Example usage for java.util Collection size

Introduction

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

Prototype

int size();

Source Link

Document

Returns the number of elements in this collection.

Usage

From source file:Main.java

/**
 * Calls the {@link Collection#toArray(Object[])} method constructing array based on the given argument type.
 *
 * @param <E>/*from  w  w  w  .j av a 2 s . co  m*/
 *            the element type
 * @param collection
 *            the collection
 * @param type
 *            the type
 * @return the e[]
 */
@SuppressWarnings("unchecked")
public static <E> E[] toArray(Collection<? extends E> collection, Class<E> type) {
    return collection.toArray((E[]) Array.newInstance(type, collection.size()));
}

From source file:Main.java

public static <ELEMENT> LinkedHashSet<ELEMENT> newLinkedHashSet(Collection<ELEMENT> elements) {
    final LinkedHashSet<ELEMENT> set = newLinkedHashSetSized(elements.size());
    set.addAll(elements);/*from w  w w  .j  av a2 s  . c om*/
    return set;
}

From source file:Main.java

/**
 * @param list/*w  w  w  . j av  a 2  s. c om*/
 * @return the size of the collection or 0 if the collection is null
 */
public static int getSize(Collection<?> collection) {

    if (collection == null) {

        return 0;
    }

    return collection.size();
}

From source file:Main.java

@SuppressWarnings("rawtypes")
public static int sizeOf(Collection collection) {
    if (isEmpty(collection)) {
        return 0;
    }//from  w  w w .  j  a  va 2  s.c o m
    return collection.size();
}

From source file:Main.java

/**
 * Returns the size of the collection if it can be determined to be a collection
 *
 * @param value the collection//  w w w . j  ava  2s.  c  om
 * @return the size, or <tt>null</tt> if not a collection
 */
public static Integer size(Object value) {
    if (value != null) {
        if (value instanceof Collection) {
            Collection<?> collection = (Collection<?>) value;
            return collection.size();
        } else if (value instanceof Map) {
            Map<?, ?> map = (Map<?, ?>) value;
            return map.size();
        } else if (value instanceof Object[]) {
            Object[] array = (Object[]) value;
            return array.length;
        } else if (value.getClass().isArray()) {
            return Array.getLength(value);
        } else if (value instanceof NodeList) {
            NodeList nodeList = (NodeList) value;
            return nodeList.getLength();
        }
    }
    return null;
}

From source file:Main.java

/************************ size ************************************/

public static <T> int nullSafeSize(Collection<T> collection) {
    if (collection == null) {
        return 0;
    }//from www  .  j ava  2s.c o  m
    return collection.size();
}

From source file:Main.java

/**
 * To Array//from  w w w . j  ava2s. co m
 * 
 * @param c
 *            Collection
 * @return T[]
 */
@SuppressWarnings("unchecked")
public static <T> T[] toArray(Collection<T> c) {
    if (c == null) {
        return null;
    }
    return (T[]) c.toArray(new Object[c.size()]);
}

From source file:Main.java

/**
 * Traverse collection//from   ww w . jav  a2 s  . c om
 *
 * @param c
 * @param <T>
 * @return
 */
public static <T> String traverseCollection(Collection<T> c) {
    if (!isEmpty(c)) {
        int len = c.size();
        StringBuilder builder = new StringBuilder(len);
        int i = 0;
        for (T t : c) {
            if (t == null) {
                continue;
            }
            builder.append(t.toString());
            i++;
            if (i < len) {
                builder.append(DELIMITER);
            }
        }
        return builder.toString();
    }
    return null;
}

From source file:Main.java

public static <T> int size(Collection<T> list) {
    if (list == null) {
        return 0;
    }/*from  w ww .  j  a v a  2s. c om*/
    return list.size();
}

From source file:Main.java

public static <T> String join(Collection<T> col, String separator) {
    String ret = "";
    if (col != null && col.size() > 0) {
        for (Object x : col) {
            if (x instanceof String) {
                ret += separator + (String) x;
            } else {
                ret += separator + x.toString();
            }//from w  w w  .j  a v a2s.com
        }
    }
    return ret.replaceFirst(separator, "");

}