JavaConverters (original) (raw)
scala.collection.JavaConverters
A variety of decorators that enable converting between Scala and Java collections using extension methods, asScala and asJava.
The extension methods return adapters for the corresponding API.
The following conversions are supported via asScala and asJava:
scala.collection.Iterable <=> java.lang.Iterable
scala.collection.Iterator <=> java.util.Iterator
scala.collection.mutable.Buffer <=> java.util.List
scala.collection.mutable.Set <=> java.util.Set
scala.collection.mutable.Map <=> java.util.Map
scala.collection.concurrent.Map <=> java.util.concurrent.ConcurrentMap
The following conversions are supported via asScala and through specially-named extension methods to convert to Java collections, as shown:
scala.collection.Iterable <=> java.util.Collection (via asJavaCollection)
scala.collection.Iterator <=> java.util.Enumeration (via asJavaEnumeration)
scala.collection.mutable.Map <=> java.util.Dictionary (via asJavaDictionary)
In addition, the following one-way conversions are provided via asJava:
scala.collection.Seq => java.util.List
scala.collection.mutable.Seq => java.util.List
scala.collection.Set => java.util.Set
scala.collection.Map => java.util.Map
The following one way conversion is provided via asScala:
java.util.Properties => scala.collection.mutable.Map
In all cases, converting from a source type to a target type and back again will return the original source object. For example:
import scala.collection.JavaConverters._
val source = new scala.collection.mutable.ListBuffer[Int]
val target: java.util.List[Int] = source.asJava
val other: scala.collection.mutable.Buffer[Int] = target.asScala
assert(source eq other)
Alternatively, the conversion methods have descriptive names and can be invoked explicitly.
scala> val vs = java.util.Arrays.asList("hi", "bye")
vs: java.util.List[String] = [hi, bye]
scala> val ss = asScalaIterator(vs.iterator)
ss: Iterator[String] = <iterator>
scala> .toList
res0: List[String] = List(hi, bye)
scala> val ss = asScalaBuffer(vs)
ss: scala.collection.mutable.Buffer[String] = Buffer(hi, bye)
Attributes
Deprecated
[Since version 2.13.0] Use `scala.jdk.CollectionConverters` instead
Source
Graph
Supertypes
Self type
Members list
Generic class containing the asJava converter method
Generic class containing the asJava converter method
Attributes
Source
Supertypes
Generic class containing the asJavaCollection converter method
Generic class containing the asJavaCollection converter method
Attributes
Source
Supertypes
Generic class containing the asJavaDictionary converter method
Generic class containing the asJavaDictionary converter method
Attributes
Source
Supertypes
Generic class containing the asJavaEnumeration converter method
Generic class containing the asJavaEnumeration converter method
Attributes
Source
Supertypes
Generic class containing the asScala converter method
Generic class containing the asScala converter method
Attributes
Source
Supertypes
Converts a Scala mutable concurrent.Map to a Java ConcurrentMap.
Converts a Scala mutable concurrent.Map to a Java ConcurrentMap.
The returned Java ConcurrentMap is backed by the provided Scala concurrent.Map and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala concurrent.Map was previously obtained from an implicit or explicit call of asScala then the original Java ConcurrentMap will be returned.
Value parameters
m
The Scala concurrent.Map to be converted.
Attributes
Returns
A Java ConcurrentMap view of the argument.
Inherited from:
Source
Converts a Scala Map to a Java Map.
Converts a Scala Map to a Java Map.
The returned Java Map is backed by the provided Scala Map and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Map was previously obtained from an implicit or explicit call of asScala then the original Java Map will be returned.
Value parameters
m
The Scala Map to be converted.
Attributes
Returns
A Java Map view of the argument.
Inherited from:
Source
Converts a Scala mutable Map to a Java Map.
Converts a Scala mutable Map to a Java Map.
The returned Java Map is backed by the provided Scala Map and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Map was previously obtained from an implicit or explicit call of asScala then the original Java Map will be returned.
Value parameters
m
The Scala mutable Map to be converted.
Attributes
Returns
A Java Map view of the argument.
Inherited from:
Source
Converts a Scala Set to a Java Set.
Converts a Scala Set to a Java Set.
The returned Java Set is backed by the provided Scala Set and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Set was previously obtained from an implicit or explicit call of asScala then the original Java Set will be returned.
Value parameters
s
The Scala Set to be converted.
Attributes
Returns
A Java Set view of the argument.
Inherited from:
Source
Converts a Scala mutable Set to a Java Set.
Converts a Scala mutable Set to a Java Set.
The returned Java Set is backed by the provided Scala Set and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Set was previously obtained from an implicit or explicit call of asScala then the original Java Set will be returned.
Value parameters
s
The Scala mutable Set to be converted.
Attributes
Returns
A Java Set view of the argument.
Inherited from:
Source
Converts a Scala Seq to a Java List.
Converts a Scala Seq to a Java List.
The returned Java List is backed by the provided Scala Seq and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Seq was previously obtained from an implicit or explicit call of asScala then the original Java List will be returned.
Value parameters
s
The Scala Seq to be converted.
Attributes
Returns
A Java List view of the argument.
Inherited from:
Source
Converts a Scala mutable Seq to a Java List.
Converts a Scala mutable Seq to a Java List.
The returned Java List is backed by the provided Scala Seq and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Seq was previously obtained from an implicit or explicit call of asScala then the original Java List will be returned.
Value parameters
s
The Scala Seq to be converted.
Attributes
Returns
A Java List view of the argument.
Inherited from:
Source
Converts a Scala mutable Buffer to a Java List.
Converts a Scala mutable Buffer to a Java List.
The returned Java List is backed by the provided Scala Buffer and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Buffer was previously obtained from an implicit or explicit call of asScala then the original Java List will be returned.
Value parameters
b
The Scala Buffer to be converted.
Attributes
Returns
A Java List view of the argument.
Inherited from:
Source
Converts a Scala Iterable to a Java Iterable.
Converts a Scala Iterable to a Java Iterable.
The returned Java Iterable is backed by the provided Scala Iterable and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Iterable was previously obtained from an implicit or explicit call of asScala then the original Java Iterable will be returned.
Value parameters
i
The Scala Iterable to be converted.
Attributes
Returns
A Java Iterable view of the argument.
Inherited from:
Source
Converts a Scala Iterator to a Java Iterator.
Converts a Scala Iterator to a Java Iterator.
The returned Java Iterator is backed by the provided Scala Iterator and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Iterator was previously obtained from an implicit or explicit call of asScala then the original Java Iterator will be returned.
Value parameters
i
The Scala Iterator to be converted.
Attributes
Returns
A Java Iterator view of the argument.
Inherited from:
Source
Converts a Scala Iterable to an immutable Java Collection.
Converts a Scala Iterable to an immutable Java Collection.
If the Scala Iterable was previously obtained from an implicit or explicit call of asScala then the original Java Collection will be returned.
Value parameters
i
The Scala Iterable to be converted.
Attributes
Returns
A Java Collection view of the argument.
Inherited from:
Source
Converts a Scala mutable Map to a Java Dictionary.
Converts a Scala mutable Map to a Java Dictionary.
The returned Java Dictionary is backed by the provided Scala Dictionary and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Map was previously obtained from an implicit or explicit call of asScala then the original Java Dictionary will be returned.
Value parameters
m
The Scala Map to be converted.
Attributes
Returns
A Java Dictionary view of the argument.
Inherited from:
Source
Converts a Scala Iterator to a Java Enumeration.
Converts a Scala Iterator to a Java Enumeration.
The returned Java Enumeration is backed by the provided Scala Iterator and any side-effects of using it via the Java interface will be visible via the Scala interface and vice versa.
If the Scala Iterator was previously obtained from an implicit or explicit call of asScala then the original Java Enumeration will be returned.
Value parameters
i
The Scala Iterator to be converted.
Attributes
Returns
A Java Enumeration view of the argument.
Inherited from:
Source
Converts a Java Properties to a Scala mutable Map[String, String].
Converts a Java Properties to a Scala mutable Map[String, String].
The returned Scala Map[String, String] is backed by the provided Java Properties and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
Value parameters
p
The Java Properties to be converted.
Attributes
Returns
A Scala mutable Map[String, String] view of the argument.
Inherited from:
Source
Converts a Java Dictionary to a Scala mutable Map.
Converts a Java Dictionary to a Scala mutable Map.
The returned Scala Map is backed by the provided Java Dictionary and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
If the Java Dictionary was previously obtained from an implicit or explicit call of asJavaDictionary then the original Scala Map will be returned.
Value parameters
d
The Java Dictionary to be converted.
Attributes
Returns
A Scala mutable Map view of the argument.
Inherited from:
Source
Converts a Java ConcurrentMap to a Scala mutable ConcurrentMap.
Converts a Java ConcurrentMap to a Scala mutable ConcurrentMap.
The returned Scala ConcurrentMap is backed by the provided Java ConcurrentMap and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
If the Java ConcurrentMap was previously obtained from an implicit or explicit call of asJava then the original Scala ConcurrentMap will be returned.
Value parameters
m
The Java ConcurrentMap to be converted.
Attributes
Returns
A Scala mutable ConcurrentMap view of the argument.
Inherited from:
Source
Converts a Java Map to a Scala mutable Map.
Converts a Java Map to a Scala mutable Map.
The returned Scala Map is backed by the provided Java Map and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
If the Java Map was previously obtained from an implicit or explicit call of asJava then the original Scala Map will be returned.
If the wrapped map is synchronized (e.g. from java.util.Collections.synchronizedMap), it is your responsibility to wrap all non-atomic operations with underlying.synchronized. This includes get, as java.util.Map's API does not allow for an atomic get when null values may be present.
Value parameters
m
The Java Map to be converted.
Attributes
Returns
A Scala mutable Map view of the argument.
Inherited from:
Source
Converts a Java Set to a Scala mutable Set.
Converts a Java Set to a Scala mutable Set.
The returned Scala Set is backed by the provided Java Set and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
If the Java Set was previously obtained from an implicit or explicit call of asJava then the original Scala Set will be returned.
Value parameters
s
The Java Set to be converted.
Attributes
Returns
A Scala mutable Set view of the argument.
Inherited from:
Source
Converts a Java List to a Scala mutable Buffer.
Converts a Java List to a Scala mutable Buffer.
The returned Scala Buffer is backed by the provided Java List and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
If the Java List was previously obtained from an implicit or explicit call of asJava then the original Scala Buffer will be returned.
Value parameters
l
The Java List to be converted.
Attributes
Returns
A Scala mutable Buffer view of the argument.
Inherited from:
Source
Converts a Java Collection to a Scala Iterable.
Converts a Java Collection to a Scala Iterable.
If the Java Collection was previously obtained from an implicit or explicit call of asJavaCollection then the original Scala Iterable will be returned.
Value parameters
c
The Java Collection to be converted.
Attributes
Returns
A Scala Iterable view of the argument.
Inherited from:
Source
Converts a Java Iterable to a Scala Iterable.
Converts a Java Iterable to a Scala Iterable.
The returned Scala Iterable is backed by the provided Java Iterable and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
If the Java Iterable was previously obtained from an implicit or explicit call of asJava then the original Scala Iterable will be returned.
Value parameters
i
The Java Iterable to be converted.
Attributes
Returns
A Scala Iterable view of the argument.
Inherited from:
Source
Converts a Java Enumeration to a Scala Iterator.
Converts a Java Enumeration to a Scala Iterator.
The returned Scala Iterator is backed by the provided Java Enumeration and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
If the Java Enumeration was previously obtained from an implicit or explicit call of asJavaEnumeration then the original Scala Iterator will be returned.
Value parameters
e
The Java Enumeration to be converted.
Attributes
Returns
A Scala Iterator view of the argument.
Inherited from:
Source
Converts a Java Iterator to a Scala Iterator.
Converts a Java Iterator to a Scala Iterator.
The returned Scala Iterator is backed by the provided Java Iterator and any side-effects of using it via the Scala interface will be visible via the Java interface and vice versa.
If the Java Iterator was previously obtained from an implicit or explicit call of asJava then the original Scala Iterator will be returned.
Value parameters
i
The Java Iterator to be converted.
Attributes
Returns
A Scala Iterator view of the argument.
Inherited from:
Source
Adds an asJavaCollection method that implicitly converts a Scala Iterable to an immutable Java Collection.
Adds an asJavaCollection method that implicitly converts a Scala Iterable to an immutable Java Collection.
Attributes
See also
Source
Adds an asJavaDictionary method that implicitly converts a Scala mutable Map to a Java Dictionary.
Adds an asJavaDictionary method that implicitly converts a Scala mutable Map to a Java Dictionary.
Attributes
See also
Source
Adds an asJavaEnumeration method that implicitly converts a Scala Iterator to a Java Enumeration.
Adds an asJavaEnumeration method that implicitly converts a Scala Iterator to a Java Enumeration.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala Iterable to a Java Iterable.
Adds an asJava method that implicitly converts a Scala Iterable to a Java Iterable.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala Iterator to a Java Iterator.
Adds an asJava method that implicitly converts a Scala Iterator to a Java Iterator.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java List to a Scala mutable Buffer.
Adds an asScala method that implicitly converts a Java List to a Scala mutable Buffer.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java Iterator to a Scala Iterator.
Adds an asScala method that implicitly converts a Java Iterator to a Scala Iterator.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java Set to a Scala mutable Set.
Adds an asScala method that implicitly converts a Java Set to a Scala mutable Set.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala mutable Buffer to a Java List.
Adds an asJava method that implicitly converts a Scala mutable Buffer to a Java List.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java Collection to an Scala Iterable.
Adds an asScala method that implicitly converts a Java Collection to an Scala Iterable.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java Dictionary to a Scala mutable Map.
Adds an asScala method that implicitly converts a Java Dictionary to a Scala mutable Map.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java Enumeration to a Scala Iterator.
Adds an asScala method that implicitly converts a Java Enumeration to a Scala Iterator.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java Iterable to a Scala Iterable.
Adds an asScala method that implicitly converts a Java Iterable to a Scala Iterable.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala mutable concurrent.Map to a Java ConcurrentMap.
Adds an asJava method that implicitly converts a Scala mutable concurrent.Map to a Java ConcurrentMap.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala Map to a Java Map.
Adds an asJava method that implicitly converts a Scala Map to a Java Map.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java ConcurrentMap to a Scala mutable concurrent.Map.
Adds an asScala method that implicitly converts a Java ConcurrentMap to a Scala mutable concurrent.Map.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java Map to a Scala mutable Map.
Adds an asScala method that implicitly converts a Java Map to a Scala mutable Map.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala mutable Map to a Java Map.
Adds an asJava method that implicitly converts a Scala mutable Map to a Java Map.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala mutable Seq to a Java List.
Adds an asJava method that implicitly converts a Scala mutable Seq to a Java List.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala mutable Set to a Java Set.
Adds an asJava method that implicitly converts a Scala mutable Set to a Java Set.
Attributes
See also
Source
Adds an asScala method that implicitly converts a Java Properties to a Scala mutable Map[String, String].
Adds an asScala method that implicitly converts a Java Properties to a Scala mutable Map[String, String].
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala Seq to a Java List.
Adds an asJava method that implicitly converts a Scala Seq to a Java List.
Attributes
See also
Source
Adds an asJava method that implicitly converts a Scala Set to a Java Set.
Adds an asJava method that implicitly converts a Scala Set to a Java Set.
Attributes
See also
Source
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