Added API to get range from fastfield

1 files changed, 22 insertions, 0 deletions

diff --git a/src/fastfield/reader.rs b/src/fastfield/reader.rs
index 7c01d0a..8413527 100644
--- a/src/fastfield/reader.rs
+++ b/src/fastfield/reader.rs
@@ -13,6 +13,7 @@ use common::bitpacker::compute_num_bits;
 use common::bitpacker::BitUnpacker;
 use schema::FieldType;
 use error::ResultExt;
+use std::mem;
 use common;
 use owning_ref::OwningRef;
 
@@ -29,6 +30,7 @@ pub trait FastFieldReader: Sized {
     /// This accessor should return as fast as possible.
     fn get(&self, doc: DocId) -> Self::ValueType;
 
+    fn get_range(&self, start: u32, output: &mut [Self::ValueType]);
 
     /// Opens a fast field given a source.
     fn open(source: ReadOnlySource) -> Self;
@@ -80,6 +82,13 @@ impl FastFieldReader for U64FastFieldReader {
         }
     }
 
+    fn get_range(&self, start: u32, output: &mut [Self::ValueType]) {
+        self.bit_unpacker.get_range(start, output);
+        for out in output.iter_mut() {
+            *out += self.min_value;
+        }
+    }
+
     /// Opens a new fast field reader given a read only source.
     ///
     /// # Panics
@@ -181,6 +190,19 @@ impl FastFieldReader for I64FastFieldReader {
         common::u64_to_i64(self.underlying.get(doc))
     }
 
+    ///
+    /// # Panics
+    ///
+    /// May panic or return wrong random result if `doc`
+    /// is greater or equal to the segment's `maxdoc`.
+    fn get_range(&self, start: u32, output: &mut [Self::ValueType]) {
+        let output_u64: &mut [u64] = unsafe { mem::transmute(output) };
+        self.underlying.get_range(start, output_u64);
+        for mut_val in output_u64.iter_mut() {
+            *mut_val ^= 1 << 63;
+        }
+    }
+
     /// Opens a new fast field reader given a read only source.
     ///
     /// # Panics