Duplicate file finder based on comparing 1st 24 characters of file name - duplicates

Question

I have more than 12000 files and I need to compare 1st 24 characters of each file name.
If match is found than need to delete it.
for e.g
dat_2016_08_13_11_01_02_1339.data
dat_2016_08_13_11_01_02_2140.data
dat_2016_08_13_12_47_33_1362.data
dat_2016_08_13_13_12_03_1062.data
dat_2016_08_13_13_12_03_0217.data
In above case :
File 1 is duplicate of 2 as 1st 24 characters "dat_2016_08_13_11_01_02" are same.
File 4 is duplicate of 5 as 1st 24 characters "dat_2016_08_13_13_12_03" are same.
FYI, date of file creation for file 1&2 is different. so, can't use attribute comparison.
I have gone through various duplicate file finder tools. no one gives the way to customize compare technique for my special need.
Can anyone suggest the way to do it ?

Answer 1

Here is a program i quickly coded see if this helps:
Remember Change the directory
import java.io.File;
public class duplicates {
public static void main(String[] args) throws Exception{
File f=new File("C:/testfolder");//insert your directory here
File[] files=f.listFiles();
for(int y=0;y<files.length;y++){
f=new File("C:/testfolder");
files=f.listFiles();
String find="";
if(files[y].getName().length()>24){
find=files[y].getName().substring(0,24);
}else{
continue;
}
for(int x=0;x<files.length;x++){
if(files[x].getName().startsWith(find)){
System.out.println("deleted file:"+files[x].getAbsolutePath());
files[x].delete();
break;
}
}
}
System.out.println("DONE!!");
}
}
I have not tested this with the large no. of files but it should work(might take a min or 2)
Hope this Helped:)