String fileName="NoName.txt";

   else if(eventSource==saveItem){
    fileName="NoName.txt";
    writeFile(fileName);
}
   else if(eventSource==saveAsItem){
    fileName=null;
    writeFile(fileName);

public void writeFile(String name){
        File filea ;
        String messagef="文件未找到";
        FileOutputStream outputfile=null;
        if(fileName==null){
            JFileChooser savefile=new JFileChooser();
            savefile.setDialogTitle("保存文件");
            savefile.setApproveButtonText("保存");
            savefile.showSaveDialog(this);
            filea=savefile.getSelectedFile();
            
        if(filea==null)return;
        }
        else {
            filea=new File(fileName);
        }
        try{
            outputfile=new FileOutputStream(filea);
        }
        catch(FileNotFoundException e){
            JOptionPane.showMessageDialog(this, messagef, title, type);
        }
        String filecontent=textArea.getText();
        String messaget="下文件错误";
        try{
            outputfile.write(filecontent.getBytes());
        }
        catch(IOException e){
            JOptionPane.showMessageDialog(this, messaget, title, type);
        }
        String messagee="关闭流发生错误";
        try{
            outputfile.close();
        }
        catch(IOException e){
            JOptionPane.showMessageDialog(this, messagee, title, type);
        }
    }    

String fileName=null;