nodedeletecommand.java

来自「对eclipse gef进行封装,可以生成图形化编辑器」· Java 代码 · 共 235 行

/*******************************************************************************
 * $Header: /cvsroot/EOS6/work_dir/niegy/com.primeton.studio.gef.ui/src/com/primeton/studio/gef/ui/commands/NodeDeleteCommand.java,v 1.5 2006/12/30 02:45:04 niegy Exp $
 * $Revision: 1.5 $
 * $Date: 2006/12/30 02:45:04 $
 *
 *==============================================================================
 *
 * Copyright (c) 2001-2006 Primeton Technologies, Ltd.
 * All rights reserved. 
 * 
 * Created on 2006-9-28
 *******************************************************************************/



package com.primeton.studio.gef.ui.commands;

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.eclipse.gef.commands.Command;
import org.eclipse.ui.PlatformUI;

import com.primeton.studio.gef.core.Node;
import com.primeton.studio.gef.core.Connection;
import com.primeton.studio.gef.core.Diagram;
import com.primeton.studio.gef.core.NodeElement;
import com.primeton.studio.gef.core.NodeElementLabel;

/**
 * TODO此处填写 class 信息
 *
 * @author niegy (mailto:[e-mail])
 */
/*
 * 修改历史
 * $Log: NodeDeleteCommand.java,v $
 * Revision 1.5  2006/12/30 02:45:04  niegy
 * 重构代码
 *
 * Revision 1.4  2006/12/12 08:26:39  niegy
 * 重构代码,实现一般图元的编辑框
 *
 * Revision 1.3  2006/12/05 05:18:59  niegy
 * 修改模型，增加连线的扩展点
 *
 * Revision 1.2  2006/11/18 12:13:53  niegy
 * 增加容器模型
 *
 * Revision 1.1  2006/11/17 03:15:13  niegy
 * create
 * 
 */
public class NodeDeleteCommand extends Command {
	/** Shape to remove. */
	private final NodeElement child;
	
	/** ShapeDiagram to remove from. */
	private final Node parent;
	/** Holds a copy of the outgoing connections of child. */
	private List sourceConnections = new ArrayList();
	/** Holds a copy of the incoming connections of child. */
	private List targetConnections = new ArrayList();
	/** True, if child was removed from its parent. */
	private boolean wasRemoved;
	
	/**
	 * Create a command that will remove the shape from its parent.
	 * @param parent the ShapesDiagram containing the child
	 * @param child    the Shape to remove
	 * @throws IllegalArgumentException if any parameter is null
	 */
	public NodeDeleteCommand(Node parent, NodeElement child) {
		if (parent == null || child == null) {
			throw new IllegalArgumentException();
		}
		setLabel("node deletion");
		this.parent = parent;
		this.child = child;
	}
	
	/**
	 * Reconnects a List of Connections with their previous endpoints.
	 * @param connections a non-null List of connections
	 */
	private void addConnections(List connections) {
		for (Iterator iter = connections.iterator(); iter.hasNext();) {
            EdgeEntry entry = (EdgeEntry) iter.next();
            Connection conn = entry.getLine();
			conn.getSourceNode().getSourceConnections().add(conn);
			conn.getTargetNode().getTargetConnections().add(conn);
		}
	}
	
	/* (non-Javadoc)
	 * @see org.eclipse.gef.commands.Command#canUndo()
	 */
	public boolean canUndo() {
		return wasRemoved;
	}
	
	
	/* (non-Javadoc)
	 * @see org.eclipse.gef.commands.Command#canExecute()
	 */
	public boolean canExecute() {
		// TODO Auto-generated method stub
		if(child instanceof NodeElementLabel)
			return false;
		else
			return super.canExecute();
	}

	/* (non-Javadoc)
	 * @see org.eclipse.gef.commands.Command#execute()
	 */
	public void execute() {
		// store a copy of incoming & outgoing connections before proceeding 
//        saveConnect(child.getSourceConnections(),sourceConnections);
//        saveConnect(child.getTargetConnections(),targetConnections);
		saveConnect(child); 
		redo();
	}
	
    private void saveConnect(NodeElement nodeElement){
    	List sourceList = nodeElement.getSourceConnections();
        for (Iterator iter = sourceList.iterator(); iter.hasNext();) {
            Connection element = (Connection) iter.next();
            EdgeEntry entry = new EdgeEntry(element);
            sourceConnections.add(entry);
        }
        
        List targetList = nodeElement.getTargetConnections();
        for (Iterator iter = targetList.iterator(); iter.hasNext();) {
            Connection element = (Connection) iter.next();
            EdgeEntry entry = new EdgeEntry(element);
            targetConnections.add(entry);
        }
        
        for (Iterator iter = nodeElement.getNodes().iterator(); iter.hasNext();) {
			NodeElement childNode = (NodeElement) iter.next();
			saveConnect(childNode);
		}
    }
    
	/* (non-Javadoc)
	 * @see org.eclipse.gef.commands.Command#redo()
	 */
	public void redo() {
		// remove the child and disconnect its connections
		wasRemoved = parent.getNodes().contains(child);
		if (wasRemoved) {		    
//			removeConnections(child.getSourceConnections());
//			removeConnections(child.getTargetConnections());
			removeConnections(child);
			delNodelabel();
			parent.getNodes().remove(child);
		}
	}
	
	private void delNodelabel(){
		if(child.getNodeLabel() != null){
			parent.getNodes().remove(child.getNodeLabel());
		}
	}
	
	private void addNodelabel(){
		if(child.getNodeLabel() != null){
			parent.getNodes().add(child.getNodeLabel());
		}
	}
	
	/**
	 * Disconnects a List of Connections from their endpoints.
	 * @param connections a non-null List of connections
	 */
	private void removeConnections(NodeElement nodeElement) {
		List sourceConnections = nodeElement.getSourceConnections();
		for (int i = sourceConnections.size()-1; i >= 0; i--) {
            Connection conn = (Connection) sourceConnections.get(i);
			conn.getSourceNode().getSourceConnections().remove(conn);
			conn.getTargetNode().getTargetConnections().remove(conn);
		}
		
		List targetConnections = nodeElement.getTargetConnections();
		for (int i = targetConnections.size()-1; i >= 0; i--) {
            Connection conn = (Connection) targetConnections.get(i);
			conn.getSourceNode().getSourceConnections().remove(conn);
			conn.getTargetNode().getTargetConnections().remove(conn);
		}
		
		for (Iterator iter = nodeElement.getNodes().iterator(); iter.hasNext();) {
			NodeElement childNode = (NodeElement) iter.next();
			removeConnections(childNode);
		}
	}
	
	/* (non-Javadoc)
	 * @see org.eclipse.gef.commands.Command#undo()
	 */
	public void undo() {
		// add the child and reconnect its connections
		try{
			addConnections(sourceConnections);
			addConnections(targetConnections);			
			if (!parent.getNodes().add(child)) {
				removeConnections(child);	
			}else{
				addNodelabel();
			}
		}
		catch(Exception e){
			e.printStackTrace();
		}
		
	}
    
    private class EdgeEntry {
        private NodeElement source;
        private NodeElement target;
        private Connection edge;
        
        public EdgeEntry( Connection edge ) {
            target = edge.getTargetNode();
            source = edge.getSourceNode();
            this.edge = edge;
        }
        
        public Connection getLine(){
            return edge;
        }
        
    }
}