java - Return null when file is missing or empty -


i'm using code hdd data linux:

public void gethddinfo() throws ioexception     {         try (directorystream<path> ds = files.newdirectorystream(paths.get("/sys/block"), "sd*"))         {             // hdd model             streamsupport.stream(ds.spliterator(), false)                 .map(p -> p.resolve("device/model")).flatmap(wrap(files::lines))          }         try (directorystream<path> ds = files.newdirectorystream(paths.get("/sys/block"), "sd*"))         {             // hdd vendor             streamsupport.stream(ds.spliterator(), false)                 .map(p -> p.resolve("device/vendor")).flatmap(wrap(files::lines))          }         try (directorystream<path> ds = files.newdirectorystream(paths.get("/sys/block"), "sd*"))         {             // hdd state             streamsupport.stream(ds.spliterator(), false)                 .map(p -> p.resolve("device/state")).flatmap(wrap(files::lines))                 .foreach(system.out::println);         }         try (directorystream<path> ds = files.newdirectorystream(paths.get("/sys/block"), "sd*"))         {             // hdd revision             streamsupport.stream(ds.spliterator(), false)                 .map(p -> p.resolve("device/rev")).flatmap(wrap(files::lines))                 .foreach(system.out::println);         }         try (directorystream<path> ds = files.newdirectorystream(paths.get("/sys/block"), "sd*"))         {             // hdd scsi level             streamsupport.stream(ds.spliterator(), false)                 .map(p -> p.resolve("device/scsi_level")).flatmap(wrap(files::lines))                 .foreach(system.out::println);         }         try (directorystream<path> ds = files.newdirectorystream(paths.get("/sys/block"), "sd*"))         {             // hdd scsi removable             streamsupport.stream(ds.spliterator(), false)                 .map(p -> p.resolve("device/removable")).flatmap(wrap(files::lines))                 .foreach(system.out::println);         }         try (directorystream<path> ds = files.newdirectorystream(paths.get("/sys/block"), "sd*"))         {             // hdd scsi level             streamsupport.stream(ds.spliterator(), false)                 .map(p -> p.resolve("device/size")).flatmap(wrap(files::lines))                 .foreach(system.out::println);         }     }

but not files available or of them empty. exception:

java.nio.file.nosuchfileexception: \sys\block

i there way modify code return null when there no such file or file empty?

this should handle cases files don't exist:

try {   // of stuff } catch (nosuchfileexception ex) {   return null; }

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