Package com.atlassian.jira.util.collect

Class MapBuilder<K,V>

java.lang.Object
com.atlassian.jira.util.collect.MapBuilder<K,V>
Type Parameters:
K - the key type
V - the value type
public class MapBuilder<K,V> extends Object
Utility for easily creating Maps of all standard types. If your map does not need to contain null as either a key or a value, then ImmutableMap.builder() should be preferred.

  • Field Details

    • map

      protected final Map<K,V> map

  • Constructor Details

    • MapBuilder

      protected MapBuilder()
      prefer newBuilder() for inferred generic arguments.

  • Method Details

    • emptyMap

      public static <K, V> Map<K,V> emptyMap()
      Static factory method for creating an empty map. This is exactly equivalent to Collections.emptyMap() and is provided only for completeness.
      Type Parameters:
      K - the key type
      V - the value type
      Returns:
      an empty immutable map

    • newBuilder

      public static <K, V> MapBuilder<K,V> newBuilder()
      Static factory method for creating a fresh MapBuilder.
      Type Parameters:
      K - the key type
      V - the value type
      Returns:
      a new empty MapBuilder

    • newBuilder

      public static <K, V> MapBuilder<K,V> newBuilder(K key, V value)
      Static factory method for creating a fresh MapBuilder and adding the given key/value pair.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key - the key
      value - the value
      Returns:
      a new MapBuilder

    • newBuilder

      public static <K, V> MapBuilder<K,V> newBuilder(K key1, V value1, K key2, V value2)
      Static factory method for creating a fresh MapBuilder and adding the given key/value pairs.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key1 - the key
      value1 - the value
      key2 - the key
      value2 - the value
      Returns:
      a new MapBuilder with the specified elements

    • newBuilder

      public static <K, V> MapBuilder<K,V> newBuilder(K key1, V value1, K key2, V value2, K key3, V value3)
      Static factory method for creating a fresh MapBuilder and adding the given key/value pairs.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key1 - the key
      value1 - the value
      key2 - the key
      value2 - the value
      key3 - the key
      value3 - the value
      Returns:
      a new MapBuilder with the specified elements

    • newBuilder

      public static <K, V> MapBuilder<K,V> newBuilder(K key1, V value1, K key2, V value2, K key3, V value3, K key4, V value4)
      Static factory method for creating a fresh MapBuilder and adding the given key/value pairs.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key1 - the key
      value1 - the value
      key2 - the key
      value2 - the value
      key3 - the key
      value3 - the value
      key4 - the key
      value4 - the value
      Returns:
      a new MapBuilder with the specified elements

    • newBuilder

      public static <K, V> MapBuilder<K,V> newBuilder(@Nullable Map<? extends K,? extends V> map)
      Static factory method for creating a fresh MapBuilder based on the contents of a source Map.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      map - the source map, may be null
      Returns:
      a new MapBuilder, populated with the values from map, if one is provided

    • singletonMap

      public static <K, V> Map<K,V> singletonMap(K key, V value)
      Static factory method for creating an immutable Map with a single entry. This is exactly equivalent to Collections.singletonMap(key, value) and is only provided for completeness.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key - the key
      value - the value
      Returns:
      a new empty MapBuilder

    • build

      public static <K, V> Map<K,V> build(K key, V value)
      Returns an immutable Map containing the given key-value pair. Prefer ImmutableMap.of(Object, Object) if neither key nor value will ever need to be null.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key - The Key
      value - The Value
      Returns:
      an immutable Map containing the given key-value pair.

    • build

      public static <K, V> Map<K,V> build(K key1, V value1, K key2, V value2)
      Returns an immutable Map containing the given key-value pairs. Prefer ImmutableMap.of(Object, Object, Object, Object) if none of the keys or values will ever need to be null.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key1 - The Key
      value1 - The Value
      key2 - The Key
      value2 - The Value
      Returns:
      an immutable Map containing the given key-value pair.

    • build

      public static <K, V> Map<K,V> build(K key1, @Nullable V value1, K key2, @Nullable V value2, K key3, @Nullable V value3)
      Returns an immutable Map containing the given key-value pairs. Prefer ImmutableMap.of(Object, Object, Object, Object, Object, Object) if none of the keys or values will ever need to be null.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key1 - The Key
      value1 - The Value
      key2 - The Key
      value2 - The Value
      key3 - The Key
      value3 - The Value
      Returns:
      an immutable Map containing the given key-value pair.

    • build

      public static <K, V> Map<K,V> build(K key1, V value1, K key2, V value2, K key3, V value3, K key4, V value4)
      Returns an immutable Map containing the given key-value pairs. Prefer ImmutableMap.of(Object, Object, Object, Object, Object, Object, Object, Object) if none of the keys or values will ever need to be null.
      Type Parameters:
      K - the key type
      V - the value type
      Parameters:
      key1 - The Key
      value1 - The Value
      key2 - The Key
      value2 - The Value
      key3 - The Key
      value3 - The Value
      key4 - The Key
      value4 - The Value
      Returns:
      an immutable Map containing the given key-value pair.

    • add

      public MapBuilder<K,V> add(@Nullable K key, @Nullable V value)
      Add a key/value. Allows nulls. Prefer ImmutableMap.builder() if that is not needed.
      Parameters:
      key - the key
      value - the value
      Returns:
      this

    • addIfValueNotNull

      public MapBuilder<K,V> addIfValueNotNull(K key, @Nullable V value)
      Add a key/value only if the value is not null. If the intent is to produce an immutable map that does not contain null values, then ImmutableMap should be preferred. This method should only be useful when intending to call toMutableMap().
      Parameters:
      key - the key
      value - the value
      Returns:
      this

    • addAll

      public MapBuilder<K,V> addAll(@Nullable Map<? extends K,? extends V> map)
      Add all the entries contained in the map. Accepts a null map and does nothing.
      Parameters:
      map - the map to add
      Returns:
      this

    • toMap

      public Map<K,V> toMap()
      Returns an immutable Map where the entries are in no defined order. The map may contain nulls. If this ability is not needed, then ImmutableMap is preferred.
      Returns:
      an immutable Map where the entries are in no defined order.

    • toHashMap

      public HashMap<K,V> toHashMap()
      Returns a mutable HashMap where the entries are in no defined order.
      Returns:
      a mutable HashMap where the entries are in no defined order.

    • toLinkedHashMap

      public LinkedHashMap<K,V> toLinkedHashMap()
      Returns a mutable LinkedHashMap where the entries are in the same order as they were added.
      Returns:
      a mutable LinkedHashMap where the entries are in the same order as they were added.

    • toListOrderedMap

      public Map<K,V> toListOrderedMap()
      Returns an immutable Map where the entries are in the same order as they were added. The map may contain nulls. If this ability is not needed, then using ImmutableMap is preferred.
      Returns:
      an immutable Map where the entries are in the same order as they were added.

    • toSortedMap

      public SortedMap<K,V> toSortedMap()
      Returns:
      an immutable SortedMap where the entries are in the natural order of the keys. Note that the key type must implement Comparable.

    • toSortedMap

      public SortedMap<K,V> toSortedMap(Comparator<K> comparator)
      Parameters:
      comparator - used to sort the keys.
      Returns:
      an immutable SortedMap where the entries are in the order defined by the supplied Comparator.

    • toTreeMap

      public TreeMap<K,V> toTreeMap()
      Returns:
      a mutable TreeMap where the entries are in the natural order of the keys. Note that the key type must implement Comparable.

    • toTreeMap

      public TreeMap<K,V> toTreeMap(Comparator<K> comparator)
      Parameters:
      comparator - used to sort the keys.
      Returns:
      a mutable TreeMap where the entries are in the order defined by the supplied Comparator.

    • toMutableMap

      public Map<K,V> toMutableMap()
      Returns:
      a mutable Map where the entries are in no defined order.

    • toFastSortedMap

      public SortedMap<K,V> toFastSortedMap()
      Deprecated.
      Use ImmutableSortedMap directly instead. Since v6.1.
      This returns a guava ImmutableSortedMap, which does not accept nulls. Please use that class directly, instead.
      Returns:
      a fast immutable sorted map
      Throws:
      NullPointerException - if there are any nulls in this builder.
      ClassCastException - if the keys in this builder do not implement Comparable.

    • toFastSortedMap

      public SortedMap<K,V> toFastSortedMap(Comparator<K> comparator)
      Deprecated.
      Use ImmutableSortedMap directly instead. Since v6.1.
      This returns a guava ImmutableSortedMap, which does not accept nulls. Please use that class directly, instead.
      Parameters:
      comparator - for sorting the map
      Returns:
      a fast immutable sorted map
      Throws:
      NullPointerException - if there are any nulls in this builder.
      ClassCastException - if the keys in this builder do not implement Comparable.