jrelation.java

基于java地snmpMIB地访问地实现,已经使用了较长时间.

/*
 * Copyright (c) 2002-2003 UTStarcom, Inc.
 * All rights reserved.
 */
package core.relation.jrelation;

import core.relation.common.Relation;
import core.relation.common.Body;
import core.relation.common.FilterBody;
import core.relation.common.MessageFilter;

import java.util.Iterator;
import java.util.Vector;

/**
 * The JRelation class.
 * observer
 * @author Heter pan
 */
public class JRelation implements Relation {
    Vector children;
    Object cache;
    Body parentBody;
    Vector messages;
    public JRelation() {
        children = new Vector( 1 );
        messages = new Vector( 1 );
    }

    public JRelation( Body aParentBody ) {
        parentBody = aParentBody;
        children = new Vector( 1 );
        messages = new Vector( 1 );
    }

    // set parent and remove all child and messages;
    public void reset( Body aParentBody ) {
        parentBody = aParentBody;
        messages.removeAllElements();
        children.removeAllElements();
    }

    public void removeAllMessages() {
        messages.removeAllElements();
    }

    public void addMessage( Object message ) {
        if ( messages.contains( message ) ) {
            messages.remove( message );
            messages.add( message );
        }
        messages.add( message );
    }

    public void removeMessage( Object message ) {
        messages.remove( message );
    }


    // for message cache, used with addMessage and removeMessage
    public void send() {

        Iterator i = children.iterator();

        while ( i.hasNext() ) {
            Body body = ( Body ) i.next();
            if ( body instanceof FilterBody ) {

                MessageFilter mf = ( ( FilterBody ) body ).getFilter();
                Iterator itor = messages.iterator();
                while ( itor.hasNext() ) {
                    System.out.println( "ok" );
                    Object message = itor.next();
                    if ( mf.filter( message ) ) body.receive( message );
                }

            } else {
                Iterator itr = messages.iterator();
                while ( itr.hasNext() ) {
                    body.receive( itr.next() );
                }

            }
        }
    }

    public void readyReceive( boolean b ) {
        Iterator i = children.iterator();
        while ( i.hasNext() ) {
            Body body = ( Body ) i.next();
            if ( body instanceof FilterBody ) {
                ( ( FilterBody ) body ).readyReceive( b );
           }
        }
    }

    public void send( boolean filter ) {
        if ( filter ) {
            send();
            return;
        }
        Iterator i = children.iterator();
        while ( i.hasNext() ) {
            Body body = ( Body ) i.next();
            if ( body instanceof FilterBody ) {
                Iterator itor = messages.iterator();
                while ( itor.hasNext() ) {
                    System.out.println( "ok" );
                    Object message = itor.next();
                    body.receive( message );
                }

            } else {
                Iterator itr = messages.iterator();
                while ( itr.hasNext() ) {
                    body.receive( itr.next() );
                }

            }
        }

    }

    public void sendCache() {
        if ( cache == null ) return;
        Iterator i = children.iterator();

        while ( i.hasNext() ) {
            Body body = ( Body ) i.next();
            if ( body instanceof FilterBody ) {
                MessageFilter mf = ( ( FilterBody ) body ).getFilter();
                if ( mf.filter( cache ) ) body.receive( cache );
            } else {

                body.receive( cache );


            }
        }
    }

    public void sendAndSave( Object message ) {
        Iterator i = children.iterator();
        while ( i.hasNext() ) {
            Body e = ( Body ) i.next();
            if ( e instanceof FilterBody ) {
                if ( ( ( FilterBody ) e ).getFilter().filter( message ) )
                    e.receive( message );
            } else
                e.receive( message );
        }
        cache = message;
    }

    public void send( Object message ) {
        Iterator i = children.iterator();
        while ( i.hasNext() ) {
            Body e = ( Body ) i.next();
            if ( e instanceof FilterBody ) {
                if ( ( ( FilterBody ) e ).isReadyReceive() )
                    if ( ( ( FilterBody ) e ).getFilter().filter( message ) )
                        e.receive( message );
            } else
                e.receive( message );
        }

    }
    public void sendAndCache( Object message ) {
        Iterator i = children.iterator();
        while ( i.hasNext() ) {
            Body e = ( Body ) i.next();
            if ( e instanceof FilterBody ) {
                if ( ( ( FilterBody ) e ).isReadyReceive() )
                    if ( ( ( FilterBody ) e ).getFilter().filter( message ) )
                        e.receive( message );
            } else
                e.receive( message );
        }
       cache = message;
    }
    public void send( Object message, boolean filter ) {
        if ( filter ) send( message );
        Iterator i = children.iterator();
        while ( i.hasNext() ) {
            Body e = ( Body ) i.next();
            if ( e instanceof FilterBody ) {
                if ( ( ( FilterBody ) e ).isReadyReceive() )
                    e.receive( message );
            } else
                e.receive( message );
        }

    }

    public void addChildBody( Body b ) {
        children.add( b );
    }

    public void removeChildBody( Body b ) {
        children.remove( b );
    }

    public void removeAllChildren() {
        children.removeAllElements();
    }

}