/****************************************************************
 * 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.james.mailbox.store;

import org.apache.james.mailbox.MailboxSession;
import org.apache.james.mailbox.MailboxSessionIdGenerator;

public abstract class AbstractMailboxSessionIdGenerator implements MailboxSessionIdGenerator {

    @Override
    public long nextId() {
        long id;
        while ((id = generateNextId()) == MailboxSession.SYSTEM_SESSION_ID) {
            // loop till the id is not 0L
            //
            // See also MAILBOX-149
        }
        return id;
    }
    
    
    protected abstract long generateNextId();
    

}

/****************************************************************
 * 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.james.mailbox.store;

import org.apache.james.mailbox.MailboxSession;
import org.apache.james.mailbox.MailboxSessionIdGenerator;

public abstract class AbstractMailboxSessionIdGenerator implements MailboxSessionIdGenerator {

    @Override
    public long nextId() {
        long id;
        while ((id = generateNextId()) == MailboxSession.SYSTEM_SESSION_ID) {
            // loop till the id is not 0L
            //
            // See also MAILBOX-149
        }
        return id;
    }
    
    
    /**
     * Generate the next id to use
     * 
     * 
     * @return id
     */
    protected abstract long generateNextId();
    

}

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