Example usage for java.util Collection getClass

Introduction

In this page you can find the example usage for java.util Collection getClass.

Prototype

@HotSpotIntrinsicCandidate
public final native Class<?> getClass();

Source Link

Document

Returns the runtime class of this Object .

Usage

From source file:Main.java

@SuppressWarnings("rawtypes")
public static void printInterfaceChecks(Collection c) {
    System.out.println(c.getClass().getName() + "  Implememnts RandomAccess?  " + (c instanceof RandomAccess));
    System.out.println(c.getClass().getName() + "  Implememnts Serializable?  " + (c instanceof Serializable));
    System.out.println(c.getClass().getName() + "  Implememnts cloneable?  " + (c instanceof Cloneable));
}

From source file:Main.java

/**
 * Used to determine immutability of a collection to pass the test #6 :)
 * @param c - a collection/*from   ww  w.jav a 2  s  . c  o m*/
 * @return {@code true} if this collection is one of standard immutable collections
 */
public static boolean isImmutable(Collection<?> c) {
    String className = c.getClass().getName();
    return unmodifiableCollectionClassNamePattern.matcher(className).matches();
}

From source file:Main.java

private static <A, B> Collection<A> buildFrom(Collection<B> as) {
    try {// ww  w .j a v a  2  s .  c  o  m
        return as.getClass().newInstance();
    } catch (Exception e) {
        throw new IllegalArgumentException("Type " + as.getClass() + " needs a parameterless constructor");
    }
}

From source file:Main.java

private static <T> Collection<T> newCollection(Collection<T> coll) {
    try {//from w  w  w .ja v  a2s  .  com
        Class cl = coll.getClass();
        Constructor con = cl.getConstructor(new Class[0]);
        return (Collection<T>) con.newInstance(new Object[0]);
    } catch (Exception e) {
        if (coll instanceof List)
            return new LinkedList<T>();
        if (coll instanceof Set)
            return new HashSet<T>();
        throw new RuntimeException("Cannot handle this collection");
    }
}

From source file:Main.java

/**
 * Creates a new empty instance of the provided collection
 * /*from ww  w.  j a v a 2s  .c  om*/
 * @param <T>
 * @param in
 * @return
 */
public static <T> Collection<T> createEmpty(Collection<?> in) {
    Class<?> originalClass = in.getClass();
    try {
        Constructor<?> originalConstructor = originalClass.getConstructor(new Class[0]);
        return (Collection<T>) originalConstructor.newInstance(new Object[0]);
    } catch (IllegalArgumentException e) {
    } catch (InstantiationException e) {
    } catch (IllegalAccessException e) {
    } catch (InvocationTargetException e) {
    } catch (SecurityException e) {
    } catch (NoSuchMethodException e) {
    } finally {
        return null;
    }
}

From source file:Main.java

private static Collection getEmpty(Collection collection) {
    try {//from  ww  w . ja  v  a  2  s .c om
        return (Collection) collection.getClass().newInstance();
    } catch (Exception e) {
        if (collection instanceof List) {
            return new ArrayList();
        } else {
            return new HashSet();
        }
    }
}

From source file:Main.java

/**
 * Returns a filtered copy of the collection <code>coll</code>.
 *
 * @param coll the collection to filter.
 * @param p the predicate to filter by./*from   ww  w . java  2 s .  c o m*/
 * @return a new collection.
 */

/*public static <T> Collection<T> filter(Collection<T> coll, Predicate<T> p){
Collection<T> c2 = newCollection(coll);
for(T obj: coll)
    if(p.apply(obj))
        c2.add(obj);
return c2;
}*/

private static <T> Collection<T> cloneCollection(Collection<T> coll) {
    try {
        Class cl = coll.getClass();
        Constructor con = cl.getConstructor(new Class[] { Collection.class });
        return (Collection<T>) con.newInstance(new Object[] { coll });
    } catch (Exception e) {
        if (coll instanceof List)
            return new LinkedList<T>(coll);
        if (coll instanceof Set)
            return new HashSet<T>(coll);
        throw new RuntimeException("Cannot handle this collection");
    }
}

From source file:Main.java

/**
 * Create and answer a collection that is the same type, or the closest
 * equivalent of col./*from   w  w w. j a v  a2s.c  o m*/
 * 
 * @param col
 * @return
 */
public static Collection createCollection(Collection col) {
    Collection answer;
    try {
        answer = (Collection) col.getClass().newInstance();
    } catch (Exception e) {
        if (col instanceof List) {
            answer = new ArrayList();
        } else if (col instanceof SortedSet) {
            answer = new TreeSet();
        } else if (col instanceof Set) {
            answer = new HashSet();
        } else {
            answer = new ArrayList(); // should this throw an exception?
        }
    }
    return answer;
}

From source file:Main.java

@SuppressWarnings("unchecked")
public static <T> T[] toArray(Collection<T> c) {
    if (c == null) {
        return null;
    } else {/*from w  w  w  .j a v a2s  .  co m*/
        T[] result = (T[]) Array.newInstance(c.getClass().getComponentType(), c.size());
        int i = 0;
        for (T r : c) {
            result[i] = r;
            i++;
        }
        return result;
    }
}

From source file:therian.operator.immutablecheck.DefaultImmutableChecker.java

private static void addTypeTo(final Set<Class<?>> target, final Collection<?> coll) {
    addImmutableTypeTo(target, coll.getClass());
    addImmutableTypeTo(target, coll.iterator().getClass());
}