java

看看性能!加载15万多个词,搜索不到1毫秒。  不知和ZZL算法比如何

Load dict in 1273 ms, size=157202
Search pattern: 中国
Searched in 1 ms.
Map size=389[,中国,中国上海,中国专利,中国专利局,...]

Search pattern: abc
Searched in 0 ms.
Map size=0[]

Search pattern: 电子
Searched in 0 ms.
Map size=130[,电子,电子世界,电子乐器,电子书,电子书下载,...]

Search pattern: 中
Searched in 0 ms.
Map size=1147[,中上,中上层,中上游,中下,中下层,...]


Java code

public class TreeMapTest {   
    private SortedMap<String,String> words = new TreeMap<String,String>();
   
    public TreeMapTest(String[] args){
        for(String s:args){
            words.put(s, s);
        }
    }
   
    public TreeMapTest(String dict) throws Exception{
        long start = System.currentTimeMillis();
        File in = new File(dict);
        BufferedReader reader = new BufferedReader(new FileReader(in));
        String line = reader.readLine();
        while(null != line){
            String[] ws = line.split("\t");
            words.put(ws[0], ws[0]);
            line = reader.readLine();
        }
        reader.close();
        long end = System.currentTimeMillis();
        System.out.println("Load dict with " + (end-start) + " ms, size=" + words.size());
    }
   
    public void search(String pattern){
        System.out.println("Search pattern: " + pattern);
        long start = System.currentTimeMillis();
        String fromKey = pattern;
        String toKey = null;
        int length = pattern.length();
        if( length == 1){
            toKey = String.valueOf((char)(pattern.charAt(0)+1));
        }else{
            StringBuilder sb = new StringBuilder();
            sb.append(pattern.substring(0, length-1));
            sb.append((char)(pattern.charAt(length-1)+1));
            toKey = sb.toString();
        }       
        SortedMap<String,String> result =  words.subMap(fromKey, toKey);
        long end = System.currentTimeMillis();
        System.out.println("Searched in " + (end-start) + " ms.");
        show(result);
    }
   
    public void show(SortedMap<String,String> map){
        System.out.println("Map size=" + map.size() + "[");
        Set<String> keys = map.keySet();
        for(String key:keys){
            System.out.print(",");
            System.out.print(key);
        }       
        System.out.println("]");
    }

    public static void main(String[] args) throws Exception {
//        String[] strs = {"abc","ab","d","abcde","da","db","dbc","ac","aca","中国","中华人民共和国","中国人","中国龙"};
//        TreeMapTest test = new TreeMapTest(strs);
        TreeMapTest test = new TreeMapTest("your dict file");
       
       
        test.search("中国");
        test.search("abc");
        test.search("电子");
        test.search("中");
    }

}

你可能感兴趣的:(Pattern,search)