recodequeue.java

这是有关于一个视频自动压缩系统的java+xml构建的代码

package autoencodeinfinit.QueueProcess;

import java.util.Collection;
import java.util.Iterator;
import autoencodeinfinit.XMLProcess.XMLProcess;
import org.w3c.dom.Element;
import org.w3c.dom.Node;

/**
 * create a queue with its basically functions and provide parameter change function from the data of 
 * XML
 * @author ulysess
 */
public class ReCodeQueue extends java.util.AbstractQueue {
    private QueueEntity first = null , last = null , temp = null;
    private int maxlength = 30 , length = 0;
    private String statusxml = null;
    
    /**
     * Add queue entity toadd into the queue by use the method offer() , if offer()
     * return true then return true otherwise throw the IllegalStateException.
     * this method is add according the defination of the class java.util.AbstractQueue
     * recommend use the offer method to add entity  
     * @param toadd : the QueueEntity to be added to the last of the queue
     * @return only return true while offer method return true
     */
    public boolean add(QueueEntity toadd) {
        if ( this.offer(toadd) ) {
            return true;
        } 
        else {
            throw new java.lang.IllegalStateException("Can't add Queue Entity into the queue") ;
        }
    }
    
    /**
     * Add queue entity to the last of the queue if possible
     * @param e : the QueueEntity to be added to the last of the queue 
     * @return only when the queue is full or toadd is null this method will return false
     */
    public boolean offer(Object e) {
        if(e instanceof QueueEntity) {
            QueueEntity toadd =(QueueEntity) e;
            if (first == null && toadd != null) {
                first = toadd;
                last = toadd;
                this.length += 1;
                this.fresh();
                return true;
            } else if (this.length < this.maxlength && toadd != null ){
                last.setNext(toadd);
                last = toadd;
                this.length += 1;
                this.fresh();
                return true;
            } else {
                return false;
            }
        }
        else {
            throw new java.lang.IllegalStateException("Insert a object which is't instanceof QueueEntity");
        }
                
    }

    /**
     * return the first entity of the queue and remove it from the queue , if the queue is empty throw a exception
     * @return
     */
    public QueueEntity remove() {
        if (this.first != null) {
            this.temp  = this.first;
            this.first = this.first.getNext();
            this.length -=1;
            this.fresh();
            return temp;
        }
        else {
            throw new java.lang.IllegalStateException("Can remove entity from empty queue");
        }
    }

    /**
     * Return the first entity of the queue and remove if from the queue ,if the queue is empty return null;
     * @return the first entity of the queue,if queue is empty return null
     */
    public QueueEntity poll() {
        if (this.first != null) {
            this.temp  = this.first;
            this.first = this.first.getNext();
            this.length -= 1;
            this.fresh();
            return temp;
        }
        else {
            return null;
        }
    }

    /**
     * return the first entity of the queue,if the queue is empty ,throw a exception
     * @return
     */
    public QueueEntity element() {
        if (this.first != null) {
            return this.first;
        }
        else {
            throw new java.lang.IllegalStateException("The queue is empty");
        }
    }

    /**
     * return the first entity of the queue.
     * @return
     */
    public QueueEntity peek() {
        return this.first;
    }

    /**
     * move the queue entity in the index number orginal to the index number object
     * @param orginal
     * @param object
     * @return
     */
    public boolean jumpQueue(int orginal , int object){
        if( orginal > this.length || object > this.length || orginal*object < 0) {
            return false;
        }
        QueueEntity temp1 = this.first , temp2 = first , temp3 = null;
        int count = 1;
        for(; count == orginal - 2  ; count++ ) {
            temp1 = temp1.getNext();
        }
        
        for(count = 0 ; count == object - 2 ; count++){
            temp2 = temp2.getNext();
        }
        temp3=temp1;
        temp1.setNext(temp1.getNext().getNext());
        temp3.getNext().setNext(temp2.getNext());
        temp2.setNext(temp3.getNext());
        return true;
    }
    
    /**
     * return the length of the queue 
     * @return
     */
    public int size() {
        return this.length;
    }

    /**
     * check if the queue is empty
     * @return
     */
    public boolean isEmpty() {
        return (this.first == null);
    }

    /**
     * check if this queue inclue the entity qe 
     * @param qe
     * @return
     */
    public boolean contains(QueueEntity qe) {
        for(QueueEntity temp = first ; temp != null ; temp=temp.getNext()){
            if (qe.getIdentity() == temp.getIdentity() ) {
                return true;
            }
        }
        return false;
    }

    /**
     * not implemented yet;
     * @return
     */
    public Iterator iterator() {
        throw new UnsupportedOperationException("Not supported yet.");
    }

     /**
     * not implemented yet;
     * @return
     */
    public Object[] toArray() {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    /**
     * not implemented yet;
     * @return
     */    
    public Object[] toArray(Object[] a) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    /**
     * remove the specific index queue entity
     * @param index : the index number of the queue
     * @return
     */
    public boolean remove(int index) {
        int count =1;
        QueueEntity obj = this.first;
        if (index > this.length || index > this.maxlength ) {
            return false;
        }
        for( ; count == index - 1 ; count++) {
            obj = obj.getNext();
        }
        
        obj.setNext(obj.getNext().getNext());
        this.fresh();
        return true;
        
        
    }

    /**
     * not implemented yet;
     * @return
     */ 
    public boolean containsAll(Collection c) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    /**
     * not implemented yet;
     * @return
     */ 
    public boolean addAll(Collection c) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    /**
     * not implemented yet;
     * @return
     */ 
    public boolean removeAll(Collection c) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    /**
     * not implemented yet;
     * @return
     */ 
    public boolean retainAll(Collection c) {
        throw new UnsupportedOperationException("Not supported yet.");
    }

    /**
     * set empty of this queue
     */
    public void clear() {
        this.first=this.last=null;
    }
    
    /**
     * fresh the queue information in the xml document
     */
    public void fresh() {
        
    }
    
    public void writeQueueStatus(String add) {
        XMLProcess statxmlprocess = null;
        if(add != null && this.statusxml != null) {
            statxmlprocess = XMLProcess.CreateXMLFile(add);
        } else {
            statxmlprocess = new XMLProcess(add);
        }
        
        
        
    }
    
    public void writeQueueStatus() {
        this.writeQueueStatus(this.statusxml);
    }    
    
    private void createStatus(XMLProcess xmlnode) {
        QueueEntity iter = this.first;
        for (int i = 0; i < this.length ; i++) {
            Element insert = xmlnode.insertNodeIn(xmlnode.getRoot(), "Queue Entities" , null);
            for(int cut = 1 ; cut < 5 ; cut ++) {
                 xmlnode.insertNodeIn(insert, "Index", java.lang.String.valueOf(i));
                 xmlnode.insertNodeIn(insert, "Input Address", iter.getInputAdd());
                 xmlnode.insertNodeIn(insert, "Output", iter.getOutputAdd());
                 xmlnode.insertNodeIn(insert, "Parameter", iter.toMencoderParameter());
                 xmlnode.insertNodeIn(insert, "Movie Information", "");
                 xmlnode.insertNodeIn(insert, "Index", java.lang.String.valueOf(i));
                 
            }
            
        }
       
    }
}