Example usage for java.util Collections unmodifiableMap

Introduction

In this page you can find the example usage for java.util Collections unmodifiableMap.

Prototype

public static <K, V> Map<K, V> unmodifiableMap(Map<? extends K, ? extends V> m)

Source Link

Document

Returns an unmodifiable view of the specified map.

Usage

From source file:Main.java

public static <K, V> Map<K, V> copyNullSafeHashMapWithNullValues(Map<? extends K, ? extends V> map) {
    if (map.isEmpty()) {
        return Collections.emptyMap();
    }/*from   ww w .j  a  v  a 2s.c om*/
    return Collections.unmodifiableMap(copyNullSafeMutableHashMapWithNullValues(map));
}

From source file:Main.java

public static <K, V> Map<K, V> immutableMap(Collection<Map.Entry<K, V>> entrySet) {
    Map<K, V> resultMap = new HashMap<K, V>();
    for (Map.Entry<K, V> entry : entrySet) {
        if (entry != null)
            resultMap.put(entry.getKey(), entry.getValue());
    }/*from  w  w  w  .  j  a v  a  2s  .  com*/
    return Collections.unmodifiableMap(resultMap);
}

From source file:Main.java

public static <K, V> Map<K, V> immutableMap(Map<K, V> map) {
    return Collections.unmodifiableMap(new LinkedHashMap<>(map));
}

From source file:Main.java

public static <K extends Object, V extends Object> Map<K, V> unmodifiableMap(
        final Map<? extends K, ? extends V> map) {
    return Collections.unmodifiableMap(map);
}

From source file:Main.java

/**
 * @param entries the <i>final</i> set of entries to add to the newly created <i>unmodifiable</i> map
 * @return an <i>unmodifiable</i> map with all given entries
 *//*from w w w  .j ava2  s.  com*/
public static <K, V> Map<K, V> map(final Entry<K, V>... entries) {
    final HashMap<K, V> map = new HashMap<K, V>(entries.length);
    for (final Entry<K, V> entry : entries) {
        map.put(entry.getKey(), entry.getValue());
    }
    return Collections.unmodifiableMap(map);
}

From source file:Main.java

static <K, V> Map<K, V> getMap(Map<K, V> orig) {
    if (orig == null || orig.size() == 0) {
        return Collections.emptyMap();
    } else if (orig.size() == 1) {
        final Map.Entry<K, V> entry = orig.entrySet().iterator().next();
        return Collections.singletonMap(entry.getKey(), entry.getValue());
    } else {/*from  w  w  w  . j av a2 s  .  c  om*/
        return Collections.unmodifiableMap(new TreeMap<>(orig));
    }
}

From source file:io.github.carlomicieli.footballdb.starter.utils.MapUtils.java

/**
 * Creates a new immutable map from the pair available in the provided stream.
 * @param pairs//from  w  ww .j  av a  2  s  .  c o  m
 * @param <K>
 * @param <V>
 * @return
 */
public static <K, V> Map<K, V> newMap(Stream<ImmutablePair<K, V>> pairs) {
    return Collections
            .unmodifiableMap(pairs.collect(Collectors.toMap(ImmutablePair::getLeft, ImmutablePair::getRight)));
}

From source file:Main.java

/**
 * Returns an unmodifiable view of the specified {@code mapSet}. This
 *  method allows modules to provide users with "read-only" access to
 * {@link Map}, but also to the value {@link Set}.
 *
 * @param <K>/*ww w  . j  ava 2s  . co m*/
 *            the class of the map keys
 * @param <V>
 *            the class of the set values
 * @param mapSet
 *            the {@link Map} of {@link Set} for which an unmodifiable view
 *            is to be returned
 * @return an unmodifiable view of the specified map.
 *
 * @see Collections#unmodifiableMap(Map)
 * @see Collections#unmodifiableSet(Set)
 * @since 4.2
 */
@Nonnull
public static <K, V> Map<K, Set<V>> unmodifiableMapSet(@Nullable final Map<K, Set<V>> mapSet) {
    if (mapSet == null) {
        return Collections.emptyMap();
    }

    for (final Map.Entry<K, Set<V>> entry : mapSet.entrySet()) {
        final K key = entry.getKey();
        final Set<V> value = entry.getValue();

        mapSet.replace(key, Collections.unmodifiableSet(value));
    }

    return Collections.unmodifiableMap(mapSet);
}

From source file:Main.java

/**
 * Make a list map immutable.//from  w  w  w  . j  a  v  a  2  s.  c o m
 *
 * @param listMap
 *            the list map in input.
 * @return the immutable list map.
 */
public static <C, E> Map<C, List<E>> makeListMapImmutable(Map<C, List<E>> listMap) {
    for (C key : listMap.keySet()) {
        listMap.put(key, Collections.unmodifiableList(listMap.get(key)));
    }

    return Collections.unmodifiableMap(listMap);
}

From source file:Main.java

/**
 * Functions as per {@link Collections#unmodifiableMap(Map)} with the exception that if the
 * given map is null, this method will return an unmodifiable empty map as per
 * {@link Collections#emptyMap()}.//from  w  ww .  j a va2s  . c om
 * 
 * @param map the map for which an unmodifiable view is to be returned
 * @return an unmodifiable view of the specified set, or an unmodifiable empty set if the given
 *         set is null
 */
public static <K, V> Map<K, V> unmodifiableMapNullSafe(Map<? extends K, ? extends V> map) {
    if (map == null) {
        return Collections.emptyMap();
    }
    return Collections.unmodifiableMap(map);
}