com.google.common.collect

Class ImmutableMap.Builder<K,V>

  • Direct Known Subclasses:
    ImmutableBiMap.Builder, ImmutableSortedMap.Builder
    Enclosing class:
    ImmutableMap < K , V> 

    public static class ImmutableMap.Builder<K,V>
extends Object
    A builder for creating immutable map instances, especially public static final maps ("constant maps"). Example: 
        static final ImmutableMap<String, Integer> WORD_TO_INT = new ImmutableMap.Builder<String, Integer>() .put("one", 1) .put("two", 2) .put("three", 3) .build();

    For small immutable maps, the ImmutableMap.of() methods are even more convenient.

    Builder instances can be reused - it is safe to call build() multiple times to build multiple maps in series. Each map is a superset of the maps created before it.

    Since:
    2.0

    • Constructor Detail

      • Builder

        public Builder()
        Creates a new builder. The returned builder is equivalent to the builder generated by ImmutableMap.builder().

    • Method Detail

      • put

        public ImmutableMap.Builder<K,V> put(K key,
                                     V value)
        Associates key with value in the built map. Duplicate keys are not allowed, and will cause build() to fail.

      • put

        public ImmutableMap.Builder<K,V> put(Map.Entry<? extends K,? extends V> entry)
        Adds the given entry to the map, making it immutable if necessary. Duplicate keys are not allowed, and will cause build() to fail.
        Since:
        11.0

      • putAll

        public ImmutableMap.Builder<K,V> putAll(Map<? extends K,? extends V> map)
        Associates all of the given map's keys and values in the built map. Duplicate keys are not allowed, and will cause build() to fail.
        Throws:
        NullPointerException - if any key or value in map is null

      • orderEntriesByValue

        @Beta
public ImmutableMap.Builder<K,V> orderEntriesByValue(Comparator<? super V> valueComparator)
        Configures this Builder to order entries by value according to the specified comparator.

        The sort order is stable, that is, if two entries have values that compare as equivalent, the entry that was inserted first will be first in the built map's iteration order.

        Throws:
        IllegalStateException - if this method was already called
        Since:
        19.0