UniqueId.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.catalina.tribes;

import java.io.Serializable;

import org.apache.catalina.tribes.util.Arrays;

/**
 * Represents a globally unique Id.
 */
public final class UniqueId implements Serializable{
    private static final long serialVersionUID = 1L;

    final byte[] id;

    public UniqueId() {
        this(null);
    }

    public UniqueId(byte[] id) {
        this.id = id;
    }

    public UniqueId(byte[] id, int offset, int length) {
        this.id = new byte[length];
        System.arraycopy(id,offset,this.id,0,length);
    }

    @Override
    public int hashCode() {
        if ( id == null ) {
            return 0;
        }
        return Arrays.hashCode(id);
    }

    @Override
    public boolean equals(Object other) {
        boolean result = (other instanceof UniqueId);
        if ( result ) {
            UniqueId uid = (UniqueId)other;
            if ( this.id == null && uid.id == null ) {
                result = true;
            } else if ( this.id == null && uid.id != null ) {
                result = false;
            } else if ( this.id != null && uid.id == null ) {
                result = false;
            } else {
                result = Arrays.equals(this.id,uid.id);
            }
        }//end if
        return result;
    }

    public byte[] getBytes() {
        return id;
    }

    @Override
    public String toString() {
        return "UniqueId" + Arrays.toString(id);
    }

}