source: other-projects/trunk/gs3-release-maker/apache-ant-1.6.5/src/main/org/apache/tools/zip/ZipLong.java@ 14627

/*
 * Copyright  2001-2002,2004-2005 The Apache Software Foundation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 */

package org.apache.tools.zip;

/**
 * Utility class that represents a four byte integer with conversion
 * rules for the big endian byte order of ZIP files.
 *
 */
public final class ZipLong implements Cloneable {

    private long value;

    /**
     * Create instance from a number.
     *
     * @since 1.1
     */
    public ZipLong(long value) {
        this.value = value;
    }

    /**
     * Create instance from bytes.
     *
     * @since 1.1
     */
    public ZipLong (byte[] bytes) {
        this(bytes, 0);
    }

    /**
     * Create instance from the four bytes starting at offset.
     *
     * @since 1.1
     */
    public ZipLong (byte[] bytes, int offset) {
        value = (bytes[offset + 3] << 24) & 0xFF000000L;
        value += (bytes[offset + 2] << 16) & 0xFF0000;
        value += (bytes[offset + 1] << 8) & 0xFF00;
        value += (bytes[offset] & 0xFF);
    }

    /**
     * Get value as two bytes in big endian byte order.
     *
     * @since 1.1
     */
    public byte[] getBytes() {
        byte[] result = new byte[4];
        result[0] = (byte) ((value & 0xFF));
        result[1] = (byte) ((value & 0xFF00) >> 8);
        result[2] = (byte) ((value & 0xFF0000) >> 16);
        result[3] = (byte) ((value & 0xFF000000l) >> 24);
        return result;
    }

    /**
     * Get value as Java int.
     *
     * @since 1.1
     */
    public long getValue() {
        return value;
    }

    /**
     * Override to make two instances with same value equal.
     *
     * @since 1.1
     */
    public boolean equals(Object o) {
        if (o == null || !(o instanceof ZipLong)) {
            return false;
        }
        return value == ((ZipLong) o).getValue();
    }

    /**
     * Override to make two instances with same value equal.
     *
     * @since 1.1
     */
    public int hashCode() {
        return (int) value;
    }
}