brooklyn.util.internal
[Groovy] Class LanguageUtils

java.lang.Object
  brooklyn.util.internal.LanguageUtils

@Deprecated
@Beta
class LanguageUtils

Useful Groovy utility methods.

deprecated:

since 0.5; requires thorough review for what will be kept. e.g. consider instead using guava's com.google.common.collect.Multimap instead of addToMapOfSets etc

DEFAULT_FIELD_GETTER

public static final groovy.lang.Closure DEFAULT_FIELD_GETTER

Default field getter. Delegates to object[field] (which will invoke a getter if one exists, in groovy), unless field starts with {

literal:

@} in which case it looks up the actual java field (bypassing getter).

Can be extended as needed when passed to equals(Object, Object, Class, String[])

NO_SUCH_FIELD

public static final java.lang.Object NO_SUCH_FIELD

return value used to indicate that there is no such field

addToMapOfLists

@Deprecated
static java.util.List addToMapOfLists(java.util.Map map, java.lang.Object key, java.lang.Object valueInCollection)

as addToMapOfSets(Map, Object, Object) but for java.util.ArrayList

deprecated:

since 0.5; use ArrayListMultimap, and Multimaps#synchronizedListMultimap(com.google.common.collect.ListMultimap)

addToMapOfSets

@Deprecated
static java.util.Set addToMapOfSets(java.util.Map map, java.lang.Object key, java.lang.Object valueInCollection)

Adds the given value to a collection in the map under the key. A collection (as java.util.LinkedHashMap) will be created if necessary, synchronized on map for map access/change and set for addition there

deprecated:

since 0.5; use HashMultimap, and Multimaps#synchronizedSetMultimap(com.google.common.collect.SetMultimap)

Returns:

the updated set (instance, not copy)

deserialize

static java.lang.Object deserialize(byte[] bytes, java.lang.ClassLoader classLoader)

equals

static boolean equals(java.lang.Object o1, java.lang.Object o2, java.lang.Class optionalCommonSuperClass = null, groovy.lang.Closure optionalGetter = null, java.lang.Iterable fieldNames)

Checks equality of o1 and o2 with respect to the named fields, optionally enforcing a common superclass and using a custom field-getter. Other types can be supplied if they are supported by object[field] (what the DEFAULT_FIELD_GETTER does) or if the {

literal:

optionalGetter} handles it. Note that object[field] causes invocation of object.getAt(field) (which can be provided on the object for non-strings - this is preferred to an optionalGetter, generally) looking for object.getXxx(), where field is a string {@literal xxx}, then object.xxx.

One exception is that field names which start with {@literal

@} get the field directly according to DEFAULT_FIELD_GETTER, but use with care on private fields, as they must be on the object and not a superclass, and with groovy properties (formerly known as package-private, i.e. with no access modifiers) because they become private fields.

For example

 public class Foo {
   Object bar;
   public boolean equals(Object other) { LangaugeUtils.equals(this, other, Foo.class, ["bar"]); }
   public int hashCode() { LangaugeUtils.hashCode(this, ["bar"]); }
 }
 

Parameters:

o1 - one object to compare

o2 - other object to compare

optionalCommonSuperClass - if supplied, returns false unless both objects are instances of the given type; (if not supplied it effectively does duck typing, returning false if any field is not present)

optionalGetter - if supplied, a closure which takes (object, field) and returns the value of field on object; should return static NO_SUCH_FIELD if none found; recommended to delegate to DEFAULT_FIELD_GETTER at least for strings (or for anything)

fields - typically a list of strings being names of fields on the class to compare

Returns:

true if the two objects are equal in all indicated fields, and conform to the optionalCommonSuperClass if supplied

equals

static boolean equals(java.lang.Object o1, java.lang.Object o2, java.lang.Class optionalCommonSuperClass = null, groovy.lang.Closure optionalGetter = null, java.lang.Object[] fieldNames)

forBoth

static java.util.Collection forBoth(java.util.Collection l1, java.util.Collection l2, groovy.lang.Closure code)

Iterates through two collections simultaneously, passing both args to code.

 a = ['a','b']; b=[1,2];
 assert ['a1','b2'] == forboth(a,b) { x,y -> x+y }
 

forBoth

static java.util.Collection forBoth(java.lang.Object[] l1, java.lang.Object[] l2, groovy.lang.Closure code)

forBothWithIndex

static java.util.Collection forBothWithIndex(java.util.Collection l1, java.util.Collection l2, groovy.lang.Closure code)

forBothWithIndex

static java.util.Collection forBothWithIndex(java.lang.Object[] l1, java.lang.Object[] l2, groovy.lang.Closure code)

getOptionalField

static java.lang.Object getOptionalField(java.lang.String name, java.util.Map m, java.lang.Object defaultValue = null)

getPropertySafe

static java.lang.Object getPropertySafe(java.lang.Object target, java.lang.String name, java.lang.Object defaultValue = null)

getRequiredField

static java.lang.Object getRequiredField(java.lang.String name, java.util.Map m)

hashCode

static int hashCode(java.lang.Object o, groovy.lang.Closure optionalGetter = null, java.util.Collection fieldNames)

Generates a hashcode for an object. Similar to com.google.common.base.Objects#hashCode() but taking field names and an optional getter, with the same rich groovy semantics as described in equals(Object, Object, Class).

hashCode

static int hashCode(java.lang.Object o, groovy.lang.Closure optionalGetter = null, java.lang.Object[] fieldNames)

newUid

@Deprecated
static java.lang.String newUid()

deprecated:

use Identifiers.makeRandomId(8)

removeFromMapOfCollections

@Deprecated
static boolean removeFromMapOfCollections(java.util.Map map, java.lang.Object key, java.lang.Object valueInCollection)

Removes the given value from a collection in the map under the key.

deprecated:

since 0.5; use ArrayListMultimap or HashMultimap, and Multimaps#synchronizedListMultimap(com.google.common.collect.ListMultimap) etc

Returns:

the updated set (instance, not copy)

serialize

static byte[] serialize(java.lang.Object orig)

setFieldsFromMap

static java.util.Map setFieldsFromMap(java.lang.Object target, java.util.Map fieldValues)

toString

static java.lang.String toString(java.lang.Object o, groovy.lang.Closure optionalGetter = null, java.util.Collection fieldNames)

Default String representation is simplified name of class, together with selected fields.

visitFields

static void visitFields(java.lang.Object o, LanguageUtils.FieldVisitor fv, java.util.Collection objectsToSkip = ([] as Set)

Visits all fields of a given object, recursively. For collections, arrays, and maps it visits the items within, passing null for keys where it isn't a map.

Brooklyn Multi-Cloud Application Management Platform
brooklyncentral.github.com. Apache License. © 2012.