视图开发-数据保存

在模型中添加保存和加载元素的代码，将数组adress中元素保存到Adress.xml文件

public class AddressManager implements IPropertyChangeListener{
	private static final String TAG_ADDRESSES = "Addresses";
	private static final String TAG_ADDRESS = "AddressItem";
	private static final String TAG_NAME = "name";
	private static final String TAG_CATEGORY = "category";

public void saveAddresses(){
		if(addresses == null)
			return;
		XMLMemento memento = XMLMemento.createWriteRoot(TAG_ADDRESSES);
		saveAddresses(memento);
		FileWriter writer = null;		
		try{
			writer = new FileWriter(getAddressesFile());
			memento.save(writer);
		}catch(IOException e){
			//to be added
		}finally{
			try{
				if(writer != null)
					writer.close();
			}catch(IOException e){
				//to be added
			}
		}
	}
	public void saveAddresses(IMemento memento){
		Iterator iter = addresses.iterator();
		while(iter.hasNext()){
			AddressItem item = (AddressItem)iter.next();
			
			IMemento child = memento.createChild(TAG_ADDRESS);
			child.putString(TAG_NAME, item.getName());
			child.putString(TAG_CATEGORY, item.getCategory().getCategoryName());
		}
	}

private File getAddressesFile() {
		IPath path=Activator.getDefault().getStateLocation();
		return 
			path.append("Addresses.xml").toFile();
	}


//从文件读取元素

private void loadAddresses(){
FileReader reader = null;
		try{
			reader = new FileReader(getAddressesFile());
			loadAddresses(XMLMemento.createReadRoot(reader));
		}catch(FileNotFoundException e)
		{
			//to be added
		}catch(Exception e)
		{
			//to be added
		}finally{
			try{
				if(reader != null)
					reader.close();
			}
			catch(IOException e){
				//to be added
			}
		}
		/*end*/
	}
private void loadAddresses(XMLMemento memento)
	{
		IMemento[] children = memento.getChildren(TAG_ADDRESS);
		for(int i = 0; i < children.length; i++)
		{
			AddressItem item = createNewAddressItem(children[i].getString(TAG_NAME),
					children[i].getString(TAG_CATEGORY));
			if(item != null)
				addresses.add(item);
		}
	}

public AddressItem createNewAddressItem(String name, String categoryName) {
		AddressCategory category = AddressCategory.getCategoryMap().get(categoryName);
		return new AddressItem(name, category);
		}
}

//显示之前，先加载
public AddressItem[] getAddresses(){
		if(addresses == null)
			loadAddresses();
		return (AddressItem[])addresses.toArray(
				new AddressItem[addresses.size()]);
	}

而数据的保存在Activator的stop方法中，插件退出时保存数据

public void stop(BundleContext context) throws Exception {		
		AddressManager.getManager().saveAddresses();
		plugin = null;		
		super.stop(context);
	}

由于包含中文，要在浏览器或编辑器中正确显示xml文档，需要将xml的编码方式从UTF-8改成gb2312