77 lines
1.8 KiB
Go
77 lines
1.8 KiB
Go
|
// Copyright (c) 2016 Couchbase, Inc.
|
||
|
|
//
|
||
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
||
|
|
// you may not use this file except in compliance with the License.
|
||
|
|
// You may obtain a copy of the License at
|
||
|
|
//
|
||
|
|
// http://www.apache.org/licenses/LICENSE-2.0
|
||
|
|
//
|
||
|
|
// Unless required by applicable law or agreed to in writing, software
|
||
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
||
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
||
|
|
// See the License for the specific language governing permissions and
|
||
|
|
// limitations under the License.
|
||
|
|
|
||
|
|
package character
|
||
|
|
|
||
|
|
import (
|
||
|
|
"unicode/utf8"
|
||
|
|
|
||
|
|
"github.com/blevesearch/bleve/analysis"
|
||
|
|
)
|
||
|
|
|
||
|
|
type IsTokenRune func(r rune) bool
|
||
|
|
|
||
|
|
type CharacterTokenizer struct {
|
||
|
|
isTokenRun IsTokenRune
|
||
|
|
}
|
||
|
|
|
||
|
|
func NewCharacterTokenizer(f IsTokenRune) *CharacterTokenizer {
|
||
|
|
return &CharacterTokenizer{
|
||
|
|
isTokenRun: f,
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
func (c *CharacterTokenizer) Tokenize(input []byte) analysis.TokenStream {
|
||
|
|
|
||
|
|
rv := make(analysis.TokenStream, 0, 1024)
|
||
|
|
|
||
|
|
offset := 0
|
||
|
|
start := 0
|
||
|
|
end := 0
|
||
|
|
count := 0
|
||
|
|
for currRune, size := utf8.DecodeRune(input[offset:]); currRune != utf8.RuneError; currRune, size = utf8.DecodeRune(input[offset:]) {
|
||
|
|
isToken := c.isTokenRun(currRune)
|
||
|
|
if isToken {
|
||
|
|
end = offset + size
|
||
|
|
} else {
|
||
|
|
if end-start > 0 {
|
||
|
|
// build token
|
||
|
|
rv = append(rv, &analysis.Token{
|
||
|
|
Term: input[start:end],
|
||
|
|
Start: start,
|
||
|
|
End: end,
|
||
|
|
Position: count + 1,
|
||
|
|
Type: analysis.AlphaNumeric,
|
||
|
|
})
|
||
|
|
count++
|
||
|
|
}
|
||
|
|
start = offset + size
|
||
|
|
end = start
|
||
|
|
}
|
||
|
|
offset += size
|
||
|
|
}
|
||
|
|
// if we ended in the middle of a token, finish it
|
||
|
|
if end-start > 0 {
|
||
|
|
// build token
|
||
|
|
rv = append(rv, &analysis.Token{
|
||
|
|
Term: input[start:end],
|
||
|
|
Start: start,
|
||
|
|
End: end,
|
||
|
|
Position: count + 1,
|
||
|
|
Type: analysis.AlphaNumeric,
|
||
|
|
})
|
||
|
|
}
|
||
|
|
return rv
|
||
|
|
}
|