Assuming you're using one of the metadata methods in the official Java SDK (like getMetadata) it sounds like you're doing toString and trying to manually parse this, which is unnecessary. This metadata method returns a DbxEntry (which you can convert to DbxEntry.File using asFile. You can then directly access the information you want on that object. E.g.:
DbxEntry.File fileInfo;
try {
fileInfo = dbxClient.getMetadata("/test.txt").asFile();
}
catch (DbxException ex) {
ex.printStackTrace();
System.err.println("Error in getMetadata(): " + ex.getMessage());
System.exit(1); return;
}
System.out.println("fileInfo name: " + fileInfo.name);
System.out.println("fileInfo lastModified: " + fileInfo.lastModified);
System.out.println("fileInfo humanSize: " + fileInfo.humanSize);