tlongarraylist.java

这是一个matlab的java实现。里面有许多内容。请大家慢慢捉摸。

///////////////////////////////////////////////////////////////////////////////
// Copyright (c) 2001, Eric D. Friedman All Rights Reserved.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public
// License as published by the Free Software Foundation; either
// version 2.1 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public
// License along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
///////////////////////////////////////////////////////////////////////////////

package gnu.trove;

import java.io.Serializable;
import java.util.Arrays;
import java.util.Random;

/**
 * A resizable, array-backed list of long primitives.
 *
 * Created: Sat Dec 29 14:21:12 2001
 *
 * @author Eric D. Friedman
 * @version $Id: TLongArrayList.java,v 1.1.1.1 2003/07/14 19:36:04 mccallum Exp $
 */

public class TLongArrayList implements Serializable, Cloneable {

    /** the data of the list */
    protected long[] _data;

    /** the index after the last entry in the list */
    protected int _pos;

    /** the default capacity for new lists */
    protected static final int DEFAULT_CAPACITY = 10;

    /**
     * Creates a new <code>TLongArrayList</code> instance with the
     * default capacity.
     */
    public TLongArrayList() {
        this(DEFAULT_CAPACITY);
    }

    /**
     * Creates a new <code>TLongArrayList</code> instance with the
     * specified capacity.
     *
     * @param capacity an <code>int</code> value
     */
    public TLongArrayList(int capacity) {
        _data = new long[capacity];
        _pos = 0;
    }

    /**
     * Creates a new <code>TLongArrayList</code> instance whose
     * capacity is the greater of the length of <tt>values</tt> and
     * DEFAULT_CAPACITY and whose initial contents are the specified
     * values.
     *
     * @param values an <code>long[]</code> value
     */
    public TLongArrayList(long[] values) {
        this(Math.max(values.length, DEFAULT_CAPACITY));
        add(values);
    }

    // sizing

    /**
     * Grow the internal array as needed to accomodate the specified
     * number of elements.  The size of the array doubles on each
     * resize unless <tt>capacity</tt> requires more than twice the
     * current capacity.
     *
     * @param capacity an <code>int</code> value
     */
    public void ensureCapacity(int capacity) {
        if (capacity > _data.length) {
            int newCap = Math.max(_data.length << 1, capacity);
            long[] tmp = new long[newCap];
            System.arraycopy(_data, 0, tmp, 0, _data.length);
            _data = tmp;
        }
    }

    /**
     * Returns the number of values in the list.
     *
     * @return the number of values in the list.
     */
    public int size() {
        return _pos;
    }

    /**
     * Tests whether this list contains any values.
     *
     * @return true if the list is empty.
     */
    public boolean isEmpty() {
        return _pos == 0;
    }

    /**
     * Sheds any excess capacity above and beyond the current size of
     * the list.
     */
    public void trimToSize() {
        if (_data.length > size()) {
            long[] tmp = new long[size()];
            toNativeArray(tmp, 0, tmp.length);
            _data = tmp;
        }
    }

    // modifying

    /**
     * Adds <tt>val</tt> to the end of the list, growing as needed.
     *
     * @param val an <code>long</code> value
     */
    public void add(long val) {
        ensureCapacity(_pos + 1);
        _data[_pos++] = val;
    }

    /**
     * Adds the values in the array <tt>vals</tt> to the end of the
     * list, in order.
     *
     * @param vals an <code>long[]</code> value
     */
    public void add(long[] vals) {
        add(vals, 0, vals.length);
    }

    /**
     * Adds a subset of the values in the array <tt>vals</tt> to the
     * end of the list, in order.
     *
     * @param vals an <code>long[]</code> value
     * @param offset the offset at which to start copying
     * @param length the number of values to copy.
     */
    public void add(long[] vals, int offset, int length) {
        ensureCapacity(_pos + length);
        System.arraycopy(vals, offset, _data, _pos, length);
        _pos += length;
    }

    /**
     * Inserts <tt>value</tt> into the list at <tt>offset</tt>.  All
     * values including and to the right of <tt>offset</tt> are shifted
     * to the right.
     *
     * @param offset an <code>int</code> value
     * @param value an <code>long</code> value
     */
    public void insert(int offset, long value) {
        if (offset == _pos) {
            add(value);
            return;
        }
        ensureCapacity(_pos + 1);
        // shift right
        System.arraycopy(_data, offset, _data, offset + 1, _pos - offset);
        // insert
        _data[offset] = value;
        _pos++;
    }

    /**
     * Inserts the array of <tt>values</tt> into the list at
     * <tt>offset</tt>.  All values including and to the right of
     * <tt>offset</tt> are shifted to the right.
     *
     * @param offset an <code>int</code> value
     * @param values an <code>long[]</code> value
     */
    public void insert(int offset, long[] values) {
        insert(offset, values, 0, values.length);
    }

    /**
     * Inserts a slice of the array of <tt>values</tt> into the list
     * at <tt>offset</tt>.  All values including and to the right of
     * <tt>offset</tt> are shifted to the right.
     *
     * @param offset an <code>int</code> value
     * @param values an <code>long[]</code> value
     * @param valOffset the offset in the values array at which to
     * start copying.
     * @param len the number of values to copy from the values array
     */
    public void insert(int offset, long[] values, int valOffset, int len) {
        if (offset == _pos) {
            add(values, valOffset, len);
            return;
        }

        ensureCapacity(_pos + len);
        // shift right
        System.arraycopy(_data, offset, _data, offset + len, _pos - offset);
        // insert
        System.arraycopy(values, valOffset, _data, offset, len);
        _pos += len;
    }

    /**
     * Returns the value at the specified offset.
     *
     * @param offset an <code>int</code> value
     * @return an <code>long</code> value
     */
    public long get(int offset) {
        if (offset >= _pos) {
            throw new ArrayIndexOutOfBoundsException(offset);
        }
        return _data[offset];
    }

    /**
     * Returns the value at the specified offset without doing any
     * bounds checking.
     *
     * @param offset an <code>int</code> value
     * @return an <code>long</code> value
     */
    public long getQuick(int offset) {
        return _data[offset];
    }

    /**
     * Sets the value at the specified offset.
     *
     * @param offset an <code>int</code> value
     * @param val an <code>long</code> value
     */
    public void set(int offset, long val) {
        if (offset >= _pos) {
            throw new ArrayIndexOutOfBoundsException(offset);
        }
        _data[offset] = val;
    }

    /**
     * Sets the value at the specified offset and returns the
     * previously stored value.
     *
     * @param offset an <code>int</code> value
     * @param val an <code>long</code> value
     * @return the value previously stored at offset.
     */
    public long getSet(int offset, long val) {
        if (offset >= _pos) {
            throw new ArrayIndexOutOfBoundsException(offset);
        }
        long old = _data[offset];
        _data[offset] = val;
        return old;
    }

    /**
     * Replace the values in the list starting at <tt>offset</tt> with
     * the contents of the <tt>values</tt> array.
     *
     * @param offset the first offset to replace
     * @param values the source of the new values
     */
    public void set(int offset, long[] values) {
        set(offset, values, 0, values.length);
    }

    /**
     * Replace the values in the list starting at <tt>offset</tt> with
     * <tt>length</tt> values from the <tt>values</tt> array, starting
     * at valOffset.
     *
     * @param offset the first offset to replace
     * @param values the source of the new values
     * @param valOffset the first value to copy from the values array
     * @param length the number of values to copy
     */
    public void set(int offset, long[] values, int valOffset, int length) {
        if (offset < 0 || offset + length >= _pos) {
            throw new ArrayIndexOutOfBoundsException(offset);
        }
        System.arraycopy(_data, offset, values, valOffset, length);
    }

    /**
     * Sets the value at the specified offset without doing any bounds
     * checking.
     *
     * @param offset an <code>int</code> value
     * @param val an <code>long</code> value
     */
    public void setQuick(int offset, long val) {
        _data[offset] = val;
    }

    /**
     * Flushes the internal state of the list, resetting the capacity
     * to the default.
     */
    public void clear() {
        clear(DEFAULT_CAPACITY);
    }

    /**
     * Flushes the internal state of the list, setting the capacity of
     * the empty list to <tt>capacity</tt>.
     *
     * @param capacity an <code>int</code> value
     */
    public void clear(int capacity) {
        _data = new long[capacity];
        _pos = 0;
    }

    /**
     * Sets the size of the list to 0, but does not change its
     * capacity.  This method can be used as an alternative to the
     * {@link #clear clear} method if you want to recyle a list without
     * allocating new backing arrays.
     *
     * @see #clear
     */
    public void reset() {
        _pos = 0;
        fill(0);
    }

    /**
     * Sets the size of the list to 0, but does not change its
     * capacity.  This method can be used as an alternative to the
     * {@link #clear clear} method if you want to recyle a list
     * without allocating new backing arrays.  This method differs
     * from {@link #reset reset} in that it does not clear the old
     * values in the backing array.  Thus, it is possible for {@link
     * #getQuick getQuick} to return stale data if this method is used
     * and the caller is careless about bounds checking.
     *
     * @see #reset
     * @see #clear
     * @see #getQuick
     */
    public void resetQuick() {
        _pos = 0;
    }

    /**
     * Removes the value at <tt>offset</tt> from the list.
     *
     * @param offset an <code>int</code> value
     * @return the value previously stored at offset.
     */
    public long remove(int offset) {
        long old = get(offset);
        remove(offset, 1);
        return old;
    }

    /**
     * Removes <tt>length</tt> values from the list, starting at
     * <tt>offset</tt>
     *
     * @param offset an <code>int</code> value
     * @param length an <code>int</code> value
     */
    public void remove(int offset, int length) {
        if (offset < 0 || offset >= _pos) {
            throw new ArrayIndexOutOfBoundsException(offset);
        }

        if (offset == 0) {
            // data at the front
            System.arraycopy(_data, length, _data, 0, _pos - length);
        } else if (_pos - length == offset) {
            // no copy to make, decrementing pos "deletes" values at
            // the end
        } else {
            // data in the middle
            System.arraycopy(_data, offset + length,
                             _data, offset, _pos - (offset + length));
        }
        _pos -= length;
        // no need to clear old values beyond _pos, because this is a
        // primitive collection and 0 takes as much room as any other
        // value
    }

    /**
     * Transform each value in the list using the specified function.
     *
     * @param function a <code>TLongFunction</code> value
     */
    public void transformValues(TLongFunction function) {
        for (int i = _pos; i-- > 0;) {
            _data[i] = function.execute(_data[i]);
        }
    }

    /**
     * Reverse the order of the elements in the list.
     */
    public void reverse() {
        reverse(0, _pos);
    }

    /**
     * Reverse the order of the elements in the range of the list.