated.
Prints the given map with nice line breaks.
This method prints a nicely formatted String describing the Map. Each map entry will be printed with key, value and value classname. When the value is a Map, recursive behaviour occurs.
This method is NOT thread-safe in any special way. You must manually synchronize on either this class or the stream as required.
out | the stream to print to, must not be null |
---|---|
label | The label to be used, may be null .
If null , the label is not output.
It typically represents the name of the property in a bean or similar. |
map | The map to print, may be null .
If null , the text 'null' is output. |
NullPointerException | if the stream is null
|
---|
Returns a fixed-sized map backed by the given map.
Elements may not be added or removed from the returned map, but
existing elements can be changed (for instance, via the
put(Object, Object)
method).
map | the map whose size to fix, must not be null |
---|
IllegalArgumentException | if the Map is null |
---|
Returns a fixed-sized sorted map backed by the given sorted map.
Elements may not be added or removed from the returned map, but
existing elements can be changed (for instance, via the
put(Object, Object)
method).
map | the map whose size to fix, must not be null |
---|
IllegalArgumentException | if the SortedMap is null |
---|
Looks up the given key in the given map, converting the result into a boolean, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a Boolean from a Map in a null-safe manner.
If the value is a Boolean
it is returned directly.
If the value is a String
and it equals 'true' ignoring case
then true
is returned, otherwise false
.
If the value is a Number
an integer zero value returns
false
and non-zero returns true
.
Otherwise, null
is returned.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Gets a boolean from a Map in a null-safe manner, using the default value if the the conversion fails.
If the value is a Boolean
its value is returned.
If the value is a String
and it equals 'true' ignoring case
then true
is returned, otherwise false
.
If the value is a Number
an integer zero value returns
false
and non-zero returns true
.
Otherwise, defaultValue
is returned.
map | the map to use |
---|---|
key | the key to look up |
defaultValue | return if the value is null or if the conversion fails |
defaultValue
if null map input
Gets a boolean from a Map in a null-safe manner.
If the value is a Boolean
its value is returned.
If the value is a String
and it equals 'true' ignoring case
then true
is returned, otherwise false
.
If the value is a Number
an integer zero value returns
false
and non-zero returns true
.
Otherwise, false
is returned.
map | the map to use |
---|---|
key | the key to look up |
false
if null map input
Gets a Byte from a Map in a null-safe manner.
The Byte is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Looks up the given key in the given map, converting the result into a byte, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a byte from a Map in a null-safe manner.
The byte is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
0
if null map input
Gets a byte from a Map in a null-safe manner, using the default value if the the conversion fails.
The byte is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
defaultValue | return if the value is null or if the conversion fails |
defaultValue
if null map input
Gets a Double from a Map in a null-safe manner.
The Double is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Looks up the given key in the given map, converting the result into a double, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a double from a Map in a null-safe manner.
The double is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
0.0
if null map input
Gets a double from a Map in a null-safe manner, using the default value if the the conversion fails.
The double is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
defaultValue | return if the value is null or if the conversion fails |
defaultValue
if null map input
Gets a Float from a Map in a null-safe manner.
The Float is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Looks up the given key in the given map, converting the result into a float, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a float from a Map in a null-safe manner, using the default value if the the conversion fails.
The float is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
defaultValue | return if the value is null or if the conversion fails |
defaultValue
if null map input
Gets a float from a Map in a null-safe manner.
The float is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
0.0F
if null map input
Gets an int from a Map in a null-safe manner.
The int is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
0
if null map input
Gets an int from a Map in a null-safe manner, using the default value if the the conversion fails.
The int is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
defaultValue | return if the value is null or if the conversion fails |
defaultValue
if null map input
Gets a Integer from a Map in a null-safe manner.
The Integer is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Looks up the given key in the given map, converting the result into an integer, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Looks up the given key in the given map, converting the result into a long, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a Long from a Map in a null-safe manner.
The Long is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Gets a long from a Map in a null-safe manner.
The long is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
0L
if null map input
Gets a long from a Map in a null-safe manner, using the default value if the the conversion fails.
The long is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
defaultValue | return if the value is null or if the conversion fails |
defaultValue
if null map input
Looks up the given key in the given map, converting the result into a map, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a Map from a Map in a null-safe manner.
If the value returned from the specified map is not a Map then
null
is returned.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Looks up the given key in the given map, converting the result into a number, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a Number from a Map in a null-safe manner.
If the value is a Number
it is returned directly.
If the value is a String
it is converted using
parse(String)
on the system default formatter
returning null
if the conversion fails.
Otherwise, null
is returned.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Gets from a Map in a null-safe manner.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Looks up the given key in the given map, converting null into the given default value.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null |
Gets a Short from a Map in a null-safe manner.
The Short is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Looks up the given key in the given map, converting the result into a short, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a short from a Map in a null-safe manner, using the default value if the the conversion fails.
The short is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
defaultValue | return if the value is null or if the conversion fails |
defaultValue
if null map input
Gets a short from a Map in a null-safe manner.
The short is obtained from the results of getNumber(Map, Object)
.
map | the map to use |
---|---|
key | the key to look up |
0
if null map input
Looks up the given key in the given map, converting the result into a string, using the default value if the the conversion fails.
map | the map whose value to look up |
---|---|
key | the key of the value to look up in that map |
defaultValue | what to return if the value is null or if the conversion fails |
Gets a String from a Map in a null-safe manner.
The String is obtained via toString
.
map | the map to use |
---|---|
key | the key to look up |
null
if null map input
Inverts the supplied map returning a new HashMap such that the keys of the input are swapped with the values.
This operation assumes that the inverse mapping is well defined. If the input map had multiple entries with the same value mapped to different keys, the returned map will map one of those keys to the value, but the exact key which will be mapped is undefined.
map | the map to invert, may not be null |
---|
NullPointerException | if the map is null |
---|
Null-safe check if the specified map is empty.
Null returns true.
map | the map to check, may be null |
---|
Null-safe check if the specified map is not empty.
Null returns false.
map | the map to check, may be null |
---|
Returns a "lazy" map whose values will be created on demand.
When the key passed to the returned map's get(Object)
method is not present in the map, then the factory will be used
to create a new object and that object will become the value
associated with that key.
For instance:
Factory factory = new Factory() { public Object create() { return new Date(); } } Map lazyMap = MapUtils.lazyMap(new HashMap(), factory); Object obj = lazyMap.get("test");After the above code is executed,
obj
will contain
a new Date
instance. Furthermore, that Date
instance is the value for the "test"
key in the map.map | the map to make lazy, must not be null |
---|---|
factory | the factory for creating new objects, must not be null |
IllegalArgumentException | if the Map or Factory is null |
---|
Returns a "lazy" map whose values will be created on demand.
When the key passed to the returned map's get(Object)
method is not present in the map, then the factory will be used
to create a new object and that object will become the value
associated with that key. The factory is a Transformer
that will be passed the key which it must transform into the value.
For instance:
Transformer factory = new Transformer() { public Object transform(Object mapKey) { return new File(mapKey); } } Map lazyMap = MapUtils.lazyMap(new HashMap(), factory); Object obj = lazyMap.get("C:/dev");After the above code is executed,
obj
will contain
a new File
instance for the C drive dev directory.
Furthermore, that File
instance is the value for the
"C:/dev"
key in the map.
If a lazy map is wrapped by a synchronized map, the result is a simple synchronized cache. When an object is not is the cache, the cache itself calls back to the factory Transformer to populate itself, all within the same synchronized block.
map | the map to make lazy, must not be null |
---|---|
transformerFactory | the factory for creating new objects, must not be null |
IllegalArgumentException | if the Map or Transformer is null |
---|
Returns a "lazy" sorted map whose values will be created on demand.
When the key passed to the returned map's get(Object)
method is not present in the map, then the factory will be used
to create a new object and that object will become the value
associated with that key.
For instance:
Factory factory = new Factory() { public Object create() { return new Date(); } } SortedMap lazy = MapUtils.lazySortedMap(new TreeMap(), factory); Object obj = lazy.get("test");After the above code is executed,
obj
will contain
a new Date
instance. Furthermore, that Date
instance is the value for the "test"
key.map | the map to make lazy, must not be null |
---|---|
factory | the factory for creating new objects, must not be null |
IllegalArgumentException | if the SortedMap or Factory is null |
---|
Returns a "lazy" sorted map whose values will be created on demand.
When the key passed to the returned map's get(Object)
method is not present in the map, then the factory will be used
to create a new object and that object will become the value
associated with that key. The factory is a Transformer
that will be passed the key which it must transform into the value.
For instance:
Transformer factory = new Transformer() { public Object transform(Object mapKey) { return new File(mapKey); } } SortedMap lazy = MapUtils.lazySortedMap(new TreeMap(), factory); Object obj = lazy.get("C:/dev");After the above code is executed,
obj
will contain
a new File
instance for the C drive dev directory.
Furthermore, that File
instance is the value for the
"C:/dev"
key in the map.
If a lazy map is wrapped by a synchronized map, the result is a simple synchronized cache. When an object is not is the cache, the cache itself calls back to the factory Transformer to populate itself, all within the same synchronized block.
map | the map to make lazy, must not be null |
---|---|
transformerFactory | the factory for creating new objects, must not be null |
IllegalArgumentException | if the Map or Transformer is null |
---|
Creates a mult-value map backed by the given map which returns collections of type ArrayList.
map | the map to decorate |
---|
Creates a multi-value map backed by the given map which returns collections of the specified type.
map | the map to decorate |
---|---|
collectionClass | the type of collections to return from the map (must contain public no-arg constructor and extend Collection). |
Creates a multi-value map backed by the given map which returns collections created by the specified collection factory.
map | the map to decorate |
---|---|
collectionFactory | a factor which creates collection objects |
Returns a map that maintains the order of keys that are added backed by the given map.
If a key is added twice, the order is determined by the first add. The order is observed through the keySet, values and entrySet.
map | the map to order, must not be null |
---|
IllegalArgumentException | if the Map is null |
---|
Returns a predicated (validating) map backed by the given map.
Only objects that pass the tests in the given predicates can be added to the map. Trying to add an invalid object results in an IllegalArgumentException. Keys must pass the key predicate, values must pass the value predicate. It is important not to use the original map after invoking this method, as it is a backdoor for adding invalid objects.
map | the map to predicate, must not be null |
---|---|
keyPred | the predicate for keys, null means no check |
valuePred | the predicate for values, null means no check |
IllegalArgumentException | if the Map is null |
---|
Returns a predicated (validating) sorted map backed by the given map.
Only objects that pass the tests in the given predicates can be added to the map. Trying to add an invalid object results in an IllegalArgumentException. Keys must pass the key predicate, values must pass the value predicate. It is important not to use the original map after invoking this method, as it is a backdoor for adding invalid objects.
map | the map to predicate, must not be null |
---|---|
keyPred | the predicate for keys, null means no check |
valuePred | the predicate for values, null means no check |
IllegalArgumentException | if the SortedMap is null |
---|
Puts all the keys and values from the specified array into the map.
This method is an alternative to the putAll(java.util.Map)
method and constructors. It allows you to build a map from an object array
of various possible styles.
If the first entry in the object array implements java.util.Map.Entry
or KeyValue
then the key and value are added from that object.
If the first entry in the object array is an object array itself, then
it is assumed that index 0 in the sub-array is the key and index 1 is the value.
Otherwise, the array is treated as keys and values in alternate indices.
For example, to create a color map:
Map colorMap = MapUtils.putAll(new HashMap(), new String[][] { {"RED", "#FF0000"}, {"GREEN", "#00FF00"}, {"BLUE", "#0000FF"} });or:
Map colorMap = MapUtils.putAll(new HashMap(), new String[] { "RED", "#FF0000", "GREEN", "#00FF00", "BLUE", "#0000FF" });or:
Map colorMap = MapUtils.putAll(new HashMap(), new Map.Entry[] { new DefaultMapEntry("RED", "#FF0000"), new DefaultMapEntry("GREEN", "#00FF00"), new DefaultMapEntry("BLUE", "#0000FF") });
map | the map to populate, must not be null |
---|---|
array | an array to populate from, null ignored |
NullPointerException | if map is null |
---|---|
IllegalArgumentException | if sub-array or entry matching used and an entry is invalid |
ClassCastException | if the array contents is mixed |
Protects against adding null values to a map.
This method checks the value being added to the map, and if it is null it is replaced by an empty string.
This could be useful if the map does not accept null values, or for receiving data from a source that may provide null or empty string which should be held in the same way in the map.
Keys are not validated.
map | the map to add to, may not be null |
---|---|
key | the key |
value | the value, null converted to "" |
NullPointerException | if the map is null |
---|
Returns a synchronized map backed by the given map.
You must manually synchronize on the returned buffer's iterator to avoid non-deterministic behavior:
Map m = MapUtils.synchronizedMap(myMap); Set s = m.keySet(); // outside synchronized block synchronized (m) { // synchronized on MAP! Iterator i = s.iterator(); while (i.hasNext()) { process (i.next()); } }This method uses the implementation in java.util.Collections Collections.
map | the map to synchronize, must not be null |
---|
IllegalArgumentException | if the map is null |
---|
Returns a synchronized sorted map backed by the given sorted map.
You must manually synchronize on the returned buffer's iterator to avoid non-deterministic behavior:
Map m = MapUtils.synchronizedSortedMap(myMap); Set s = m.keySet(); // outside synchronized block synchronized (m) { // synchronized on MAP! Iterator i = s.iterator(); while (i.hasNext()) { process (i.next()); } }This method uses the implementation in java.util.Collections Collections.
map | the map to synchronize, must not be null |
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IllegalArgumentException | if the map is null |
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Creates a new HashMap using data copied from a ResourceBundle.
resourceBundle | the resource bundle to convert, may not be null |
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NullPointerException | if the bundle is null |
---|
Gets a new Properties object initialised with the values from a Map. A null input will return an empty properties object.
map | the map to convert to a Properties object, may not be null |
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Returns a transformed map backed by the given map.
This method returns a new map (decorating the specified map) that
will transform any new entries added to it.
Existing entries in the specified map will not be transformed.
If you want that behaviour, see decorateTransform(Map, Transformer, Transformer)
.
Each object is passed through the transformers as it is added to the Map. It is important not to use the original map after invoking this method, as it is a backdoor for adding untransformed objects.
If there are any elements already in the map being decorated, they are NOT transformed.
map | the map to transform, must not be null, typically empty |
---|---|
keyTransformer | the transformer for the map keys, null means no transformation |
valueTransformer | the transformer for the map values, null means no transformation |
IllegalArgumentException | if the Map is null |
---|
Returns a transformed sorted map backed by the given map.
This method returns a new sorted map (decorating the specified map) that
will transform any new entries added to it.
Existing entries in the specified map will not be transformed.
If you want that behaviour, see decorateTransform(Map, Transformer, Transformer)
.
Each object is passed through the transformers as it is added to the Map. It is important not to use the original map after invoking this method, as it is a backdoor for adding untransformed objects.
If there are any elements already in the map being decorated, they are NOT transformed.
map | the map to transform, must not be null, typically empty |
---|---|
keyTransformer | the transformer for the map keys, null means no transformation |
valueTransformer | the transformer for the map values, null means no transformation |
IllegalArgumentException | if the SortedMap is null |
---|
Returns a typed map backed by the given map.
Only keys and values of the specified types can be added to the map.
map | the map to limit to a specific type, must not be null |
---|---|
keyType | the type of keys which may be added to the map, must not be null |
valueType | the type of values which may be added to the map, must not be null |
IllegalArgumentException | if the Map or Class is null |
---|
Returns a typed sorted map backed by the given map.
Only keys and values of the specified types can be added to the map.
map | the map to limit to a specific type, must not be null |
---|---|
keyType | the type of keys which may be added to the map, must not be null |
valueType | the type of values which may be added to the map, must not be null |
Returns an unmodifiable map backed by the given map.
This method uses the implementation in the decorators subpackage.
map | the map to make unmodifiable, must not be null |
---|
IllegalArgumentException | if the map is null |
---|
Returns an unmodifiable sorted map backed by the given sorted map.
This method uses the implementation in the decorators subpackage.
map | the sorted map to make unmodifiable, must not be null |
---|
IllegalArgumentException | if the map is null |
---|
Prints the given map with nice line breaks.
This method prints a nicely formatted String describing the Map. Each map entry will be printed with key and value. When the value is a Map, recursive behaviour occurs.
This method is NOT thread-safe in any special way. You must manually synchronize on either this class or the stream as required.
out | the stream to print to, must not be null |
---|---|
label | The label to be used, may be null .
If null , the label is not output.
It typically represents the name of the property in a bean or similar. |
map | The map to print, may be null .
If null , the text 'null' is output. |
NullPointerException | if the stream is null
|
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Logs the given exception to System.out
.
This method exists as Jakarta Collections does not depend on logging.
ex | the exception to log |
---|