About multiple threads manipulating a file file handle (file stream in Java)

Approving basic information
public static map<string, string> writebasictomap (Class gcprojcheckupclas,string filedirpath,map<string, Object> map) throws exception{
Document doc = Documenthelper.createdocument ();
Add root node
Element root = Doc.addelement ("Gcdata");
Get class Name
String classname= Strutils.getclassnamebypackage (Gcprojcheckupclas.getname ());
Add child elements
Element gcprojcheckup = root.addelement (className);//lowercase is not required

Add nodes.
Field [] Gcprojcheckupfields = Gcprojcheckupclas.getdeclaredfields ();
for (int i = 0; i < gcprojcheckupfields.length; i++) {
System.out.println (Gcprojcheckupfields[i].getname ());
String key = Gcprojcheckupfields[i].getname ();
Element element = Gcprojcheckup.addelement (key);//tag and attribute naming consistent
Element.settext (Map.get (Key.tolowercase ()) ==null? "": (String) Map.get (Key.tolowercase ()));

}
Special treatment Leadergxunicode_organofleader
Element element = Root.addelement ("Leadergxunicode_organofleader");
Element.addtext (Map.get ("Lgol") ==null? "":(String) map.get ("Lgol"));


Instantiating an output Format object
OutputFormat format = Outputformat.createprettyprint ();
Set Output encoding
Format.setencoding ("UTF-8");
Create a file object to write to
String fileName = Nameutils.getfilename (Map.get ("Unitid") ==null? ": Map.get (" Unitid "). ToString (), Map.get (" Unitname ") ==null?": Map.get ("Unitname"). ToString (), Strutils.getclassnamebypackage (Gcprojcheckupclas.getname ()));
String Finalpath=commonpath.inrootpath+filedirpath + file.separator+ filename+ ". xml";
System.out.println (Finalpath);
File File = new file (Finalpath);
Generate XmlWriter objects, parameters in constructors are file streams and formats that require output
FileOutputStream FileOutputStream = new FileOutputStream (file);
XMLWriter writer = new XMLWriter (fileoutputstream, format);
Start writing, the Write method contains the Document object created above
Writer.write (DOC);
if (writer!=null) writer.close ();
if (fileoutputstream!=null) fileoutputstream.close ();

map<string, string> backmap = new hashmap<string, string> ();
Backmap.put ("filename", filename);
FileInputStream InputStream = new FileInputStream (Finalpath);
String MD5 = Digestutils.md5hex (InputStream);
if (inputstream!=null) {inputstream.close ();};
Backmap.put ("MD5", MD5);
return backmap;
}

About multiple threads manipulating a file file handle (file stream in Java)