Example usage for java.util Collections unmodifiableSet

Introduction

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

Prototype

public static <T> Set<T> unmodifiableSet(Set<? extends T> s)

Source Link

Document

Returns an unmodifiable view of the specified set.

Usage

From source file:Main.java

public static <E> Set<E> intersection(final Set<E> set1, final Set<E> set2) {
    Set<E> set = new HashSet<>(set1);
    set.retainAll(set2);/*from  w  ww. j a v  a 2  s  . c  o  m*/
    return Collections.unmodifiableSet(set);
}

From source file:Main.java

public static <T> Set<T> copyToLinkedHashSet(Collection<? extends T> src) {
    if (src.isEmpty()) {
        return Collections.emptySet();
    }/*www . j  av  a  2  s . c  o m*/

    return Collections.unmodifiableSet(new LinkedHashSet<T>(src));
}

From source file:Main.java

public static <T> Set<T> immutableSet(Collection<? extends T> set) {
    return Collections.unmodifiableSet(set instanceof Set ? (Set<? extends T>) set : new HashSet<T>(set));
}

From source file:Main.java

/** Shortcut for creating a Set collection. Used for the list of required and unbound parameters. */
public static <T2> Set<T2> unmodifiableSet(T2... items) {
    return Collections.unmodifiableSet(new HashSet<T2>(Arrays.asList(items)));
}

From source file:Main.java

@SafeVarargs
public static <V> Set<V> unmodifiableSet(Set<V> s, V... elements) {
    return Collections.unmodifiableSet(toSet(s, elements));
}

From source file:Main.java

public static <T> Set<T> asUnmodifiableSet(T[] a_array)
/*     */ {/*from   w  ww  . java2 s.co  m*/
    /* 318 */if (a_array == null)
    /*     */ {
        /* 320 */return null;
        /*     */}
    /*     */
    /* 324 */List list = Arrays.asList(a_array);
    /* 325 */Set set = new HashSet(list);
    /* 326 */return Collections.unmodifiableSet(set);
    /*     */}

From source file:Main.java

public static <T> Set<T> immutableSet(T... set) {
    if (set == null)
        return Collections.emptySet();
    return Collections.unmodifiableSet(new HashSet<T>(Arrays.asList(set)));
}

From source file:Main.java

public static <T> Set<T> toImmutableSet(Set<T> set) {
    switch (set.size()) {
    case 0:/*from w w w  .  j a  v  a2s  .c om*/
        return Collections.emptySet();
    case 1:
        return Collections.singleton(set.iterator().next());
    default:
        return Collections.unmodifiableSet(set);
    }
}

From source file:Main.java

/**
 * Convert a String to a unmodifiable set of characters.
 * @param str The string to convert/*from w  ww .j av  a  2  s  .  com*/
 * @return A set containing the characters in str. A empty set
 *    is returned if str is null.
 */
public static Set<Character> strToUnmodifiableSet(String str) {
    if (str == null)
        return Collections.emptySet();
    if (str.length() == 1)
        return Collections.singleton(str.charAt(0));
    return Collections.unmodifiableSet(strToSet(str));
}

From source file:Main.java

public static <T> Set<T> unmodifiableSet(Set<? extends T> list) {
    if ((list == null) || (list.isEmpty())) {
        return Collections.emptySet();
    }//from   w w w .j a  v  a 2 s. c  o m
    return Collections.unmodifiableSet(list);
}