java操作xml的问题

我在程序中运行修改xml文件后 在通过程序将刚才修改的xml删除，删除不了 说正在使用 
这是修改xml的代码：
public static boolean docXMl(Document document,String filename){
boolean flag =true;

try {
TransformerFactory tFactory = TransformerFactory.newInstance();
Transformer transformer = tFactory.newTransformer();

DOMSource source = new DOMSource(document);
StreamResult result = new StreamResult(new File(filename));
transformer.transform(source, result);
} catch (Exception e) {
flag = false;
e.printStackTrace();
}
return flag;
}
public static Document load(String filename){
Document document = null;
try {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); 
DocumentBuilder builder = factory.newDocumentBuilder();
document = builder.parse(new File(filename));
document.normalize();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return document;
}

public static void xmlUpdate(){
Document document = load("E://workspace//zcxm//xml//XMLFile.xml");
Element root =  document.getDocumentElement();
//修改节点中的内容
        docXMl(document,"E://workspace//zcxm//xm