jfimage.java

来自「用Java开发的、实现类似Visio功能的应用程序源码」· Java 代码 · 共 674 行 · 第 1/2 页

        		
            	InputStream in = getClass().getResourceAsStream(imageFile); 
            	if (in == null) { 
        		m_lastError	="Image file: "+imageFile+" not found!";
                	System.err.println(m_lastError); 
                	return false;  
            	} 

            	m_buffer = new byte[in.available()]; 
            	in.read(m_buffer); 
            	in.close();

		return loadImageFromBuffer();
        } 
        catch (Exception e) { 
               m_lastError	=e.getMessage();
               System.out.println("Error: "+m_lastError);
               return true;
        } 
        */
   }


   /**
    *   Load an image file to this object.
    * 
    *   @param File A binary image file.
    *
    */ 	
   public boolean loadImage(File imageFile){
	
	try{
		
		FileInputStream stream=new FileInputStream(imageFile);
		m_buffer	=new byte[stream.available()];
		stream.read(m_buffer);
		stream.close();
		stream		=null;
		
		return loadImageFromBuffer();

	}catch(Exception e){
		m_lastError	=e.getMessage();
		m_logger.error("loadImage,File: "+e);
		return false;
	}
    }   

   
   /** load image from buffer */
   private  boolean loadImageFromBuffer(){
   	try{
		if (m_canvas==null){
			m_lastError	="loadImageFromBuffer : unassigned image observer!";
			m_logger.error(m_lastError);
			return false;
		}

		
		m_image	= null;
            	m_image = Toolkit.getDefaultToolkit().createImage(m_buffer); 

		//Awaiting for completly loaded image.
      	        MediaTracker tracker = new MediaTracker(m_canvas);
      		tracker.addImage(m_image, 0);
      		tracker.waitForID(0);
      		
      		
      		return true;
      		
      	}catch(Exception e){                       
      		m_lastError	=e.getMessage();
      		m_logger.error("loadImageFromBuffer: "+e);

      		return false;
	}
   }

   /** finish loading image 
    *  for loading an image from a buffer, we need to call this method later after loading the binary data
    *  into buffer.
    */
   public  boolean finishLoading(Component canvas){
   	m_canvas	=canvas;
   	return loadImageFromBuffer();
   }


   /**
    *   Set the intial position of this internal label.
    *
    */ 	
   protected void initLabel(){
   	m_label.setParent(this);   	
   	Rect 	rect=getBounds();
   	JFPoint  pos	=rect.getCenter();
   	pos.setY(pos.getY()-rect.getHeight()/2-GeomConst.PICK_OFFSET*5);
   	m_label.setLabelPoint(pos);
   }


   /**
    *   Creates a new AbstractObject of the same class and with the same contents as this object.
    *   This method implements the method defined in AbstractObject.
    * 
    *   @return  A clone of this class.
    *
    */ 	
  protected AbstractObject cloneMe() throws CloneNotSupportedException{
  	return new JFImage();
  }


   /**
    *   Creates a new object of the same class and with the same contents as this object.
    * 
    *   @return  A clone of this instance.
    *
    */ 	
  public Object clone() throws CloneNotSupportedException{
  	try{
  		Object obj =super.clone();
  		if (obj==null){
  			return null;
  		}
  		
  		JFImage img=(JFImage) obj;
  		img.m_canvas	=m_canvas;
  		img.m_buffer	=new byte[m_buffer.length];
  		System.arraycopy(m_buffer,0,img.m_buffer,0,m_buffer.length);
                img.loadImageFromBuffer();
	
  		return img;
  		
	}catch(Exception e){
		throw new CloneNotSupportedException(e.getMessage());
	}
  }

   /**
    *   Returns the hashcode for this Object.
    * 
    *   @return hash code for this Point2D.
    *
    */ 	
  public int hashCode(){
  	return 	super.hashCode() ^ CollectionUtil.getHashCode(m_buffer);
  }


   /**
    *   Determines whether or not two objects are equal. 
    * 
    * 	@param obj  an object to be compared with this object 
    * 
    *   @return true if the object to be compared is an instance of Port and has the same values; false otherwise.
    *
    */ 	
  public boolean equals(Object obj){
      if (!super.equals(obj))
             return false;
             		
      if (obj == this)
             return true;
      if (!(obj instanceof JFImage))
            return false;

      JFImage  img= (JFImage)obj;
      
      return  	CollectionUtil.compareArrays(m_buffer,img.m_buffer);
  }
     

   /**
    *   Append necessary xml child for current element,
    *   this method will be called internally by toDOM.
    * 
    *   @param  element A XML element to append child xml nodes
    *
    *   @param version A file version notification so this object can obey the rules to save data.
    */ 	
  protected void appendChildToDOM(Element element,JFVersion version){
  	if (element==null)
  		return;
  			
  	super.appendChildToDOM(element,version);
    	element.addChild(new Element(XML_IMAGEDATA, Base64.encodeBytes(m_buffer)));
  }


   /**
    *   Extract needed xml child from current element,
    *   this method will be called internally by fromDOM.
    * 
    *   @param  element An element used to extract needed xml child
    *   @param version A file version notification so this object can obey the rules to fetch data.
    *
    */ 	
  protected void extractChildFromDOM(Element element,JFVersion version){


      	if (element==null)
  	  	return;

 
      	super.extractChildFromDOM(element,version);

      	m_buffer	=Base64.decode(Element.getStringValue(element.getChild(XML_IMAGEDATA)));

	if (m_buffer==null){
		m_logger.error("extractChildFromDOM: null image data!");
	}
	//here we have not load the image and create a Image object completely,
	//we need to call a finishLoading method later.
  }

 
   /**
    *   Save this object to a binary stream 
    * 
    *   @param stream An binary output stream
    *
    *   @param version A file version notification so this object can obey the rules to save data.
    *   @exception  java.io.IOException
    *
    */ 	
  public void saveToStream(com.jfimagine.utils.io.JFWriter stream,JFVersion version) throws IOException{
	 super.saveToStream(stream,version);
		
	 int bufSize	=m_buffer.length;	         
         //save length of image buffer
         stream.writeInt(bufSize);
         if (bufSize>0){
         	stream.write(m_buffer,0,bufSize);
         }
  }

   /**
    *   Load object data from a binary stream <br>
    * 
    *   @param stream An binary input stream
    *
    *   @param skipHead Skip head 'TYPE' check, an shape object should always 
    *   has its own shape-type stored, if this shape-type has already been readed,
    *   this loadFromStream should/could not read the type anymore.
    *
    *   @param version A file version notification so this object can obey the rules to fetch data.
    *   @exception  java.io.IOException
    *
    */ 	
  public void loadFromStream(com.jfimagine.utils.io.JFReader stream,boolean skipHead,JFVersion version) throws IOException{
	super.loadFromStream(stream,skipHead,version);

	//load the length of image buffer first
  	int bufSize	=stream.readInt();
  	
  	//load the image data
  	if (bufSize>0){
  		m_buffer	=new byte[bufSize];
  		stream.read(m_buffer,0,bufSize);
		//here we have not load the image and create a Image object completely,
		//we need to call a finishLoading method later.
 	}
     	
  }
 
 
   /**
    *   for loading an image, we need to call this finish loading image method to completely create a new image.
    * 
    *   @param objList An objectList that contains shapes.
    *   @param canvas A component for creating an image object.
    */
  public static boolean finishLoadingImages(ObjectList objList,java.awt.Component canvas){	
	if (objList==null || objList.size()==0 || canvas==null)
		return false;
		

  	Iterator it	=objList.getList().iterator();
  	while (it!=null && it.hasNext()){
  		AbstractObject obj	=(AbstractObject)it.next();
  		finishLoadingImages(obj,canvas);
	}   
	
	return true;
  }


   /**
    *   for loading an image, we need to call this finish loading image method to completely create a new image.
    * 
    *   @param obj An Abstract object.
    *   @param canvas A component for creating an image object.
    */
  public static boolean finishLoadingImages(AbstractObject obj,java.awt.Component canvas){	
	if (obj==null || canvas==null)
		return false;

	if (obj instanceof JFPage){
		JFPage page	=(JFPage)obj;
		return page.finishLoadingImages(canvas);
	}

  	try{
  		AbstractShape aobj	=(AbstractShape)obj;
  		if (aobj instanceof JFImage){
  			JFImage img	=(JFImage)aobj;
  			img.finishLoading(canvas);
  		
  		}else if (aobj instanceof JFGroup){
  			JFGroup g	=(JFGroup)aobj;
  			ObjectList l	=g.getList();  
  			finishLoadingImages(l,canvas);
  		}
  		return true;
  	}catch(Exception e){
  		m_logger.error("finishLoadingImages: "+e);
  		return false;
  	}
  }


   /**
    *   Free the Resource of current object used.<br>
    * 
    *   This is not trying to free the memory that current object used.
    *   It's only used to release some memory that the GC can not work with.
    *
    */ 	
  public void freeResources(){
	m_buffer	=null;
   	m_image		=null;
  }

       
    
}