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A library that encapsulates the repeatable actions of Android Cursors.

There is a newer version: 0.4

package com.venmo.cursor;

import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.LinkedList;

/**
 * Utility class of default implementations for {@link IterableCursor} methods. If Android gets
 * support for Java 8, these can become default methods in the interface.
 */
public final class CursorUtils {

    private CursorUtils() {
        throw new UnsupportedOperationException("Non-instantiable class");
    }

    /**
     * Add each item of this {@link android.database.Cursor} to the {@code collection} parameter.
     * Closes the cursor once completed.
     *
     * @return the same collection as the parameter.
     * @see #consumeToArrayList(com.venmo.cursor.IterableCursor)
     * @see #consumeToLinkedList(com.venmo.cursor.IterableCursor)
     * @see #consumeToLinkedHashSet(com.venmo.cursor.IterableCursor)
     */
    public static > C consumeToCollection(IterableCursor cursor,
            C collection) {
        for (T t : cursor) {
            collection.add(t);
        }
        cursor.close();
        return collection;
    }

    /**
     * Returns an {@link java.util.ArrayList} of the {@link android.database.Cursor} and closes it.
     */
    public static  ArrayList consumeToArrayList(IterableCursor cursor) {
        return consumeToCollection(cursor, new ArrayList(cursor.getCount()));
    }

    /**
     * Returns an {@link java.util.LinkedList} of the {@link android.database.Cursor} and closes
     * it.
     */
    public static  LinkedList consumeToLinkedList(IterableCursor cursor) {
        return consumeToCollection(cursor, new LinkedList());
    }

    /**
     * Returns an {@link java.util.LinkedHashSet} of the {@link android.database.Cursor} and closes
     * it.
     */
    public static  LinkedHashSet consumeToLinkedHashSet(IterableCursor cursor) {
        return consumeToCollection(cursor, new LinkedHashSet(cursor.getCount()));
    }

    public static  T nextDocumentHelper(IterableCursor cursor) {
        T t = cursor.peek();
        cursor.moveToNext();
        return t;
    }

    public static  T previousDocumentHelper(IterableCursor cursor) {
        cursor.moveToPrevious();
        return cursor.peek();
    }
}