rocketmq_common/common/hasher/
string_hasher.rs

1/*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements.  See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License.  You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17pub struct JavaStringHasher;
18
19impl JavaStringHasher {
20    pub fn hash_str(s: &str) -> i32 {
21        let mut state = 0i32;
22        if !s.is_empty() {
23            for c in s.chars() {
24                state = state.wrapping_mul(31).wrapping_add(c as i32);
25            }
26        }
27        state
28    }
29}
30
31#[cfg(test)]
32mod tests {
33    use super::*;
34    #[test]
35    fn hash_str_with_non_empty_string() {
36        let result = JavaStringHasher::hash_str("hello");
37        assert_eq!(result, 99162322);
38    }
39
40    #[test]
41    fn hash_str_with_empty_string() {
42        let result = JavaStringHasher::hash_str("");
43        assert_eq!(result, 0);
44    }
45
46    #[test]
47    fn hash_str_with_special_characters() {
48        let result = JavaStringHasher::hash_str("!@#");
49        assert_eq!(result, 33732);
50    }
51
52    #[test]
53    fn hash_str_with_long_string() {
54        let result = JavaStringHasher::hash_str("a".repeat(1000).as_str());
55        assert_eq!(result, 904019584);
56    }
57}
rocketmq_common/common/hasher/string_hasher.rs

rocketmq_common/common/hasher/
string_hasher.rs
