java - How do I bypass inaccessible files? -

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• what nullpointerexception, , how fix it? 12 answers

i trying find of files named, in directory have chosen. code have works when c:\program files, or c:\users. when c:/ stuck in recycle bin , java.lang.nullpointerexception , stops @ c:\$recycle.bin\s-1-5-21-1478355014-127360780-1969717230-1002144.

public void directoryserch(string target, string dirname){     file f = new file(dirname); system.out.println("h");     if(!f.isdirectory()){         throw new illegalargumentexception("that not valid directory");     }     for(file folderitem : f.listfiles()){         if(folderitem.isdirectory()){             system.out.println(folderitem.getabsolutepath());             if(!folderitem.equals("")){                 directoryserch(target,folderitem.getpath());             }             // return result if not empty             /*  if (!result.equals(folderitem.getname())){             files[filesfounfd] = folderitem.getabsolutepath();             filesfounfd++;             }*/         }else{             if(folderitem.getname().equals(target)){                 files[filesfounfd] = folderitem.getabsolutepath();                 system.out.println(folderitem.getabsolutepath());                 filesfounfd++;             }         }             } } 

what can not issue works in cases when not have deal recycle bin?

 for(file folderitem : f.listfiles()){ 

the problem here. listfiles() can return null, , syntax can throw npe. change to:

 file[] files = f.listfiles();  if (files != null) {     for(file folderitem : files){